Microbiological items in the laboratory workflow help make landmark discoveries, but they need to be managed safely when they enter the waste workflow.
RPS 233 is a regulatory position statement (RPS) that affects all laboratories managing microbiological products. They still need an environmental permit for waste regulation, but following RPS 233 to the letter is ultimately more important.
We have laid out the steps every laboratory needs to take to remain compliant, relating to all relevant guidance. With these steps, your team can stay up to date and confident in the workflow.
Who does RPS 233 apply to?
RPS 233 affects all laboratories that manage microbiological items. It covers the treatment of microbiological cultures and contaminated waste items by autoclaving prior to disposal.
The steps laid out in RPS 233 affect the entire workflow after an item is no longer needed for laboratory use. The Environment Agency intends to review the RPS by 1 August 2026, so it is subject to change, and laboratory teams should regularly check for any amends until then too.
How does RPS 233 affect sterilisation?
How does RPS 233 affect sterilisation?There is a clear focus on autoclaving for RPS 233. Microbiological laboratory waste can present a range of risks to human health, animal health, and the environment.
Laboratory teams will be well versed in steps such as the use of PPE and sufficient ventilation to avoid contamination. Autoclaving an item uses heat and pressure over time to destroy pathogens and sterilise items, meaning microbiological waste has fewer hazardous properties, and can be safely discarded.
RPS 233 requires laboratories to complete this on the original site of production, and limits each site (not each autoclave) to no more than one tonne of waste sterilised in this way per day. If this cannot be followed, the laboratory must tell the Environment Agency immediately for further guidance. According to Health Technical Memorandum 07-01 (HTM 07-01), an audit should be carried out to assess the risks that this may present to team members.
A standard operating procedure for autoclaving waste items should be specified. Guidance from the Health and Safety Executive (HSE) gives all of the details that should be laid out, including the checks that are made and reported, and whether biological and chemical indicators are used.
Containment Level 4 laboratories handle pathogens of great risk, and so require strict autoclaving procedures. Further guidance is offered by the HSE.
What happens if an autoclave malfunctions?
Waste management workflows always need a backup plan, including when the autoclave malfunctions or breaks down. Microbiological cultures need to be appropriately packaged for carriage and transferred to an incinerator as soon as possible in this instance.
What happens after autoclaving?
Once an item has been sterilised, it can be disposed of into the waste streams laid out by HTM 07-01. The use of an autoclave removes the hazards that would otherwise make microbiological waste suitable for infectious or highly infectious (orange and yellow) waste streams. Instead, they are considered offensive waste, which is designated a yellow and black (tiger stripe) bag.
When a laboratory technician is disposing of a sharp item, a sharps container must be used, to reduce the risk of injury. Sharps waste is not classed as offensive waste.
Containers for microbiological waste with Initial Medical
Choosing appropriate waste storage is key for each laboratory. Containers should comply with the HTM 07-01 colour code, be suitable for the physical properties of each waste item, and be easy to transport.
Initial Medical, a leading healthcare waste management service in the UK, provides a wide range of solutions for laboratories. You can find tiger stripe waste bags alongside the tiger stripe Bio-bin® range, which are paper-based solutions that are lightweight and easy to store onsite. Each Bio-bin® has an integrated Bio-matt™ to absorb excess fluid, and they come in a wide range of sizes to suit clinical, pipette and loop disposal in laboratory environments.
Learn more about microbiological waste disposal by contacting our expert team today.