Hospital Equipment Service, Maintenance, Repair, Validation and Rental

Combination Sterilisation Machines vs Central CSSD in Australian Healthcare

Disclaimer

This content is provided for information only. The authors make no representation or warranty regarding the accuracy, completeness or currency of the content. No information in this whitepaper should be construed as medical advice. Readers should seek appropriate professional guidance before acting on any information contained in this document. The authors expressly disclaim all liability for any direct or indirect loss or damage arising from the use of or reliance on this information.

Introduction

In healthcare, sterilisation and disinfection of reusable equipment are critical for patient safety. In Australia, recent updates to standards (AS 5369:2023) have reinforced rigorous practices for reprocessing reusable medical devices. Hospitals and care facilities face a choice between using decentralised combination machines at the point of care versus relying on a Central Sterile Services Department (CSSD) for sterilising instruments and managing items like bedpans. This whitepaper examines both approaches, highlighting their differences, advantages, and disadvantages across various settings. We consider operational factors from utilisation rates and maintenance needs to breakdown risks as well as cost implications, distribution of equipment, and water and power usage. All analysis is framed in the context of current Australian standards and infection control guidelines.

Different Needs

Different Needs: Instruments vs Bedpans. It is important to distinguish the requirements for surgical instruments versus bedpans and urinals. Surgical instruments and any devices entering sterile body sites are classified as critical items and must be sterilised typically by steam autoclave before reuse. In contrast, bedpans, urinal bottles, and similar waste collection devices are non-critical items that contact intact skin; they do not need full sterilisation but must be thoroughly cleaned and disinfected after each use. Reusable bedpans are normally processed in washer/disinfector machines that use water and heat to achieve high-level disinfection, reducing microbial contamination to safe levels. Actual sterilisation of bedpans between different patients is only considered in special cases e.g. to eliminate C. difficile spores during an outbreak. This fundamental difference means that healthcare facilities often employ two parallel systems: one for instrument sterilisation usually centrally in CSSD and another for on-ward disinfection of bedpans and waste utensils. The decision to use combination machines locally or centralise all reprocessing involves carefully balancing these distinct needs and regulatory requirements.

Combination Sterilisation or Disinfection Machines

“Combination machines” refer to equipment installed in clinical areas that can perform automated cleaning and disinfection/sterilisation tasks on-site. Common examples include bedpan washer-disinfectors often combined with utensil washers and bench-top steam sterilisers for instruments. For instance, Australian manufacturers offer combination bedpan and utensil washer/disinfectors that can clean bedpans, urinal bottles, kidney dishes and bowls in one unit. By using one machine for multiple functions, wards can save room and budget space that can be redirected to patient care areas, additional beds, theaters, etc.. These combination units are deployed in dirty utility rooms on wards or in small facilities to handle waste management: they automatically empty and rinse waste, wash with detergent, then disinfect with hot water or steam to achieve the required thermal disinfection level e.g. Ao600 as recommended in AS/NZS 4187.

Modern combination washers are built to meet stringent standards. The example above is validated to ISO 15883 (the international standard for washer-disinfectors) and was designed to comply with Australia’s AS/NZS 4187:2014 for reprocessing reusable medical devices. In practice, this means it achieves a high disinfection efficacy e.g. ≥90 °C thermal sanitisation so that “all harmful microbes on the bedpan will be reduced to safe levels.”. Such machines typically have multiple cycle options but ensure even the quick cycles meet a minimum thermal disinfection standard no simple “rinse only” modes that would fall short of guidelines. Many units include hands-free operation such as foot pedals or sensors to reduce staff exposure to contaminants, and safety interlocks to prevent misuse.

In addition to bedpan/utensil processors, small steam sterilisers (autoclaves) can be considered “point-of-use” combination machines when used outside of CSSD. Examples are bench-top autoclaves in dental clinics, day surgeries, or ward procedure rooms. These units combine steam generation, sterilisation, and often drying in one device sized for smaller instrument loads. They enable clinics to sterilise their own instruments on-site as required by standards for any reusable instrument in office-based practice. Many bench-top autoclaves are classified under Class S or Class B (EN 13060), indicating they can sterilise wrapped instruments and hollow items, and they must also adhere to quality assurance protocols e.g. temperature monitoring, cycle validation. Under the new standards, any new steriliser or washer, whether in CSSD or in a ward must be installed and performance-qualified according to accepted norms. This ensures that combination machines in decentralised locations still achieve the same sterilisation/disinfection outcomes as a central facility, provided they are used correctly.

Use Cases in Various Settings

Use Cases in Various Settings: Decentralised reprocessing is employed across different healthcare settings in Australia:

Hospital wards: It is standard for inpatient wards medical, surgical, aged care wards, etc. to have a bedpan/flusher disinfector in the ward’s soiled utility room. This allows immediate safe cleaning of bedpans, urinals, emesis bowls and so on, without having to manually clean them which is strongly discouraged due to infection risk. Some large hospitals have upgraded to combination units that also accommodate items like wash bowls, kidney dishes, and instrument trays, giving wards more flexibility in decontaminating various utensils locally. However, for surgical instruments and critical devices, most hospitals still rely on the central CSSD; wards typically only handle interim disinfection or containment e.g. a contaminated instrument might be rinsed or placed in a ward washer for safety, then sent to CSSD.
Smaller hospitals and day procedure centers: Facilities that do not have a full CSSD may use one or two multi-purpose machines to handle all their reprocessing. For example, a small regional hospital or day surgery center might have a washer-disinfector for cleaning instruments and a compact autoclave for sterilisation on-site. The combination approach can be tailored here e.g. a single device might wash and disinfect instruments, which are then immediately sterilised in a small autoclave. Australian standard AS 5369:2023 expanded its scope to include such office-based and non-hospital facilities that use reusable medical devices, meaning even clinics must meet reprocessing standards. For them, self-contained combination machines are often the only practical solution aside from outsourcing, given they are too small to maintain a full CSSD.
Aged care facilities: Nursing homes and long-term care facilities also face the question of bedpan management and equipment sterilisation for items like wound care instruments or dentures. Many have opted for reusable systems with bedpan washer-disinfectors in their utility rooms, as this avoids the continuous cost and waste of single-use bedpans. Combination bedpan/utensil washers designed for healthcare can be found in aged care, where they help control infection especially gastrointestinal outbreaks by ensuring bedpans and commode buckets are disinfected after each use. If the facility performs podiatry or minor procedures, a small steriliser might be on hand as well. Where on-site sterilisation is not available, items might be sent to a nearby hospital CSSD, but this requires transport and coordination. The new standards encourage even these settings to perform a risk assessment and ensure whatever method they use in-house or external meets infection control requirements.

In summary, combination reprocessing machines are versatile tools that enable immediate, on-site cleaning and/or sterilisation of equipment. They are especially vital for managing human waste utensils such as bedpans or urinals at the point of use, which improves infection control by eliminating the need to carry soiled items through hospital corridors. For instruments, decentralised autoclaves can provide quick turnaround in clinics or specific units, though ensuring consistent standards across many small units can be challenging as discussed later. We will next contrast this with the centralised CSSD model.

Central Sterile Services Department

The Central Sterile Services Department (CSSD) is a dedicated unit within a hospital or serving multiple facilities that is responsible for the decontamination, assembly, sterilisation, and distribution of all reusable medical instruments and sterile supplies. In a centralised model, all used instruments and reprocessable devices from operating theatres, wards, clinics, etc. are transported to the CSSD for cleaning and sterilising, and then returned to clinical areas for reuse. The CSSD is designed and equipped to handle high volumes of devices with strict quality control. Typically, it contains industrial-grade washer-disinfectors for automated cleaning of instruments and trays, high-capacity steam sterilisers (autoclaves), drying cabinets or low-temperature sterilisation systems (for heat-sensitive items), and storage areas for sterile stock. It is staffed by trained sterilisation technicians who specialize in instrument reprocessing and infection control practices.

Centralisation offers a controlled environment purpose-built for reprocessing. Australian standards now detail requirements for the CSSD’s physical layout, separating dirty, clean, and sterile areas, with unidirectional workflow and appropriate ventilation. Instruments are received in a decontamination zone, cleaned and disinfected, then passed through to a clean zone for inspection, packing, and finally sterilisation. This spatial separation and one-way movement of instruments from dirty to sterile greatly reduces cross-contamination risk. Meeting these design requirements can be resource-intensive; AS 5369:2023 notes that facilities may need to allocate more space for sterilisation processes to achieve the required separation and airflow. Many hospitals have invested in upgrading their CSSDs accordingly, recognizing the CSSD as a critical hub for patient safety.

Importantly, the CSSD operates under standardized protocols and monitoring. All equipment must meet relevant standards e.g. EN 285 for large steam sterilisers, ISO 15883 for washers and undergo installation and operational qualification. Water quality for cleaning and steam generation is regularly tested, since poor water can affect sterilisation outcomes. Routine testing is performed on the sterilisation process such as biological indicators, Bowie-Dick air-removal tests, and chemical indicators in packs to ensure every batch achieves sterility assurance. Trained staff maintain documentation for each cycle, traceability of instrument sets, and maintenance records. This professional oversight and compliance are strengths of a central CSSD approach.

Networked and Off-site CSSD Services: In some cases, centralisation extends beyond a single hospital. Groups of hospitals or clinics may pool resources into a shared sterilisation service center. For example, several hospitals in a region might use one large off-site reprocessing facility that handles all their instruments. Studies have shown that such resource pooling can improve overall efficiency and economies of scale in sterilisation. A centralized sterilisation center can achieve better utilisation of equipment and staff, potentially reducing the cost per instrument processed. Indeed, specialized medical sterilization centers have emerged that serve multiple clients and offer high-volume, high-efficiency processing. The trade-off is the need for robust logistics daily instrument transport and inventory management and ensuring that transportation times do not hinder timely availability of sterile instruments. It has been noted that while centralising sterilisation can yield cost savings, one must weigh those savings against additional transport costs and operational complexities introduced by a hub-and-spoke system. This is a key consideration even within one hospital moving instruments to a distant CSSD and back involves time and coordination.

In Australia, full centralisation especially outsourcing to off-site CSSDs is usually seen in large metropolitan areas or specialized surgical centers. Smaller hospitals often maintain their own mini-CSSD on-site for convenience. However, virtually every acute-care hospital will have at least a central sterile stock store or department that supplies sterile consumables and handles high-level disinfection/sterilisation of critical items, even if some low-risk items are processed on the wards. Notably, current Australian guidelines (AS 5369:2023) adopt a risk-based approach: they do not outright mandate that all sterilising must occur in one department, but they require health organisations to assess risks and ensure that wherever reprocessing is done (central or decentralized) it meets the same safety standards. Many infection control experts advocate for centralising as much as possible to maintain consistency and oversight, and some international guidelines state that “sterilization services should be centralized” to ensure best practice and efficiency. In practice, hospitals use a hybrid approach: critical and complex reprocessing is centralised, whereas certain items like bedpans or immediate-use needs are handled in the ward with appropriate machines.

Below, we delve into the advantages and disadvantages of using combination machines at the point of care versus a central CSSD model, covering the full range of considerations including utilisation, maintenance and breakdown impacts, cost factors, distribution of equipment, and resource (water/power) usage.

Advantages of Decentralised Combination Machines

Many healthcare facilities find that decentralising some sterilisation/disinfection tasks to the point of use offers significant benefits. Key advantages of using combination machines on wards or in small facilities include:

Immediate Processing and Faster Turnaround: With on-site machines, used items can be reprocessed immediately after use. This is critical for bedpans and urinals, patients need clean items again without delay. A ward washer-disinfector ensures a soiled bedpan can be safely cleaned and disinfected within minutes, ready for the next use, rather than waiting for a trip to CSSD. Quick turnaround also applies to instruments in clinics, a bench-top autoclave can have a sterilised load ready in, say, 30 minutes, which is invaluable for busy GPs or dentists who would otherwise need large inventories or downtime. Immediate processing reduces the time that biohazardous materials sit around, thereby cutting the risk of environmental contamination. Indeed, infection control guidelines note that any strategy should aim to “eliminate sources of risk” by reducing handling, transport, and processing delays for soiled items. Point-of-use reprocessing achieves this by cleaning devices right at the source without waiting in line behind other departments.
Reduced Infection Transmission Risk During Transport: Decentralised machines located in or near patient care areas minimize the need to carry soiled instruments or waste through corridors to a distant reprocessing area. For example, having a flusher in each ward’s dirty utility room means staff don’t have to haul uncovered bedpans or waste containers across the hospital, a practice which could spread pathogens via spills or aerosols. By processing waste and contaminated items on the ward, exposure of other areas to infectious material is greatly lowered. This containment is especially important for managing infectious outbreaks, isolating the decontamination to one area helps prevent hospital-wide contamination. In fact, some infection control protocols suggest even placing dedicated mini-washers in isolation rooms for highly infectious cases to avoid any transport of the waste.
Convenience and Workflow Efficiency for Staff: Nurses and ward staff have ready access to reprocessing without leaving their unit. Bedpan washers are typically hands-free and automated, which saves staff time compared to manually double-bagging and storing soiled items for pickup. Likewise, a clinic with its own steriliser avoids the logistical steps of packaging instruments for external sterilisation and tracking their return. Staff can integrate instrument processing into their regular workflow e.g. a dental assistant can start an autoclave cycle while finishing documentation, rather than driving to a CSSD. This convenience can improve compliance reusable items are more likely to be properly reprocessed immediately if the means are on hand, whereas if the process is cumbersome sending away, there might be temptation to delay or use disposable alternatives.
Dedicated Capacity per Area: With combination machines distributed across departments, each area has its own sterilisation/disinfection capacity. This can prevent bottlenecks that sometimes occur in a busy CSSD where multiple units compete for priority. For instance, an emergency department with a small steriliser can rapidly turn around certain instruments like eye trays or minor procedure kits without waiting behind the main OR sets in CSSD. This localized capacity is beneficial for departments with unique needs or off-hour requirements. It also acts as a backup if the central service is busy or unavailable e.g. after hours, a ward-based machine can handle urgent one-off needs sometimes called “flash” or immediate-use sterilisation, though standards limit this to essential cases.
Space and Multi-Function Efficiency: Modern combination units are designed to be space-saving and versatile. By cleaning multiple types of items, they eliminate the need for separate devices for each task. For example, a single washer-disinfector unit might accommodate four urine bottles and two bedpans or a mix of bowls and kidney dishes in one cycle. This is particularly useful in facilities with limited utility room space one machine can do the work of two. Saving space can have real value: as one Australian manufacturer notes, using a combination bedpan/utensil washer frees up room and budget for “income producing activities, such as additional beds or operating theatres”. In small clinics, a compact bench-top autoclave can often be installed on a countertop, avoiding the need to build a full sterile processing room. Resource flexibility is another aspect, some ward washers can double as emergency instrument washers to render soiled instruments safe for handling before sending to CSSD, adding to staff options in managing contaminated items.
Tailored Solutions for Small or Remote Facilities: Decentralised machines make it feasible for healthcare providers in remote or small-scale settings to maintain safe reprocessing practices. A rural health clinic or a day surgery center with only a few surgical sets can invest in a compliant bench-top steriliser and a small washer rather than relying on a distant hospital’s CSSD. This autonomy means procedures can be scheduled and performed without dependency on external couriers and timetables. It can also be cost-effective at low volumes, outsourcing sterilisation might carry per-item fees and transport costs, which could exceed the amortised cost of running a small autoclave in-house if instrument turnover is modest.
Reduced Disposable Usage and Environmental Benefits: By reprocessing items on-site, facilities can avoid using disposable single-use items as a fallback. For example, without a bedpan washer, a ward might resort to single-use pulp bedpans and macerator disposal. While convenient, disposables generate a large volume of waste and ongoing expense. A reusable system with a flusher avoids adding over a ton of pulp waste per year to landfills or sewers as one ward’s usage can amount to >1000 kg of pulp annually. It also spares the facility the recurring cost of buying consumable bedpans estimated around $5,000 per ward per year for single-use bedpans. Thus, a properly used combination machine is both greener and cheaper in the long run than reliance on disposables. A significant advantage given budget and sustainability pressures.

In summary, point-of-use combination machines offer speed, safety, and self-sufficiency. They keep infection control tightly managed at the ward level and ensure patient care items are turned around rapidly. These benefits explain why essentially all Australian hospitals install bedpan washers on wards, and why many clinics invest in their own sterilisers. However, decentralisation also comes with challenges that must be managed to ensure equivalent outcomes to a professional CSSD. We explore those next.

Disadvantages of Decentralised Combination Machines

Despite their benefits, using numerous small sterilisation/disinfection units across a facility has some downsides. Key disadvantages and challenges of the decentralised approach include:

Higher Maintenance and Oversight Burden: Maintaining many machines in multiple locations can strain technical and quality oversight resources. Each washer or steriliser requires regular maintenance, calibration, and testing to ensure it performs effectively. For example, washer-disinfectors have filters, spray arms and heating elements that need periodic servicing; steam sterilisers need boiler checks, gasket replacements, and performance qualification tests. Managing this across many units means more frequent service visits and increased risk that one or another machine falls out of spec if not monitored. Additionally, ward staff must perform routine care like cleaning chamber strainers or refilling chemicals, and if this is neglected, performance suffers. Studies have found that equipment design and human factors issues can compromise performance of ward-based decontaminators. In one in-use evaluation, bedpan washers had failure rates ranging from ~8% up to 33% in effectively cleaning items, until interventions like adding rinse agents and staff retraining improved outcomes. This highlights that consistent outcomes depend on diligent maintenance and correct use, which can be harder to guarantee when devices are spread out rather than centralized under one expert team.
Variable Staff Training and Compliance: Unlike CSSD where dedicated technicians handle reprocessing, decentralised machines are often operated by general healthcare staff (nurses, aides, dental assistants) as part of their duties. These staff may not have the same level of sterilisation-specific training. Ensuring all users are properly trained on loading, cycle selection, and troubleshooting is an ongoing challenge. Turnover or rotation of ward staff can mean new users who are unfamiliar with the machine’s protocols. Any mistakes, such as overloading a washer, choosing the wrong cycle, or not using required chemical additives could result in suboptimal disinfection. The new standards require annual training in infection control for relevant staff, reflecting the need to keep competencies up to date. But practically, maintaining uniform compliance across many decentralised points is harder than in one CSSD. There is also less direct supervision; for instance, a nurse might remove items from a ward autoclave without the rigorous checks (printout review, indicator validation) that a CSSD tech would perform. This variability can introduce risk of improperly processed items going back into use if a robust audit system isn’t in place. In short, decentralisation demands excellent training and auditing programs to match the reliability of a central department.
Inconsistent Utilisation and Efficiency: A single large CSSD can optimise loads and run machines near capacity, but many small units tend to run partially filled loads, which is less efficient. Some wards might use their washer heavily, while another ward’s machine sits idle most of the day. Under-utilisation means the hospital has paid for capacity that isn’t fully used (wasted capital), and running half-empty cycles wastes water and energy. Conversely, if a ward’s needs temporarily exceed its machine’s capacity, staff might face delays or resort to manual interim measures. Balancing utilisation is tricky when capacity is siloed by location. One machine can’t easily help another if, say, one ward is extremely busy and the next ward’s machine is free. This lack of pooling can be inefficient compared to a central pool of sterilisers. From a cost perspective, duplicate equipment in every unit can be a form of redundancy that doesn’t pay off unless each unit consistently has a high volume of items to process. Hospitals must weigh whether the convenience outweighs the cost of potentially idle time on machines. In some cases, a machine might only process a few instruments a day far below its capacity, raising the question of cost-effectiveness versus sending those few items to CSSD.
Capital and Infrastructure Costs: While a single combination machine is cheaper than building a full CSSD, outfitting every ward or department with its own machines can actually lead to significant aggregate cost. Each unit (washer or autoclave) has a purchase price, installation cost (plumbing, electrical, possibly ventilation for steam), and requires space in the department. For instance, a modern bedpan washer-disinfector requires a 415 V power supply and plumbing for hot water and drainage. If ten wards each have one, that’s ten installations and ten heavy-duty electrical connections. The total capital outlay can approach or even exceed that of a single centralized setup, particularly when including maintenance over the lifespan. Smaller autoclaves also need pure water (distilled or RO water) and may need environmental controls (air conditioning in the room to handle heat and humidity). Additionally, to meet AS 5369:2023 environmental requirements, each area doing reprocessing should ideally have the defined separation of dirty and clean zones, proper flooring, sinks, ventilation, etc.. Retrofitting multiple wards to create mini-sterilisation areas can be impractical. Many older facilities simply lack the physical layout to support compliant reprocessing in every ward which was a pain point as they worked to meet AS/NZS 4187 standards by the end of 2021. The new standard (AS 5369) uses a risk-based approach rather than fixed deadlines, giving some leeway, but the expectation is still that all reprocessing areas meet high standards. This can drive up costs for decentralised approaches if each location must be upgraded to include, for example, a dedicated hand-wash sink, air extraction, or additional storage for sterile goods.
Reliance on Ward Staff and Risk of Human Error: Decentralised reprocessing means ward staff juggle this along with direct patient care duties. During busy times, there is a risk that reprocessing tasks get rushed or deferred e.g. a bedpan might be left sitting if the nurse is attending an emergency, or an instrument might not be sterilised until end of day. Any delays in processing soiled items can increase the risk of organic material drying on instruments making them harder to clean or pathogens proliferating on used devices. Furthermore, human error such as forgetting to start a cycle or misloading a machine can occur when staff are multitasking. In a CSSD, staff focus solely on that job and follow checklists meticulously; on the wards, other priorities compete for attention. Thus, quality assurance is inherently more variable in decentralised models unless significant effort is put into oversight. Health facilities often mitigate this by having infection control or CSSD personnel do regular audits of ward reprocessing practices. Still, the distributed nature means a higher chance that one machine or area “slips through the cracks” in compliance.
Downtime and Redundancy Issues: If a machine in the CSSD breaks down, there are usually multiple other machines to take over, or nearby hospitals/companies that can assist in an emergency. Many large hospitals have 3 to 5 steam sterilisers, for example. In contrast, if a ward’s only combination machine breaks, that ward has no local backup. A broken bedpan washer means that the unit must immediately revert to bedpan disposal bags or carry soiled items elsewhere, which is precisely when infection risks and staff workload spike. A failed small autoclave in a clinic could halt procedures for days while waiting for repair, unless they have a spare or can rush items to another facility. Thus, decentralisation can create single points of failure at each location. Each ward might need a contingency plan such as access to a spare machine or a protocol to borrow another ward’s washer, which isn’t always simple if distances are great or if the other ward’s machine is busy. In summary, equipment breakdowns in a decentralised model can be more disruptive on a local level, even if they don’t paralyse the whole facility as a CSSD outage might. Ensuring rapid technical support for many small units can also be challenging. The biomedical engineering department might prefer focusing on a few big autoclaves rather than chasing many scattered issues.
Energy and Water Consumption: Combination machines at point-of-use can be less efficient per item processed compared to large central equipment. Each ward washer/disinfector has to heat water to high temperatures for each cycle, using electricity, and consume several liters of water for washing and rinsing. These smaller machines might not have the advanced water-recycling or heat-recovery systems that big CSSD equipment can employ. In fact, it’s noted that bedpan washer-disinfectors generally consume more electricity (energy for heating, pumping, etc.) per use than a macerator system, the trade-off being that macerators consume more disposable supplies instead. A 2011 analysis highlighted that while washer-disinfectors have higher energy costs, macerators incur high ongoing costs for single-use bedpans and still require cleaning of supporting parts. Thus, the facility pays either in utilities or in supplies. From a holistic view, multiple decentralised washers mean multiple heaters running, potentially at suboptimal loads, which could collectively use more total water and power than a centralised operation running full loads. Likewise, many small autoclaves might vent steam and heat into each room, possibly straining air conditioning and using water inefficiently. By contrast, a large CSSD steriliser can often process a greater mass of instruments per cycle, spreading the energy cost over more items. Modern CSSD autoclaves also have features like water recirculation and vacuum pumps that drastically cut water usage. Some new models advertise up to 50% water savings with eco-upgrades. In older facilities, each steam steriliser could waste hundreds of liters of cooling water per cycle if not retrofitted. Multiply that by many small units and the waste is significant. An EPA fact sheet once noted a single steriliser running continuously could use ~5,700 L per day if not managed. While bench-top sterilisers use less water overall, they still require frequent water changes and often vent warm moisture into the room. In sum, resource consumption is a concern: decentralisation offers convenience at the cost of potentially duplicated energy expenditure. Hospitals must account for the cumulative impact on water and power bills and consider investing in efficient models or running devices only when needed avoiding standby energy drain. Notably, a life-cycle footprint study found that idle or standby time of sterilisers can consume nearly as much energy as active use if left on continuously, training staff to turn off or idle machines when not in use can mitigate this. On a positive note, technology improvements are reaching even smaller machines: newer autoclaves boast faster cycles that use less power and water, improving their sustainability profile.

In weighing these disadvantages, it becomes clear that decentralised reprocessing demands robust management. A facility choosing this route should have strong policies for training, preventive maintenance schedules for each unit, and possibly central oversight e.g. the CSSD manager or infection control practitioner monitors all ward equipment performance. The risk-based approach of AS 5369:2023 supports this: facilities are expected to perform risk assessments for all reprocessing activities and ensure equivalent patient safety outcomes whether done in one CSSD or at dispersed locations. If an organisation finds that it cannot maintain those standards in every ward due to costs or practical limitations, it may then decide to centralise more of the function. We turn next to the advantages and drawbacks of that centralised model.

Advantages of Centralised CSSD

Centralising sterilisation and disinfection services in a single department or facility offers several key advantages, particularly for medium to large healthcare organisations:

Consistency and High Quality Control: A central CSSD allows for standardised processes under expert supervision. Technicians in CSSD are typically certified in sterilisation techniques and follow strict protocols for every instrument set. This yields highly consistent results every instrument is cleaned, packed, and sterilised following the same criteria and using validated equipment. The CSSD environment is engineered for sterility assurance with proper HVAC, HEPA filtration, etc., which further enhances reliability. Having all reprocessing under one roof means that quality control measures e.g. spore tests, cycle printout reviews, load recalls if a failure occurs can be implemented uniformly for all items. It is easier to maintain compliance with national standards when a dedicated team is responsible: for example, water quality monitoring, calibration of machines, and staff competencies can all be centrally managed. In contrast to decentralised sites where some variability is inevitable, CSSD centralisation fosters a “culture of quality” focused on sterilisation. This specialization is linked to improved patient safety outcomes.
Economies of Scale and Efficiency: Processing reusable devices in one location enables economies of scale. High-throughput washers and large autoclaves can handle big loads, reducing the labor and energy per instrument. For instance, a single 600 L hospital autoclave can sterilise hundreds of instruments or multiple large sets in one cycle, something dozens of small autoclaves would have to run multiple cycles to achieve. This efficiency translates to lower cost per item reprocessed when volume is high. Studies using operations research models have shown that consolidating sterilisation can significantly cut costs, primarily through better resource utilisation and reduced duplication. Instead of each ward buying a washer, the hospital buys a few high-capacity ones for CSSD that are used to near full capacity throughout the day. Additionally, tasks like instrument assembly and packaging benefit from specialization. Staff become very efficient at these tasks, increasing throughput. In economic terms, centralisation avoids the “wasteful redundancy” of under-used assets and concentrates investments where they have maximum utilization. The result is often that the total operating cost is lower for a central service relative to decentralised given sufficient volume to justify the central facility. Even manpower can be optimized: fewer total staff may be needed when they are all working in one department at high productivity, versus nurses across many wards each spending some time on sterilisation. In one analysis of CSSD operations, about 43% of the cost was manpower and 22% utilities, implying that controlling these through efficient staffing and use of machines is key to cost management. A well-run CSSD can leverage these economies to support the entire hospital’s needs economically.
Specialised Equipment for All Needs: A central department can justify purchasing advanced equipment that individual wards could not. This includes not only large steam sterilisers and washers, but other modalities like low-temperature hydrogen peroxide plasma sterilisers for delicate instruments, ultrasonic cleaners for fine debris removal, cart washers for bulky items, and sophisticated packaging systems. By centralising, the hospital ensures that even complex or specialized instruments e.g. flexible endoscopes, robotic surgery instruments are handled with appropriate technology by skilled staff. Wards generally cannot house this variety of equipment. Thus, CSSD centralisation means no compromise on the method. Every item is reprocessed with the optimal technique (steam, low-temp, high-level disinfection, etc.) available in the central arsenal. It also enables bulk processing: for example, a CSSD can wash all surgical instruments in batch washers, which is both labour-saving and produces a uniformly clean result prior to sterilisation.
Greater Redundancy and Reliability: Centralisation often entails having multiple machines of each type, providing inherent backup. Most CSSDs in mid-to-large hospitals have at least two or three autoclaves and multiple washer-disinfectors. If one unit goes down for maintenance or repair, the others can carry the load in the interim. This built-in redundancy ensures that sterilisation operations are rarely interrupted entirely, which is vital for continuous hospital function. Additionally, central CSSD staff typically perform routine preventive maintenance or have service contracts to keep equipment running smoothly. They may also keep emergency backup options like flash sterilisation or loaner machines ready if something fails. In contrast to a ward where a single machine outage causes immediate issues locally, the CSSD can absorb equipment failures with minimal impact on surgical schedules assuming capacity planning and some surplus are in place. Also, since all reprocessing is central, the response to any quality issue is swift and contained e.g. if a steriliser shows a fault, CSSD can quarantine all items from that load and re-run them in another machine. This systematic handling reduces the risk of an unsterile item slipping through, which might be harder to catch in a fragmented system.
Simplified Regulatory Compliance and Documentation: Meeting the detailed documentation requirements of modern standards like tracking each instrument’s reprocessing cycle, recording lot numbers of sterilisation indicators, etc. is easier when done through one integrated system. CSSDs often use tracking software that scans instrument sets, links them to steriliser cycle data, and even logs operator names and times. This would be cumbersome to replicate in every ward with standalone machines. From an accreditation standpoint, surveyors can review the CSSD’s records and be confident that a single system covers the whole hospital’s critical devices. With decentralisation, one would have to compile logs from many machines and ensure uniform record-keeping practices everywhere. The new AS 5369:2023 standard emphasizes things like traceability and risk management in reprocessing. A central CSSD is naturally suited to fulfill these because it operates as a cohesive unit. Moreover, central CSSD managers stay up to date with standards and guidelines, ensuring the hospital’s practices adapt to changes such as new sterilisation monitoring requirements or packaging standards. In a way, centralisation insulates the clinical staff from regulatory complexities. They simply send items to CSSD and receive them back sterilised, while CSSD handles the compliance burden.
Cost Savings in Consumables and Utilities: While running a CSSD has significant costs, it can be more cost-efficient in terms of consumable usage. Bulk purchasing of cleaning chemistries, sterilisation wraps, indicators, etc., often yields discounts. Also, a central department can standardize consumables one type of high-quality wrap for all sets, for instance rather than each ward buying small lots of various products. In terms of utilities, a large steriliser may use a lot of water and power in absolute terms, but if it processes 10 times the load of a small autoclave, the per-instrument resource use can be lower. As mentioned earlier, flushers vs. macerators illustrate this principle: one study model found that even though the flusher-disinfectors had higher upfront and energy costs, the annual operating cost was 6 to 8 times less than a macerator system when considering the full hospital usage. Similarly, one can argue that one central big steriliser’s usage is likely more economical than ten half-used small ones in different wards. Additionally, CSSD can invest in water-saving devices like condensate return systems or load-sensing cycles)that would be impractical for many small units. Effective centralisation thus has the potential to reduce the total cost of sterilisation per procedure, which is increasingly important as hospitals seek efficiency. Research has confirmed that consolidating sterilisation services can yield “significant cost savings… attributed primarily to improved resource utilization and economies of scale.”
Supports High-Volume and Specialized Clinical Services: Central CSSDs are a backbone for surgical departments, without a capable CSSD, an operating theatre simply cannot run multiple cases per day safely. By centralising, hospitals ensure that their most instrument-intensive areas (ORs, catheter labs, delivery suites) have a continuous supply of properly processed tools. CSSD staff coordinate closely with the surgical schedule, often preparing case carts with instrument sets for each surgery. This level of support and integration is only possible with a central model; trying to decentralise such support would be chaotic. Imagine each OR nurse running off to sterilise sets between cases, not feasible. Moreover, any new surgical or diagnostic equipment that needs reprocessing can be accommodated by expanding CSSD capabilities, rather than burdening a clinical ward with figuring out how to clean it. The flexibility and scalability of a central CSSD is a major advantage, it can scale up with new machines or extra shifts if procedure volumes grow, without requiring changes in every user department. This makes it a future-proof investment in many respects.

Overall, a well-run central CSSD provides robust, efficient, and expert-driven sterilisation services that underpin the entire healthcare facility. It excels in standardisation, throughput, and compliance, crucial factors for patient safety and operational effectiveness. However, centralisation is not without drawbacks, particularly regarding logistics and single-point vulnerability, as discussed next.

Disadvantages of Centralised CSSD

While the central CSSD model is considered best practice for many scenarios, it also has potential disadvantages and limitations that organisations must consider:

Transportation Delays and Turnaround Time: Centralising means that used items must travel from the point of use to the CSSD and back after reprocessing. This inherently introduces delays. For surgical instruments, a well-managed system can often return sets for next-day use, but immediate re-use is typically impossible without duplicate inventory. Wards and clinics must have enough spare instruments or bedpans to last until items come back sterile, which increases inventory costs. If an unexpected need arises (say an extra surgical case or a one-off instrument needed urgently), relying solely on CSSD might not meet the time frame, this is why some ORs keep a small flash steriliser for emergencies. For ward items like commode pans or shower chairs that might need disinfection, sending them to CSSD could take hours or more; hence these are usually handled on the ward out of necessity. Overall, the turnaround time in a centralized system is slower compared to on-demand local cleaning. In fast-paced environments or those requiring frequent reuse of items, this can be a significant drawback. It can also impact patient flow: for example, if a clinic has only a limited number of ENT scopes and they all had to go to CSSD, the clinic might need to space out appointments to wait for their return, unless they buy more scopes. Proper planning and sufficient inventory can mitigate this, but at the cost of tying up more capital in extra instruments.
Complex Logistics and Handling: A central CSSD introduces a logistical operation within the hospital. There needs to be a system for collecting soiled items from all over the facility, often involving dedicated trolleys, elevators, and staff who pick up at scheduled times. After processing, sterile items must be packaged, labelled, and delivered or made available for pickup by each user department. This complexity can lead to errors like items sent to the wrong department, missing instruments, or damage during transport if not carefully managed. Each handoff from OR to soiled bin, bin to CSSD decontamination, CSSD to sterile store, store to ward is a point where something could be misplaced or contaminated if protocol isn’t followed. For instance, if a container isn’t properly closed, instruments could be exposed during transit. Additionally, CSSD must track hundreds of instrument sets and ensure they all get back to their proper location, a task often aided by barcoding systems. The coordination effort is significant, somewhat akin to running an internal supply chain. Smaller facilities might find this overhead burdensome compared to just cleaning something on the spot. For multi-site centralisation like an off-site CSSD serving several hospitals, the logistics extend to trucks, traffic delays, and even greater distances, amplifying these issues. Any breakdown in the chain, e.g. a lift out of service or a delivery driver calling in sick can disrupt the timely availability of sterile supplies.
Single Point of Failure Risk: Having one central department means the entire facility is dependent on its proper functioning. If the CSSD encounters a serious problem, it can jeopardize hospital operations. For example, if a steriliser malfunctions and there is no backup, surgeries might have to be postponed. If a water main break or power outage hits the CSSD area, the sterilisation processes could halt. Even events like a fire alarm, flood, or contamination incident e.g. a fungal spore outbreak in the CSSD environment could force a temporary shutdown of the department. This centralisation of risk is often managed by contingency plans: hospitals maintain service contracts for emergency repairs, have generators for CSSD, or arrange for neighboring hospitals to assist in a crisis. But nonetheless, the dependency is there that the CSSD is a “critical node”. In contrast, a decentralised system spreads out the risk; a failure in one ward’s reprocessor doesn’t directly stop another ward or the OR. It’s worth noting that CSSDs do typically have redundancy with multiple machines as discussed, so the most likely failures are mitigated. However, major incidents like building issues or widespread staff illness can indeed bring the service down. This is why risk mitigation strategies are crucial, some hospitals maintain a small reserve of critical instruments sterilised and ready in case of CSSD disruption, and as mentioned, quick access to external sterilisation resources can be life-saving in extreme cases. The new risk-based standards explicitly encourage facilities to consider such scenarios in their planning.
High Initial Capital and Space Requirements: Building or upgrading a CSSD is capital-intensive. It requires costly equipment each large autoclave, washer, or scope reprocessor can cost tens to hundreds of thousands of dollars. Beyond equipment, the department must have specialized HVAC systems, purified water supply (RO or deionizer units), boilers or steam generators, sterilisation packaging areas, and proper construction (sealed floors, stainless steel benches, etc.). The physical space needed is significant: AS 5369:2023 even underscores that facilities may need to devote more floor area to sterilisation processes than in the past. For older or smaller hospitals, carving out this space is a challenge; it might mean repurposing clinical areas or building extensions. The cost and complexity can be a barrier, especially in rural or low-resource settings. In comparison, decentralised solutions might be implemented incrementally (one autoclave here, one washer there) without a huge one-time project. From a budgeting perspective, it can be easier to acquire a few $10k machines for departments over time than to secure a lump sum of millions for a full CSSD renovation. This is one reason some smaller hospitals historically under-invested in CSSDs, instead doing a minimum or sending instruments to larger facilities. However, the pressure of modern standards like AS/NZS 4187’s requirements which had an initial compliance deadline of 2021 has pushed many to invest in central upgrades despite the cost. Some have turned to external outsourcing, having an off-site company build/operate a CSSD to alleviate their need to invest capital, but that introduces other dependencies. In summary, the barrier to entry for a top-notch CSSD is high, which can be a disadvantage for facilities on tight budgets.
Operational Costs: Staffing and Utilities: Running a CSSD is an ongoing expense. It requires dedicated full-time staff across multiple shifts, often 7-day, 24-hour coverage in larger hospitals. Skilled sterilisation technicians must be hired and retained; labor often forms the largest part of CSSD operating cost (around 43% of CSSD cost in one study). In a decentralised scenario, while you still need staff time to do the work, it might be absorbed into existing roles though that has its own issues of quality as noted. With centralisation, the hospital explicitly runs a department with its own management, training, certification, etc., which smaller facilities might find hard to justify if their instrument volume is low. Additionally, CSSD equipment consumes significant water, electricity, and consumables (detergents, wraps, etc.). Utilities comprised about 22% of CSSD costs in one analysis. If a hospital’s reprocessing needs are modest, these costs might not scale down proportionally, you still need at least one steriliser, one washer, etc., running even at partial load. Thus for smaller operations, a central CSSD can be inefficient if underutilised, making the per-item cost quite high. They might find themselves paying for idle capacity during afternoons or weekends when surgery is light. This is where a distributed or on-demand model could theoretically be cheaper if, for example, a ward steriliser is only run when needed. Each facility has to do a cost analysis: below a certain volume threshold, it might be more economical to share a CSSD or decentralise rather than maintain a fully staffed central one.
Less Flexibility for Unplanned Needs: In a completely central model, when a department needs something sterile at short notice, they are dependent on CSSD’s schedule. If an instrument is dropped during a procedure, a replacement must be available or the case waits immediate reprocessing in CSSD might not be feasible due to transit and heating times. This can affect clinical flexibility. Decentralised backups like an OR flash steriliser or a ward’s own small autoclave are often implemented to counter this disadvantage. Essentially, the central model can be somewhat inflexible for ad-hoc or emergency reprocessing unless it has built-in rapid-cycle machines. Some CSSDs have an “IUSS” (immediate use steam steriliser) capability on site near the OR for this reason. But if not, the system might not cope well with last-minute requests, for example, a surgeon wanting to add a case with instruments that are currently dirty, if CSSD is heavily scheduled, this could pose a delay.
Bedpans and Bulky Items Logistics: While instruments can be centrally handled, items like bedpans, commode chairs, and patient care equipment are logistically very difficult to centralise. The central CSSD model doesn’t practically extend to daily patient waste containers due to the rapid turnover needed and the infection hazard of transporting fecal matter across the hospital. Therefore, even a highly centralised hospital will still need to manage these non-critical but high-soil items locally. This means a central CSSD does not entirely eliminate the need for ward-level decontamination equipment, you wouldn’t send a used bedpan through the hospital to CSSD because of spill risks and odor issues. As a result, central CSSD has a blind spot for such items, and a hybrid approach remains necessary. In essence, centralisation is mainly a solution for surgical/medical devices; it’s not a one-size-fits-all for every item. This isn’t so much a disadvantage as a limitation, but it underscores that combination machines like bedpan flushers will remain in use even in hospitals with strong CSSDs.

In evaluating these disadvantages, one should remember that many can be mitigated with proper planning. Hospitals often maintain a mix of central and local solutions to get the best of both worlds, for example, centralising instrument sterilisation but keeping bedpan washers on the wards, or using an off-site CSSD for routine instrument loads but retaining a small on-site unit for emergency needs. The Australian guidelines now encourage a risk-managed approach: facilities should identify where centralisation is critical and where decentralised solutions are acceptable or required, rather than an all-or-nothing stance. Next, we discuss resource consumption in more detail and the impact of updated standards on these practices.

Resource Usage: Water and Power Considerations

Sterilisation and disinfection processes can be resource-intensive. A thorough comparison between combination machines and central CSSD must include their water and energy footprints, as these affect both cost and environmental sustainability.

Water Usage: Both ward-based washers and central CSSD equipment consume water for washing and for steam generation. Bedpan washer-disinfectors use water to rinse waste and to produce the hot water/steam for disinfection at ≥90 °C. Per cycle, a bedpan washer might use several liters of water (exact amounts vary by model and cycle length). Over a day, an active ward’s flusher could consume tens to hundreds of liters. Across a hospital with many such units, this adds up. On the other hand, pulp macerators use water to flush the pulp slurry into the sewer, and though each cycle is shorter, the cumulative water use isn’t negligible either. One advantage of reusables noted in studies is that, despite using water and power, the overall cost and environmental load was lower than disposable flushers’ operational costs are many times less than the ongoing manufacture and disposal of pulp products. In CSSD, large washers typically have multiple fill-and-drain cycles (wash, several rinses, thermal rinse) and can use on the order of 40 to 50 L per load for a big cart washer. Steam sterilisers require water to generate steam and often for cooling and air removal. Traditional hospital sterilisers with water ejector vacuum pumps can use huge volumes of cooling water if not reclaimed. For example, a study at Stanford University noted that a single old-model steriliser could use about ~5,700 L of water per day just in the vacuum ejector cooling the steam to the drain. Modern sterilisers mitigate this by using water recirculation or switching to electric vacuum pumps, reducing water waste by 80 to 90%. Some newer large sterilisers advertise “water-saving” modes that cut water use by half or more. Bench-top autoclaves usually don’t use continuous cooling water, they vent steam into a reservoir or condenser ,so their water use is more directly proportional to the steam needed for the chamber e.g. a 20 L autoclave might use a few liters of distilled water per cycle. Thus, per cycle, large CSSD sterilisers might use more water, but they also process more instruments. One study quantified that a hospital sterilisation suite used about 58 L of water per 1 kg of instruments sterilised accounting for all washing and sterilising steps. If many small autoclaves ran inefficiently, that figure could potentially be higher. From an environmental perspective, central CSSDs can invest in water treatment (recycling rinse water, etc.) which is harder to implement on distributed machines. Hospitals concerned with water conservation often retrofit autoclaves with devices to shut off water when idle since older ones ran water continuously to cool effluent. Training staff to turn off ward machines when not in use similarly prevents waste. In water-scarce regions, these factors might influence the choice of technology, for instance, favoring efficient washers over macerators if sewage load or water supply is problematic.

Energy (Power) Usage: Electricity consumption is significant for any high-temperature decontamination. Ward combination machines (flushers) typically heat water electrically to produce thermal disinfection, and have motors/pumps, requiring a heavy power circuit. Autoclaves have heating elements to generate steam (or use building steam, which still comes from a boiler using energy). A bedpan washer might be rated at several kilowatts and draw that for each cycle’s heating phase. If run frequently, this can be a notable load. It’s observed that “bedpan washers cost more in terms of energy consumption (electricity)” compared to macerators, because macerators use mechanical shredding and cold water flush (less energy per cycle, though more waste generation). In a central CSSD, energy is used by washers (hot water heating), sterilisers (steam heat, vacuum pumps), dryers, and HVAC (to maintain proper ventilation and cooling in the department). A study of one hospital’s sterilisation suite found that standby energy was a surprisingly large component. Machines idling but kept hot consumed over 21,000 kWh in a year, about 40% of the total sterilisation energy usage. This implies there’s room to save by shutting off equipment when not needed, whether central or local. Another metric from that study was about 1.9 kWh of electricity per kg of instruments sterilised on average. Newer sterilisers with faster cycles can reduce energy per load by completing the task quicker (less heating time). When comparing decentral vs central, one must consider scale: ten small autoclaves each with a 2 kW heater might collectively draw more power than one big autoclave with a 6 kW heater handling the same total load. Thus, centralisation can be more energy-efficient for high volumes due to less duplicate heating of multiple chambers. On the flip side, if the volume is low, a big steriliser might run half-empty, effectively wasting some energy heating unused capacity. Therefore, utilisation is key to energy efficiency: a fully loaded smaller machine could be more efficient than a half-full large one, and vice versa. Many hospitals are adopting sustainability initiatives to optimise these processes, whether by investing in energy-efficient machines or simply better production planning to maximise each cycle’s load.

Detergents and Consumables: Both systems use chemical products, detergents in washers, enzymes for some cleaning, and packaging materials for sterilisation. Central CSSD likely uses more sterile wrap, indicator strips, and protective packaging because every instrument set is wrapped for sterility after processing. Decentralised instrument sterilisation like in clinics often uses disposable pouches or small wraps as well, so per item it might be similar or even higher since small loads still need packaging. Washer-disinfectors require detergent and possibly rinse aid dosing; these are typically centralized purchases but ward machines will need their own supply cartridges. Having many machines might mean multiple stock points for chemicals, increasing complexity a bit. Environmentally, the impact of chemicals is roughly proportional to the number of cycles run, centralisation could reduce this if it lowers total cycles through better load consolidation. For bedpan cleaning, using reusables avoids the consumable bedpan but uses detergent and hot water instead. It’s often regarded as a net positive environmentally if waste management and water treatment are functioning, but local factors like the carbon intensity of electricity or the waste handling system can tilt the calculation. An Australian consideration is that effluent regulations might restrict macerator use in some areas due to load on sewage treatment, implicitly favoring thermal disinfection with its higher energy use over generating more solid waste effluent.

In conclusion on resources, central CSSD vs decentralised machines is a trade-off between concentrated and distributed resource consumption. A centralized CSSD can optimize and even invest in greener technology at one site for instance, upgrading to water-efficient sterilisers or installing solar panels to offset electricity. Decentralised machines offer little incremental benefit to the environment unless they prevent the use of disposables which they do for bedpans. The whitepaper’s analysis suggests that, from a cost perspective, water and power usage is a significant part of operating costs in either model, around one-fifth to one-quarter of CSSD costs were utilities. Healthcare facilities in Australia are increasingly mindful of these factors, aiming to comply not just with infection control standards but also with sustainability goals. It’s worth noting that sterilisation by steam is still considered more environmentally friendly than many alternatives like single-use devices or chemical high-level disinfection because it uses only water and energy and can be efficient. The key is to manage it wisely, whether through central or distributed means.

Impact of Recent Australian Standards and Guidelines

The landscape of sterilisation and disinfection in Australia has been shaped by evolving standards, notably the transition from AS/NZS 4187:2014 to AS 5369:2023. These standards set the benchmark for how reusable medical devices should be reprocessed in health service organizations. The recent changes influence decisions around combination machines vs CSSD in several ways:

Expanded Scope and Applicability: AS 5369:2023 explicitly covers not only hospitals but also office-based practices and other facilities that reprocess reusable devices. This means small clinics (GP offices, podiatry, etc.) are expected to follow essentially the same principles as big hospitals. The practical implication is that decentralised sterilisation in those settings must meet high standards, every bench-top autoclave or manual cleaning station in a clinic should comply with the same quality requirements e.g. validation, routine monitoring as a hospital CSSD. This levels the playing field and pushes even solo practitioners to consider whether they can maintain compliance in-house or if they should outsource or switch to single-use devices. In aged care, it similarly brings them under the umbrella fully. In making decisions, facilities must recognize there is no “easy exemption” for being small, the standard demands patient safety regardless of setting. However, AS 5369 uses a risk-based approach and notably does not set a hard compliance deadline, unlike the previous AS/NZS 4187 which had target dates. This means facilities have flexibility to implement improvements gradually, prioritising according to risk. For example, a small clinic might determine via risk assessment that their volume of critical devices is low and manage the risk with a high-quality bench-top steriliser plus strict procedures, rather than immediately building a CSSD. Conversely, a hospital might identify a risk in ward-based reprocessing and plan to centralise it over a few years. The absence of a fixed timeframe removes some pressure but places responsibility on facilities to proactively manage their compliance plans.

Equipment and Process Validation: The standards require that all cleaning, disinfecting, and sterilising equipment whether a huge autoclave or a small washer meets relevant ISO/EN standards and is subject to validation (IQ, OQ, PQ). This means that any combination machine used must have documented efficacy. For hospital administrators, this might favor known medical device manufacturers and discourage ad-hoc or non-validated solutions. For instance, a custom-built steriliser or using non-medical dishwashers for instruments would not be acceptable. The standard also insists on performance qualification after installation and regularly, so every decentralised machine should be tested with biologic/chemical indicators, soil tests for washers, etc. on a schedule. While CSSD staff routinely do this for their machines, it can be harder to implement across many ward machines without a coordinating mechanism. The net effect may be to encourage centralisation or at least central oversight of all machines, some hospitals assign CSSD staff to also oversee ward decontaminators’ testing. It certainly elevates the required diligence for combination machines: for example, a bedpan washer must achieve the Ao600 disinfection level or it wouldn’t be considered compliant. Knowing this, facilities will choose only those combination machines that are validated to the standard.

Infrastructure and Design Requirements: As noted earlier, AS 5369 lays out expectations for reprocessing area design including one-way flow from dirty to clean, and physically separated areas. In a full CSSD, this is achievable by architectural design. But in a ward utility room, separation is minimal, often one room serves both dirty and clean tasks. This raises a compliance challenge: how to ensure that decentralised reprocessing doesn’t compromise sterility due to inadequate segregation. Some solutions include having closed containers for transporting cleaned items back, or dedicating certain times/areas for dirty vs clean. Nonetheless, to truly meet the ideal, a ward might need renovation e.g. building a wall or adding ventilation. Many hospitals have been grappling with this under AS/NZS 4187’s implementation, whether to upgrade every utility room (expensive) or funnel more processes to CSSD where conditions can be controlled. The new standard’s emphasis on risk assessments means a hospital might, for example, decide that it’s too risky to do any sterile packaging in a ward space that is not properly controlled, and thus require that all instrument packaging and sterilisation happen in CSSD. Meanwhile, they might accept that bedpan cleaning in the dirty utility is low risk as long as proper PPE and hand hygiene are used since sterility is not required, just disinfection. These kinds of nuanced decisions are what the standard expects facilities to think through. Essentially, the stricter the environmental requirements, the more likely facilities are to centralise critical reprocessing, because only in a CSSD can they fully implement those a ward would find it hard to have true “unidirectional airflow” for example. We may see, in coming years, Australian hospitals removing small sterilisers from wards if they can’t satisfy the new room standards, opting to route everything via CSSD, or conversely, upgrading a few strategic ward areas to meet the standard for specific needs like a small satellite sterilisation room in a day surgery wing that’s separate from main CSSD but built to standard.

Documentation and Traceability: The standard reinforces the need for tracking of each load and instrument, as well as policies for storage, transport, and handling of sterile goods. This is a burden that a CSSD is equipped to handle often digitally, but which could be onerous for scattered machines. For example, if a ward nurse runs a small autoclave, they should log load details, chemical indicator results, etc., and maintain those records. Many clinics and wards lack electronic systems for this and may do it manually if at all. To be fully compliant, those records should integrate into the hospital’s quality system. This again encourages consolidation of the process. Additionally, if there is an incident like a steriliser failure leading to a recall of items, a centralised system can more easily identify and retrieve affected items since CSSD controls distribution. Decentralised systems would require each ward to manage its own recall, which might be less reliable.

Training and Personnel: AS 5369 highlights the importance of annual training in infection control and reprocessing for staff. Also, competencies must be maintained. This means if nurses are expected to use a steriliser, they need regular training updates and perhaps even certification. Many facilities may decide it is better to restrict use of sterilisers to CSSD personnel or have CSSD manage those tasks, rather than continuously training a broad swath of clinical staff. On the other hand, the standard’s focus on risk management might allow innovative staffing models, e.g. a hospital might create a “decentralised reprocessing team” that roves between departments to handle reprocessing on-site but under central supervision. Regardless, investing in human resources is necessary for whichever approach, and the known shortage of sterilisation-qualified staff in Australia puts pressure on finding efficient models. Centralisation can partially alleviate the shortage by concentrating the workload to a smaller number of specialists, whereas decentralisation would require training many more people to a basic level something currently challenging given workforce constraints.

In summary, the recent Australian standards changes reinforce a high bar for both methods, without explicitly mandating one or the other. The emphasis is on patient safety, which can be achieved via any configuration if done properly. However, the practical difficulty of meeting all requirements in multiple locations tends to make central CSSD the path of least resistance for critical item sterilisation. Meanwhile, combination washer-disinfectors for bedpans and non-critical items remain invaluable and are validated to align with the standards for disinfection processes. The end result is likely a continued hybrid approach: centralise what must be absolutely sterile and controlled, decentralise where it’s safe and effective to do so with oversight. Each facility must “make choices that meet their needs and means”, as one international review noted, considering factors like infection risk, infrastructure, and budget.

Conclusion and Recommendations

There is no one-size-fits-all answer to the choice between using combination machines for sterilisation/disinfection versus relying on a central CSSD, each approach has distinct advantages and disadvantages, and most healthcare institutions in Australia will employ a mix of both to some degree. Combination machines and decentralised reprocessing offer immediacy, convenience, and targeted solutions especially for patient waste management and small clinics, but come with challenges in maintaining consistent quality, higher cumulative maintenance needs, and potential inefficiencies if not well-utilised. Central CSSD services deliver high-throughput, standardised sterilisation with expert oversight and economies of scale, yet they require significant investment, can introduce delays for remote units, and represent a single locus of dependency.

The decision on how to balance these approaches should be guided by a thorough risk and cost-benefit analysis. Key considerations include:

Infection Control Risk: Minimise the handling and transport of contaminated items to reduce infection transmission. Decentralised bedpan processing clearly wins here for routine patient care, whereas centralised instrument processing wins for ensuring sterility of surgical tools. High-risk items (critical devices) should be reprocessed in the most controlled manner available, which often points to CSSD, while non-critical items can be safely handled in ward utility rooms with proper equipment.
Utilisation and Volume: Evaluate the volume of items to reprocess. High volumes favor centralisation to gain efficiency and justify the infrastructure, whereas very low volumes might be handled in-house with a small unit rather than running a half-empty large machine. If a machine in a ward is rarely used, consider whether that function could be centralised or shared to save cost. Conversely, if a particular ward constantly needs rapid reprocessing e.g. an endoscopy suite needing quick scope turnover, it may warrant its own dedicated machine.
Cost and Budget Impact: Consider both capital and recurring costs. Decentralised options may spread out costs but could sum up to more in maintenance and training. Central CSSD has high upfront cost but can be cost-effective long-term for large facilities. An informed decision will account for manpower, utilities, consumables, and potential downtime costs like surgery delays or purchasing extra instrument inventory as a buffer. Sometimes a hybrid model provides the best cost compromise, e.g. centralise expensive processes but allow simple ones locally to avoid diminishing returns.
Compliance and Standards: Ensure whichever approach is chosen can meet the requirements of AS 5369:2023 and related guidelines. If a facility finds it cannot maintain standard-compliant conditions in wards lack of proper ventilation, difficulty documenting cycles, etc, it should centralise those processes. Use the flexibility of the risk-based standard to prioritize critical gaps first. For example, one strategy might be: centralise all instrument sterilisation to meet sterility assurance levels, but keep ward disinfection for bedpans with improved training and periodic audits. This aligns with meeting standards for critical devices while pragmatically managing non-critical items.
Reliability and Contingency: Plan for equipment failures and staff absences. Central CSSD should have backups or inter-hospital support agreements; decentralised sites should have contingency protocols e.g. if a ward washer fails, use disposables or send items to another ward or CSSD temporarily. Evaluate which scenario poses greater risk to patient care if something goes wrong, and mitigate accordingly. Often, the impact of a single ward machine failing is lower (localized) than CSSD failing (hospital-wide), but CSSD is easier to protect with redundancy. A combination of both robust CSSD plus some local capability can provide resilience (CSSD covers most needs, local machines handle immediate issues or overflow).
Training and Culture: No matter the model, invest in staff training and a culture of safety. If using combination machines, ensure all users understand their importance and operate them correctly. If centralising, maintain good communication between CSSD and clinical staff so that needs are met and any issues like missing instruments or delays are addressed collaboratively, not worked around unsafely.

In Australian healthcare settings, one often sees bedpan washers in every ward (for infection control and convenience) AND a central CSSD for instruments. This appears to be a balanced solution that leverages the strengths of each approach. For smaller facilities, the choice might tilt more towards combination machines due to feasibility, but with careful adherence to standards and perhaps partnerships with larger CSSDs for periodic audits or processing of complex items.

Ultimately, as found in international reviews, “recommending a single [universal] method would be inappropriate”. Both centralised and decentralised methods have benefits and drawbacks, and multiple variables: infection risk, volume of use, infrastructure, staff, geography, budget come into play. Each healthcare facility must define its own needs and make an informed choice, often a “mix-and-match”, to ensure patient safety is maintained at the highest level while operating efficiently and sustainably. By applying a risk-managed approach and staying aligned with standards, Australian healthcare providers can confidently harness the advantages of combination machines where suitable and central CSSD services where necessary, achieving a robust sterilisation system that underpins excellent care.

Sources

Lobe, C. Comparative analysis of bedpan processing equipment (AETMIS technical report summary), 2009
Research by Saif et al. - Centralized vs. Distributed Sterilization Service: location–allocation model, 2013/2018
RACGP / NSW Health - Guidelines on sterilising reusable instruments in office settings.
Safety and Quality (Aust Govt) - Transitioning from AS/NZS 4187:2014 to AS 5369:2023, Aug 2024.