Lighting is a crucial safety consideration. A properly lit workplace impacts safety in several ways. It allows machines, vehicles and workers to safely navigate space. It allows employees to clearly see the potentially dangerous machines with which they are working. And, in emergency situations, it clearly communicates walkways, fire escapes, exits, and other potentially life-saving information.

General Lighting

First, we will consider general lighting, that is, the lights which provide basic illumination to a workplace during working hours. Strength of illumination, or how much illumination a lighting system provides, is generally measured in foot-candles. Most workplaces, including construction areas, warehouses, hallways, and maintenance areas, require at least 5 foot-candles of illumination intensity. However, some critical areas, like first aid stations and infirmaries, require as many as 30 foot-candles of illumination intensity. OSHA standard 1926.56 clearly defines the number of foot-candles of illumination necessary for a given workplace:

Foot-Candles |Area of Operation

5............. | General construction area lighting.

3............. | General construction areas, concrete placement, excavation and waste areas, access ways, active storage areas, loading platforms, refueling, and field maintenance areas.

5............. | Indoors: warehouses, corridors, hallways, and exitways.

5............. | Tunnels, shafts, and general underground work areas (Exception: minimum of 10 foot-candles is required at tunnel and shaft heading during drilling, mucking, and scaling. Bureau of Mines approved cap lights shall be acceptable for use in the tunnel heading)

10............ | General construction plant and shops (e.g., batch plants, screening plants, mechanical and electrical equipment rooms, carpenter shops, rigging lofts and active store rooms, mess halls, and indoor toilets and workrooms.)

30............ | First aid stations, infirmaries, and offices.

Exit and Emergency Lighting

Special consideration needs to be given to exit lighting. Functional exit lighting is imperative for maintaining safety in power outages or emergency situations. First, a person with normal vision must be able to see the signs at any point along the exit route. OSHA defines exit routes as “a continuous and unobstructed path of exit travel from any point within a workplace to a place of safety.” This includes doors, stairs, aisles, corridors, and ramps, all of which require proper emergency lighting. Emergency lighting must emit 1 foot candle of light at any point in the building and 0.1 foot candle of light along the emergency exit path at floor level. Furthermore, workplaces must have an automatic, continuous, and reliable light source in place to provide illumination in the event of a power outage. Emergency exit paths must also stay fully illuminated for 1 ½ hours after an outage.

Emergency exit paths also need to be marked with exit signage. Signage is crucial to communicating exit locations, and must be visible from any point along the evacuation path. The signage itself must also be illuminated. OSHA standard 1910.37(b)(6) states:

Each exit sign must be illuminated to a surface value of at least five foot-candles (54 lux) by a reliable light source and be distinctive in color. Self-luminous or electroluminescent signs that have a minimum luminance surface value of at least .06 footlamberts (0.21 cd/m²) are permitted.

The National Fire Protection Agency (NFPA) also sets forth exit guidelines. The most recent standard (NFPA 2013) recommends the use of photoluminescent (glow-in-the-dark) signs to communicate both fire extinguisher and exit locations. Photoluminescent signs provide dependable illumination in power outage or smoke filled situations, and require no external light or energy source in an emergency.

Lighting is a fundamental safety consideration. It allows workers to see their environment and perform their jobs safely. As such, it is important to carefully examine your workplace, make sure all lights are working properly, and all fire extinguishers and exits are properly illuminated. OSHA has provided a brief checklist to help perform this vital task accurately.