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Health and Safety at Work Act etc. 1974

Ionising Radiations Regulations 1999
Certificate of Approval No TA1 of 1999

1 By virtue of the powers conferred on it by paragraph 1(c) of Schedule 1 to the Ionising Radiations Regulations 1999 ('the Regulations'), the Health and Safety Executive approves the type of apparatus specified in Schedule 1 to this Certificate, subject to the conditions specified in Schedule 2.

2 This Certificate shall remain in force until it is revoked in writing by the Health and Safety Executive.

Signed by

Wendy Bines
(A person duly authorised by the Health and Safety Executive to act in that behalf)

Dated this 22nd day of December 1999.


Schedule 1

1 Ionisation chamber smoke detectors containing Americium-241 installed in premises or a workplace.

Schedule 2

1 This type approval shall only apply to ionisation chamber smoke detectors (specified in Schedule 1) that have been shown to conform to all of the requirements for that detector specified in 'Recommendations for ionisation chamber smoke detectors in implementation of radiation protection standards' published by the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD) 1977.


Explanatory notes for certificate of approval No TA1 of 1999

1 These notes do not form part of the Certificate of Approval.

2 Apparatus specified in the Certificate is type approved for the purposes of Schedule 1 to the Regulations. This means that employers who have such apparatus installed in their premises but carry out no other work with ionising radiation need not notify the Health and Safety Executive, and need not consult a radiation protection adviser.

3 The approval does not exempt employers from any of the other requirements of the Regulations.

4 This approval does not relate to the functional ability of the apparatus.

5 The Nuclear Energy Agency publication referred to in the Certificate of Approval (Schedule 2) limits the activity per detector (eg 740 kBq Americium-241 for devices that are not single station detectors) and limits the dose equivalent rate at 0.1m from the surface of the detector to 1 µSv per hour. In addition, the detector must pass certain tests with respect to radioactive contamination on accessible surfaces and the effects of temperature, impact, drop, vibration and fire.

6 This Certificate of Approval is general in application and applies to any type of appliance specified in Schedules 1 and 2. Thus, individual Certificates of Approval will not be required for each type of ionisation chamber smoke detector.

7 An employer can satisfy the conditions in Schedule 2 to the Certificate of Approval if he can show that his appliance is one of a type that was tested on behalf of the manufacturer or supplier by a reputable independent testing body and found to conform to the requirements specified in Schedule 2.

8 It is expected that the manufacturer or supplier will make available to employers at the time of supply/installation, and in the case of existing installations on reasonable request, written information which shows whether or not this type of ionisation chamber smoke detector has satisfied paragraph 7 above.

9 This certificate replaces the Certificate of Approval TA1 of 1990 which expires on 31 December 1999.

10 In the case of apparatus installed on offshore installations (premises referred to in Article 4 of the Health and Safety at Work etc Act 1974 (Application outside Great Britain) Order 1989) a separate Certificate of Approval has been issued on behalf of the Secretary of State for Trade and Industry.

Updated 2016-07-27