Overview of CBRN part 4

Within the CBRN context there are many processes which staff should be aware of to help with their management, safety, and wellbeing at the incident. As already mentioned, a CBRN event will create a huge multi-agency response with various aspects and safety considerations not previously thought of. In these next two sections, we’ll cover some of the mnemonics and considerations needed to help you at a CBRN incident. For greater in-depth information, your Ambulance Trust/Organisation will have significant data available on their operational plan for CBRN events.: 

Considerations when dealing with a major incident involving CBRN: 

Dealing with a CBRN incident involves a wide array of considerations and actions which will all vary depending on the substance and circumstances. Significant safety parameters will be needed, along with communication to an array of specialists and organisations. We can’t cover the wide range of considerations completely in this course due to the vastness, but here are some to starts with: 

  • Safety 
  • Consider your own safety throughout the event. It’s easy to be tempted to rush in and help but if you become a casualty, you cannot organise the initial emergency response and coordination needed. In a CBRN incident, specialised PPE above that of standard Ambulance PPE will be needed. Specialist organisations and responders will be needed to identify the substance used and what level of protection is needed. Weather reports will be required to plot potential contamination of substance over a wide area. Natural resource organisations will be required to review waterways and where substances may contaminate. This and much more will be needed to review your and others safety 
  • Location 
  • Consider how your location may affect the organisation of the major incident. Are you able to have a good overview of the scene to manage resources and gather information. Are you able to identify other emergency service responders and managers where you are and co-locate with them. Is there enough space where you are for other services to enter the area. Is your current location safe? You may not want to be in clear view if there are people armed with weapons. If it is a CBRN event with aerosol/gaseous substances, you need to try and be upwind from the incident so to stop potential contamination from CBRN substances in the air. Your location and positioning could significantly affect the overall management and running of the major incident 
  • Zoning 
  • Consider what may be the ‘Hot’ zone, where there is immediate danger, ‘Warm’ zone, where the risk of danger still may be possible, and ‘Cold’ Zone, where there is no danger. Being aware of zoning could help you with initial planning and management of a CBRN major incident. Do you have appropriate PPE and training to enter a warm zone, or do you have to maintain discipline and stay in the cold zone? Is there risk of the zone areas changing or new threats become present, for example, an explosion risk 
  • Generally, any management and organisational structures on scene will likely remain in the cold zone. Responders will operate in the warm zone, and specialists will be in the hot zone. This will all depend on the CBRN element and risk/circumstances present 
  • Casualties 
  • On arrival at the incident, there may be many casualties wanting to approach you. Keep everyone calm and give them reassurance that more help is on the way. Although difficult, you need to keep everyone at a distance from you and the operating area, so you don’t become disrupted, block the access/egress, or even contaminated by CBRN substances on the patients. You may have to designate areas for walking casualties to collect, while also considering what level of CBRN contamination they may have present. Apply the ‘Remove’ (covered in the next section) modified decontamination process and try to contain all contaminated patients in one area awaiting further decontamination form specialists. 
  • Multi-organisational response 
  • After declaration of a major incident, further emergency service resources will be quickly arriving on scene. Follow the Joint Emergency Service Interoperability Principles (JESIP) and effectively coordinate and communicate with them to organise your next actions moving forward. Ensure clear and simple communication is used throughout so there is no confusion to any information given or decision made. Try not to use mnemonics/confusing jargon, and if you are unsure of anything, ask for further clarification  
  • Allocating a loggist, or taking notes from communication and decisions made is a vital aspect as you can pass on to arriving ambulance commanders in detail what has been discussed and decided. The logs/notes you make will be used in later investigations as evidence of the events on the day. You will likely have to present your account of the incident and having logs/notes will help you in giving an accurate testimony.  



If you’re first on scene of a CBRN incident, consider scene management and use of the METHANE report. METHANE is the declaration of a major incident and gives a detailed report that can help organise a multi-agency response. The METHANE report goes as follows: 

  • (M) Major incident declared/standby 
  • This gives your Ambulance Control Centre the information that you are declaring a major incident, or are putting them on standby for a potential major incident 
  • (E) Exact location 
  • This gives the exact location of the incident so Ambulance Control and other emergency organisations can start to coordinate, plan, and respond. It may be difficult to give an exact location if not immediately obvious, so consider using a grid reference, landmarks, further apps, or vehicle plotting to help 
  • (T) Type of incident 
  • This gives the type of incident that is currently ongoing. This helps identify what emergency services are required, what specialist teams can be sent, what resources may be needed, and so forth. Explaining the type of incident can be in simple terms, e.g., terrorist attack using chemical weapons 
  • (H) Hazards 
  • This again gives information and knowledge of what services may be required, and what emergency responders need to be aware of when turning up at scene 
  • (A) Access and egress 
  • This gives Ambulance Control details of what may be the best access to and from the site. This can then be shared among other emergency services and responders 
  • (N) Number of casualties 
  • This is a close estimation to the number of casualties you believe are involved in the incident. This helps with organising the number of emergency resources that may be needed 
  • (E) Emergency services required 
  • This is what emergency services you feel may be required given your first-hand information from scene 


On declaration of a major incident, a cascade of actions and responses will occur to start the immediate containment and management of the event. If you are first on scene and have declared a major incident, you will have to take the role of on scene commander, managing the scene, and liaising with other clinicians and services until an appropriate manager arrives to take over from you.