Intervention for recovery, application of ERLs, gamma dose rates

Information on intervention for recovery after accidents, emergency reference levels (ERLs) and the investigation of abnormally high gamma dose rates.


Documents of the NRPB Volume 8 Number 1: intervention for recovery after accidents

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This document comprises 3 sections:

Intervention for recovery after accidents

The document provides a framework for developing protective strategies in the longer term following an accidental release of radionuclides to the offsite environment. The advice covers all forms and scales of accidental release, including releases from nuclear sites and reactors, weapons accidents, and damaged industrial or medical sealed sources. The countermeasures considered are those intended to protect the public from external irradiation from radionuclides deposited in the environment, from the inhalation of resuspended radionuclides, and from inadvertent ingestion of radionuclides resulting from contact with contaminated surfaces.

Application of emergency reference levels of dose in emergency planning and response

The document also provides guidance on how it is intended that emergency reference levels (ERLs) should be applied in the development of emergency plans. In particular, specific guidance is developed in the following areas:

  • how to incorporate the concept of averted dose in emergency plans
  • the choice of dose quantities to be compared with the ERLs
  • the use of ERLs in the event of an actual accident

Only in the unlikely situation of a serious accident for which there was no emergency plan which could be activated should the ERLs be used as direct criteria, and then only for determining the most urgent response.

Identification and investigation of abnormally high gamma dose rates

Following the accident at the Chernobyl nuclear plant, many organisations in the UK established their own automatic environmental radiation monitoring networks. Their aim is to detect and measure any increases that might be caused by a nuclear or other radiation accident. This is commonly achieved by comparing measurements of gamma dose rate with a predetermined reference level.

Published 15 July 2012