Royal Navy: Nuclear siren test at Portsmouth Naval Base cancelled

The alarm was due to be raised at 9.30am on February 25. It has been known to be heard throughout parts of the city and outside HMNB Portsmouth on previous occasions.

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These tests are usually carried out on the last Wednesday of February, June, and October, each year. Routine and regular procedures, from Gosport Borough Council and Portsmouth City Council, state the siren is sounded three times a year. Despite these requirements, the test was not conducted at the base.

When asked for clarification, a Royal Navy spokesperson said this was “due to the non-availability of the site wide broadcast system”, which meant it was “not possible to issue the necessary pre-cursor warning to site users that the site nuclear siren test is about to take place”. They added that the siren test needed to be cancelled “on this occasion”.

The alarms test is part of testing the Royal Navy’s nuclear accident response plan for the base. The News has asked why the broadcast system was not available.