Pollution incidents and environmental damage

Preventing pollution from firefighting


Fire is a serious risk to the environment. You should always try to reduce the risk of fire and the damage that fire and firefighting could cause.

To prevent pollution from firefighting you should:

Deal with polluting foams safely

Perfluorooctane sulfonate (PFOS) is a chemical used in aqueous film forming foam (AFFF) which is highly polluting if it escapes into the environment. AFFF foams were used to fight fires involving flammable liquids like fuel (Class B fires).

PFOS has been phased out and is no longer available on the market. Alternative products are available.

Due to their potential to harm the environment it is good practice to return foams containing PFOS or PFOS related substances to the manufacturer for disposal by incineration.

When you test fire extinguishers or carry out firefighting exercises you must not allow used foams to enter drains, surface waters or groundwater. You must contain them for disposal off site or you may be able to get approval from Northern Ireland Water (NIW) to discharge foam into the public foul sewer.

How to control firewater

Firewater is polluting and you may need to deal with it as hazardous waste.

You must not discharge firewater into the environment. Ensure you have a plan and equipment in place to collect or contain it in the event of an emergency.

Store firewater correctly and ensure that it is treated and disposed of by a permitted or licensed waste management business. You may also be able to get permission from NIW to discharge it into the foul sewer.

To prevent firewater from running into surface drains, polluting nearby waterways (rivers, streams and groundwater), foul drainage systems, and land, you should:

  • construct containment lagoons, tanks or systems on impermeable surfaces to hold firewater
  • isolate containment systems from surface drains, waterways, land or sewers

Read HSE guidance on the secondary containment of firewater.

NIFRS may consider a controlled burn to minimise water and air pollution.