Scene survey: Hazardous materials

Control Measure Knowledge

This control measure should be read in conjunction with Situational awareness


The initial scene assessment at a potential hazardous materials incident must be carried out from a place of safety to avoid responders becoming contaminated or exposed to a hazardous material and becoming part of the emergency.

It is necessary to find out what has caused, or is causing, the emergency or event then to estimate foreseeable developments and consequences, who and what will be adversely affected. To assist with this, responders should consider retrieving hazard and incident information from:

  • Placarding and signage, for example:
  • The Dangerous Goods Emergency Action code List (EAC)
  • The Globally Harmonised System (GHS)
  • United Kingdom Hazard Information System (UKHIS)
  • Workplace exposure limit signs
  • Safety Data Sheets (SDS)
  • Transportation documents, for example instructions in writing (IIW)
  • A responsible person

They should also assess the condition of the containment system, in particular:

  • Construction and operation of road, rail and other transport containers
  • Construction and use of fixed storage tanks
  • Construction and operation of intermediate bulk containers (IBC)
  • That pressurised containers are inherently higher risk than non-pressurised
  • Type of stressors involved (for example, direct flame impingement, heat, cold, chemical, mechanical, shock, friction)
  • The operation of any engineered solutions or safety devices fitted, such as pressure relief valves

As part of their scene survey, incident commanders and other deployed personnel should be vigilant for indications that hazardous materials may be present in unexpected locations. Such instances may include, but are not exclusive to, the following:

CBRN materials

Substance assessment

The information received from initial reports regarding the characteristics of any substance causing concern, will help to categorise and potentially lead to subsequent identification of the substances.

The BAD COLDS tool may be used to support this process, even prior to the deployment of specialist resources.

B – BEHAVIOUR – What did the substance behave like? Did it fall to the floor in a soggy lump or behave like smoke vaporising into thin air?

A – APPEARANCE – Is it powder-like, granular or crystalline, is it a liquid, a gel or a waxy solid? How much is there relative to a commonly recognised item, for example postage stamp, A4 sheet etc.

D – DISSEMINATION – How was it disseminated? Thrown, sprayed, mechanically spread or delivered?

C – COLOUR – Is it pure white, off-white, yellow or multi-coloured?

O – ODOUR – Did it smell? Under no circumstances should responders deliberately smell a substance as a means of determining whether it has an odour or not.

L – LIKENESS – Does it look like something you know or recognise?

D – DELIBERATE – Did the spreading or release of the substance appear deliberate or accidental?

S – SYMPTOMS – Is anyone exhibiting any symptoms?

Under no circumstances should frontline responders be further exposed to known or suspected hazardous substances in order to obtain the above information. It may not be possible to carry out a full assessment during Initial Operational Response (IOR). This includes being asked to determine if there is an odour.

For more information refer to the JESIP Initial Operational Response (IOR) to Incidents Suspected to Involve Hazardous Substances or CBRN Materials.

Illicit drug laboratories

Clandestine locations may be established to produce illegal substances which could range in size from one room to a sophisticated operation. Indicators may include covered windows, strong odours, refuse containing chemical containers and occupants reluctant to allow entry to responder agencies, or a more formal laboratory setup such as scientific apparatus, beakers, mixing bowls, fans, eye protection, filter paper and scales. Where a more formal laboratory layout has been identified, then this should not be confused with the manufacturing of improvised explosive devices; they share very similar equipment and should be confirmed as soon as possible.

Improvised explosive devices (IED)

Personnel may inadvertently encounter bomb factories whilst responding to other types of incident or could be called to deal with a suspected or confirmed improvised explosive device. An IED can take the form of a packed device, a vehicle or a suicide bomb.

Improvised explosive devices usually comprise of a range of homemade explosives, rather than standard commercial or military grade explosives. The main types are:

  • Ammonium nitrate-based
  • Sugar chlorate
  • HMTD (Hexamethylene triperoxide diamine)
  • TATP (Tricacetone triperoxide peroxyacetone)

These mixes can be highly unstable and may be sensitive to friction and heat, with the potential to self-heat (known as thermal runaway). Where personnel encounter an improvised explosive device during an incident it is imperative that the device is not touched in any way and the scene secured and evacuated.

During a scene survey certain material may be identified which would indicate or confirm the presence of an improvised explosive device, such as:

  • Chemicals containing chlorates, ammonium nitrate, acetone (solvent/nail varnish remover), Acid (drain cleaner, battery acid), hydrogen peroxide (hair bleach) etc.
  • Bomb making equipment, including detonators (improvised, such as bulbs), power sources (such as batteries), simple switches plus wiring and fragmentation material (such as ball bearings, nuts, bolts and nails)
  • Bomb making paraphernalia or literature such as textbooks, notes, extremist material, academic material or scientific publications
  • A similar laboratory setup to illicit drugs

Individual Chemical Exposure (ICE)

These are events where an individual uses a chemical or a mixture of chemicals with the intent to self-harm, predominantly by ingestion or inhalation. They commonly occur in sealed or partially sealed environments such as vehicles, residential bathrooms, hotel rooms and other enclosed areas where a small amount of gas can quickly reach lethal concentrations.

It is important to note that the signs or indicators of individual chemical exposure may not be immediately obvious. However, there may be certain indications during a scene survey that could help confirm it such as:

  • The signs and symptoms being displayed by casualties and their severity
  • Casualties or emergency responders experiencing breathing difficulties or irritation to the eyes and nose
  • The event taking place in an unusual location such as a vehicle parked in a beauty spot or remote rural area or a small enclosed room
  • Information received (for example from a witness) that a person at the scene may be in possession of chemicals or that there is some history or intelligence that suggests the person has attempted to self-harm on a previous occasion
  • Warning notes or safety data taped to vehicle or building windows or doors
  • Duct tape, plastic or towels used to cover air vents windows and doors to produce a sealed environment
  • Vehicle occupants appearing unconscious or unresponsive
  • Presence of a ‘suicide bag’ or hood at the scene
  • Suspicious (possibly spilled or empty) containers or cylinders
  • Unexplained vapour in the air or a strong chemical smell such as the smell of rotten eggs, bitter almonds, garlic or decaying fish
  • The presence of a barbecue within a sealed or partially sealed environment
  • Disabled smoke or carbon monoxide alarms

White powder or suspicious substance incidents

A ‘white powder’ incident can actually be a powder of any colour. It is a suspicious and unidentified powder that is known to be neither explosives nor drugs. A suspicious substance is an unidentified solid, liquid, gel, crystal, organic or granular material not believed to be explosive or drugs.

The role of the fire and rescue service at these incidents is to support the police service by providing a range of resources and personnel to perform the detection, identification and monitoring of the substances. If at any point during the process it is suspected that the item or substance may be explosive in nature or may in fact be some form of incendiary or improvised explosive device (IED), guidance for explosives or IEDs should be followed and the information communicated to update the joint understanding of risk. This will allow the threat assessment for the incident to be updated.

Following the request to attend an incident, the nature and seriousness of the circumstances will determine the level of specialist assets that a fire and rescue service may deploy. Early multi-agency information sharing is essential, particularly between other emergency services who may also be preparing for a response to the incident or have prior knowledge of the incident. It may be beneficial to deploy a National Inter-agency Liaison Officer (NILO) to provide advice (either at the scene or remotely) on the capacity and capability to support incident resolution.

The police will co-ordinate any multi agency response and ensure that a suitable environment exists before the fire and rescue service or ambulance service provide their respective specialist capabilities. The police will also co-ordinate the threat assessment as they have the capability to access, analyse and disseminate information and intelligence.

Forensic management of incident scenes will need to be considered before the deployment of multi-agency resources where criminal intent or terrorism is suspected, though maintaining any lifesaving activity is the highest priority. Some individual police forces use their own detection, identification and monitoring (DIM) capability (sometimes in conjunction with fire and rescue services) to carry out initial scene assessment under police supervision to mitigate the risk of forensic evidential loss

Strategic Actions

Tactical Actions