- Emergency Lighting Summary of the BS 5266.Guide to Wireless Intruder Alarm Batteries.18th Edition of the IET Wiring Regulations (BS7671).Fire Isolator Switch is Now Legal Requirement BS5839.Fire Safety Penalties | The Risks of Non-Compliance.Fire Alarm and Emergency Lighting Testing.Emergency Lighting Non or Maintained Special Offer.Emergency Lighting Summary of the BS 5266.