Illuminance Calculation of Fire Emergency Lighting
Illumination requirements for fire emergency lighting fixtures:
① The minimum horizontal illuminance on the ground of the evacuation aisle should not be lower than 0.5 lx;
② The minimum horizontal illuminance on the ground in crowded places should not be lower than 1.0 lx;
③ The minimum horizontal illuminance on the ground in the stairwell should not be lower than 5.0 lx;
④ The minimum illuminance value of fire evacuation lighting installed in evacuation walkways, stairwells, smoke control front rooms, public activity places, etc. in civil air defense projects should not be lower than 5.0 lx
⑤ The fire emergency lighting of the fire control room, fire pump room, self-provided generator room, power distribution room, smoke prevention and smoke exhaust machine room, and other rooms that still need to work normally in case of fire should still ensure the normal lighting illuminance.
Average illuminance calculation formula:
Utilization coefficient method: Eav=φ (single luminous flux) * N (quantity) * CU (space utilization coefficient) * MK (maintenance coefficient) / S (area)
The space utilization factor is generally 0.3~0.4, and the maintenance factor is generally 0.7~0.8;
Unit capacity method: W (required power per unit area to be illuminated) = P (power of all lamps) / S (area to be illuminated)
Replaced by: N (number of lamps) = E (required illuminance) * A (room area) * φ0 (luminous flux per unit area per LX) * C1 (correction coefficient) * C2 (correction coefficient) / φ (luminous flux of a single lamp)
Generally, the illuminance of a study room is 100Lux, but the illuminance required for reading is 600Lux, so it is better to use a desk lamp as a local lighting.
Indoors, the contours of faces can be discerned, the illumination is 20LX, and the illumination for playing chess and cards is 150LX. It takes about 250LX to read a novel, that is, a 25-watt incandescent lamp is 30-50 cm away from the book, and about 500LX is required for writing, that is, a 40-watt incandescent lamp is away from The book is 30-50 cm, and it takes about 30LX to watch TV. Just put a small 3-watt lamp out of sight.
Maintaining proper illumination is of great benefit to improving work and study efficiency; working and studying under too strong or too dark light is harmful to the eyes.
The illuminance used by the same lamp
1). It is related to the type, luminous effect and light distribution curve of the lamp.
2). It is related to the hanging height of the lamp. The higher the suspension, the more reflected luminous flux, and the higher the utilization factor.
3). It is related to the area and shape of the room. The larger the area of the room and the closer it is to a square, the higher the utilization factor due to the more direct luminous flux.
4). It is related to the color and cleanliness of walls, ceilings and floors. The lighter the color, the cleaner the surface, the more light flux is reflected, and thus the higher the utilization factor.
