Control measure Firefighter decontamination: Biological agents
Control measure knowledge
This control measure should be read in conjunction with Hazardous materials - Firefighter decontamination.
For generic information on decontamination, See National Operational Guidance: Hazardous materials Hazards – Contaminated members of the public and Contaminated responders.
Although materials that may contain biological agents – such as sewage or bodily fluids – can be seen, biological agents themselves are invisible to the naked eye. Decontamination may be as simple as washing with soap and warm water (using non-alcohol based cleaners on the incident ground). However, as the level of biological agent increases (such as hazard Group/Class 3 and 4 materials), the importance of decontamination will also increase, which will be more likely to require procedures that will kill the biological agent.
However, as biological agents are invisible to the naked eye, determining the effectiveness of decontamination system may become so difficult as to be deemed not cost-effective and, as such, disposable personal protective equipment (PPE) becomes a significant consideration. The only effective way to determine if decontamination has been successful (for high hazard group materials) would be to test swab the entire surface of the PPE and attempt to grow cultures from the swabs; this is not a practical solution. For PPE that has been contaminated with sewage and/or bodily fluids, etc. normal PPE laundry processes will be sufficient to clean the total surface area; combined with instructing personnel to shower with soap and water, this will be the most effective way to complete decontamination. For impervious PPE options (liquid-tight or gas-tight suits) introducing a suitably-based decontamination additive would be necessary as this is the most recognised method of killing biological agents. However, some biological agents will be resistant to decontamination and a significant ‘contact time’ will also be required.
It should also be noted that whilst a chlorine-based disinfectant is suitable for most applications there are organisms where it is not effective, tuberculosis being an example.
A ‘contact time’ is the amount of time the biological agent needs to be in contact with the suitably-based additive to kill the agent. The time may vary, and can range up to 20 minutes depending on the agent involved. This becomes difficult for decontamination, as it entails keeping the personal protective equipment (PPE) wet with the additive for the recommended duration; when the wearer is waiting for extraction this becomes a significant issue. Advice from subject matter experts should be sought, to determine how long a contact time is required. It may be necessary to carry out a controlled removal from the PPE with expert advice. This could include dousing the PPE with a chlorine additive, removing the PPE, and then leaving it to soak for the required ‘contact time’; Confirmation that the decontamination process has been successful will still be required.
For biological agents such as hazard Group/Class 3 and 4, where contamination has occurred it may be better to use disposable personal protective equipment (PPE). Decontamination will then consist of either a safe undress or a wet decontamination with a chlorine-based or other additive followed by a safe undress; the PPE should then be sent for disposal via incineration.
Provide equipment for decontamination against biological agents
Make arrangement for responders to access decontamination additives at the incident
Introduce decontamination additives for biological agents that provide a free-chlorine-based option
Consider firefighter decontamination arrangements for biological agents prior to committing personnel to the hot zone