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by the NFCC

Control measure
Dilution

Control measure knowledge

In certain situations the best way to deal with domestic quantities of spillage may be to dilute it with a large amount of water. High levels of dilution should ensure that pollutants have little impact on the environment. It is important to consider the pollutant type and quantity, and how sensitive the receiving water is before doing this.

Approval should also be sought from the environment agency and sewerage company before diluting a spillage unless there is an immediate life risk. In such circumstances they must be informed as soon as is reasonably practicable. See Guideline notification criteria Appendix 4, Environmental Protection Handbook

Strategic actions

Fire and rescue services should:
  • Ensure that fire and rescue service managers who are likely to be in command of an incident involving hazardous materials and/or environmental risk, or are likely to perform the specialist advisory role of hazardous materials advisor (HMA), receive specialist environmental training. This training should place emphasis on larger-scale incidents where there is significant environmental risk.
  • Consider mobilising or involving a HMA for any incident with the potential to pollute the environment, not only those incidents involving hazardous materials. See section 3.3, Environmental Protection Handbook.

  • Identify triggers where the local environment agency should be informed or where advice should be requested.
  • Secure access to more detailed advice from scientific advisers or from the CHEMSAFE service provided by the National Chemical Emergency Centre (NCEC)

Tactical actions

Incident commanders should:
  • Contain the spill
  • Seek guidance from environment agencies before any attempt at dilution
  • Not flush spillages down drains without approval from:

    • The local environment agency
    • Sewerage company
  • Ensure that if detergents or other chemicals are added to spillages to assist with clean up or treatment the resulting mixture is not to be flushed down drains.