Emergency lighting systems in buildings are rarely used but absolutely necessary. When the main power goes out, these units provide light to a safe passage. When the fire alarm bells are ringing and smoke is in the air, these backup lights save lives by preventing people from panicking.
Emergency lighting is a part of a building's life safety system and are standard features in commercial, industrial and multi-residential buildings. After the main power is cut by fire, they provide illumination for a minimum of 30 minutes to allow the building to be evacuated.
Most times the emergency lights are separate from exit signs and their purpose is to:
Emergency lighting is required in high-occupancy residential buildings. The suites do not require emergency lamps but the common areas, corridors and stairwells do.
Emergency lights are powered by a battery-backup system that switch on automatically in a power outage. Remote lamp heads use separate conductors (usually DC) from the main lighting circuits and are spread throughout the tenant space.
Most modern installations use low power, high output LED lamps while the older units still use the incandescent spot lights. All units have a reflector and lens to focus the light along a pathway, not a flood light.
As electrical engineering consultants, we design emergency lighting systems to meet the minimum requirements set out in the building code, fire code and Canadian Electrical Code and then customize the system to the client's situation, special hazards and path of egress.
For instance, in a parcel sorting plant, when the main power is interrupted, the warehouse area will be lit to a minimum of 1 lux while the areas around the conveyors will have added emergency lights to allow workers to safely evacuate from the machinery.
In Alberta and BC, a minimum of 30-120 minutes of battery power is required for these systems, depending on the building designation. Their emergency power source can be a battery or a back up generator, the latter not being as common in this part of Canada.
Both provinces base the requirements for emergency lighting systems on the National Building Code of Canada. There are some minor differences between the provinces but the main similarities of Section 18.104.22.168 that pertain to Part 3 buildings are:
The circuits that power the emergency lighting system must conform to the Canadian Electrical Code section 46. The following requirements are necessary:
Special Case - In some areas of western Canada, power outages are frequent, especially in northern Alberta, the BC coast and Vancouver Island. Depending on the outage duration and the associated risk to those in the building, we use our engineering discretion in determining the type of back power system for the emergency power. This may be more stringent than the minimum set forth in the code to ensure safety. It's important to work with the local fire safety and building inspectors in these rare circumstances (see BCBC/ABC Appendix A-22.214.171.124(1).
Maintenance - The building codes require that your emergency lighting systems be tested monthly to ensure safe operation when really needed. This testing is usually done by electrical contractors and fire alarm companies.
Emergency lightings are essential components of a building's life safety system and are the last systems operating when emergency situations occur. Let's keep lives and livelihoods safe.