Nuclear Substances and Radiation Devices Regulations

6 A person may, without a licence to carry on that activity, possess, transfer, use or abandon a smoke detector that contains a nuclear substance, if

• (a) the smoke detector does not contain more than 185 kBq of americium 241 or, where it is in a commercial or industrial facility, more than 740 kBq of americium 241;

• (b) the radiation dose rate does not exceed 1 µSv per hour at 0.1 m from any of the accessible surfaces of the smoke detector;

• (c) the design and construction of the smoke detector prevent persons from making direct contact with the nuclear substance that it contains under normal conditions of use;

• (d) all markings and labels on the smoke detector are legible;

• (e) the radioactive nuclear substance contained in the smoke detector is a sealed source that, when it is mounted in its holder, conforms to International Standard 2919, Radiation Protection — Sealed radioactive sources — General requirements and classification (1999), of the International Organization for Standardization; and

• (f) the smoke detector meets the tests specified in the annex entitled Prototype Tests of the Recommendations for ionization chamber smoke detectors in implementation of radiation protection standards (1977) of the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development.