Fire

Primary reference(s)

WHO, no date. Technical Hazard Sheet - Technological Disaster Profiles. World Health Organization (WHO). Accessed 23 October 2020.

Additional scientific description

The effects of fires or explosions can be devastating in terms of lives lost, injuries, damage to property and the environment, and to business continuity. Working with flammable liquids, dusts, gases and solids is hazardous because of the risk of fire and explosion (HSE, no date).

Fire-related chemical incidents may also include explosion, spills, leaks and contamination.

Notable examples of fire-related technological incidents include the Piper Alpha oil platform disaster, UK, 1986 (Cullen, 1990), the Kuwaiti oil fires in 1991 (Al-Damkhi et al., 2009), the World Trade Centre fires in New York, USA in 2001 (Klitzman and Freudenberg, 2003), and the explosion and fire at the Buncefield oil storage depot, UK, in 2005 (HSE, 2011).

Fire-related technological incidents can be sudden and acute, when hazardous chemicals are ‘overtly’ released into the environment. The factors leading up to an incident include poor maintenance of manufacturing and storage equipment, lack of regulation and/or poor enforcement of safety regulations, road traffic accidents, human error, natural events such as heavy rain, earthquakes, hurricanes, and floods, and terrorism (WHO, no date).

Most fire-related technological incidents occur at the interfaces between transport, storage, processing, use, and disposal of hazardous chemicals, where these systems are more vulnerable to failure, error or manipulation. Exposure levels will in general be quite different for different people involved in a chemical incident (WHO, no date):

• Employees and other on-site persons: usually more than one exposure pathway, often inhalation of smoke, vapour and skin contact from splashing and clean-up of chemicals
• Emergency services: usually close to the emergency and involved in rescue, containment of chemicals, managing the impact of fires; primary and secondary contamination of fire officers, ambulance officers, other emergency staff; secondary contamination of medical staff and other hospital patients of incomplete decontamination of causalities.
• Public: exposure via air, water, food, soil etc.

Metrics and numeric limits

Not available.

Examples of drivers, outcomes and risk management

Factors that affect the vulnerability of responders and the public include the nature of the hazard, the level of exposure, availability and quality of shelter, availability of Personal Protection Equipment (PPE), access into and out of the site, the degree to which employees and responders (and possibly the public) are prepared and trained to deal with a chemical release and the amount of training provided. Vulnerability can be reduced by ensuring that information is available on: the incident; measures being taken to contain the release; who is currently under threat; what the health effects might be from exposure; what the public can actually do to protect themselves; and how to get further information; when, where and how it will be available (WHO, no date).

Some individuals and sub-populations can also be at increased risk because they are more susceptible to the adverse effects of a given exposure. Among the potential causes of enhanced susceptibility are inherent genetic variability, age, gender, preexisting disease (e.g., diabetes, asthma, chronic obstructive pulmonary disease), inadequate diet, occupational, environmental or lifestyle factors (e.g., smoking), stress and inadequate access to health care (WHO, no date).

In most cases the mechanisms and health outcomes of exposure are unknown. Symptoms may present differently depending upon the products of combustion and chemicals and other material involved in the fire. In general, the adverse health outcomes to toxic chemical exposure may be:

• Effects that are local or arise at the site of contact with the products of combustion and chemicals, such as bronchoconstriction from respiratory irritants, or irritation of the skin and eyes by gases, liquids and solids.
• Effects that are systemic or affect organ systems remote from the site of absorption, such as depression of the central nervous system from inhalation of solvents, or necrosis of the liver from the inhalation of carbon tetrachloride.
• Effects on mental health arising from real or perceived releases, which depend on the psychosocial stress associated with an incident.
• The time elapsing between exposure and the onset of symptoms can vary:
• Some effects, for example eye and respiratory irritation or central nervous system depression, can occur rapidly, within minutes or hours of exposure (acute effects).
• Other effects, for example congenital malformations or cancers, may take months or years to appear (delayed effects).

The duration of the symptoms can also vary, from short-term, to long-term or chronic. Chemical incidents (especially acts of terrorism) may also cause fear and anxiety in populations (WHO, no date).

The World Health Organization (WHO) recommends that risk management measures include: being aware of explosive related hazards; locating chemical sites away from centres of population; registration of all chemicals in commercial establishments with a hazard inventory to ensure rapid identification of the released chemical; regular evaluation of plans and their implementation; inspection/monitoring and enforcement of safety measures; reducing the amounts of chemicals stored; appropriate labelling of all chemicals; rapid notification of the chemical incident emergency services in the event of a chemical release; regular surveillance and standardized reporting of incidents, including the small, commonly occurring incidents ones; measures to decontaminate land or water already contaminated by waste disposal; measures to prevent or contain any fire-fighting water run-off; and construction of drainage ditches or holding tanks to contain liquid chemicals (WHO, no date).

In any chemical incident, there are a number of essential steps to go through as part of the fire related chemical incident plan. These are in an approximate chronological order: alerting the health care services; best outcome assessment of actions and management options; environmental monitoring; public information and public warnings; advice on protection; sheltering or evacuation; other interventions to protect public health; and organising registers and samples.

Preparedness

That careful planning and thorough preparedness are prerequisites for an effective response to chemical incidents. That public authorities, at all levels, and the management staff of installations where hazardous chemicals are produced, stored etc. should establish emergency preparedness plans.

That all responsible parties should ensure that manpower equipment, and financial and other resources necessary to carry out emergency plans are readily available for immediate activation in the event, or imminent threat of an accident.

That all personnel involved in the emergency response process should be adequately educated and trained.

Response

That depending on the level of potential exposure, risk zones are usually established around an incident:

• The hot zone, is the area where first responders must use protective equipment to prevent primary contamination.
• The warm zone, which surrounds the hot zone, is the area where appropriate personal protective equipment must be worn to prevent secondary contamination.
• The cold zone is the uncontaminated area between the inner cordon and the outer cordon where it has been assessed that there is no immediate threat to life.
• The decontamination line separates the warm from the cold zone.

That a vulnerable zone (in effect a potential hot zone) can be declared, which is the area likely to be contaminated if the emergency response action is not successful. The population within the vulnerable zone includes the resident population as well as the working population (in the plant and in the area), and other populations in the area at certain times, such as motorist, tourists and visitors to entertainment facilities.

To contact the nearest Poisons Centre in case advice on diagnoses and treatment of chemical poisonings is needed.

To set-up a public health team which, in case of an fire related chemical incident, will provide accident and emergency departments with information about the nature of the chemicals(s), any precautions to be taken, and information about secondary contamination and how to decontaminate causalities, staff and equipment. Further details and guidance can be found at WHO Manual: The Public Health Management of Chemical Incidents (WHO, 2009).

Designed to help manage the recovery phase of a chemical incident where contamination has affected food production systems, inhabited areas and water environments, further information can be found in the UK recovery handbook for chemical incidents (PHE, 2020).

The WHO works closely with countries and partners to monitor and report on their emergency preparedness capacities for all hazards, including for chemical incidents. Surveillance of diseases of possible chemical etiology is a daily element in WHO’s outbreak alert and response activities (WHO, 2020).

The WHO also convenes regional meetings to strengthen the global network of poison centres and thus facilitate emergency responses to chemical incidents. Guidance and training materials to strengthen preparedness for chemical incidents and emergencies have been developed in collaboration with the Organisation for Economic Co-operation and Development, the Inter-Organization Programme for the Sound Management of Chemicals, and relevant organizations in the United Nations system (WHO, 2020).

Additional resources include the WHO human health risk assessment toolkit for chemical hazards (WHO, ILO and UNEP, 2011) and the guidance document on evaluating and expressing uncertainty in hazard characterization (WHO and IPCS, 2018).