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Control measure

Treatment: Corrosive materials

Control measure knowledge

This control measure should be read in conjunction with National Operational Guidance: Environmental Protection - Treatment

Neutralisation is a chemical method of making a spill less corrosive by applying a second material that will chemically react with the original to form a less harmful substance. The most common example is applying a base or alkali to an acid spill to form a neutral ‘salt’.

Firefighters should not assume that the salt produced by neutralisation is safe. These salts, while no longer presenting a corrosive hazard, can have other hazards (for example, they may be toxic or explosive).

The major advantage of neutralisation is the significant reduction of harmful vapours being given off. In some cases, the corrosive material can be rendered harmless and disposed of at much lower cost and effort. However, during the initial phases of combining an acid and a base, a tremendous amount of energy may be generated along with toxic and flammable vapours.

When a decision has been made to neutralise a spill, consideration should be given to the type of neutralising agent that will be used. Certain neutralising agents produce less heat when reacting and some materials are more environmentally friendly than others; the key concern is biodegradability. Environment agencies should be consulted prior to any neutralisation tactics being implemented.

Strategic actions

Fire and rescue services should:
  • Consider appropriate arrangements for the provision and use of suitable and sufficient corrosive materials neutralising agents

Tactical actions

Incident commanders should:
  • Attempt to neutralise any release or spill of corrosive materials based on specialist advice

  • Contact and liaise with product specialists to find out if the 'salt' of the corrosive substance from neutralisation will retain or develop further hazards

  • Consult environment agencies before carrying out any neutralisation

  • Control and confine the spill to prevent run-off after application of the neutralising agent

  • Ensure there is sufficient neutralising agent on-scene to complete the process

  • Apply the neutralising agent from the outermost edge inward, thereby protecting responders