This refers to a release of a significant amount of radioactive material or other toxic material.
A klaxon will sound:
- an interrupted note for warning
- a continuous note for the all clear
On hearing the klaxon (klaxon sounds like this):-
- If outside enter the nearest main building
- Remain inside and obey instructions given by the building warden
- Close all windows and doors, skylights and louvres
- Close down ventilation plant or fans
- Do not use the telephone system except for calls connected with the incident or other emergencies
