lighting - it is a physical quantity that characterizes the ratio of the light flux incident on the surface to its area.It being understood that the plane of the surface must be perpendicular to the axis of the light flux.
addition to hygienic values directly to humans, almost light measurement are used in animal husbandry to create a proper indoor climate, in the breeding of aquarium fish and plants for growing indoor plants, to describe the characteristics of the photographic and video equipment, including camera surveillance.
Sources of illumination
known that there is a natural and artificial lighting.It creates the appropriate light sources: refers to the natural ambient light of the sky, of course, the sun and the reflected light of the moon.Artificial sources - different lamps (incandescent, discharge, fluorescent), TV screens and computers.
Why do I need to measure illuminance
lighting - one of the most important health indicators, which depends on the human health.Light metering - a procedure included in SanPiN (sanitary rules and regulations), always made in the workplace on an equal basis with measurements of noise, vibration, dust and gas pollution.
Doctors say that the lack of coverage leads to loss of visual acuity, fatigue, reduced concentration and overall productivity, even cause an accident.The animals and birds of the lack of illumination is impaired growth, development, poor weight gain, reduced productivity (for farm animals) and the ability to reproduce.
How and in what units is measured by the physical quantity
Light metering device is performed, which is called the light meter, a portable device is a variation of the photometer.Modern high-end devices are supplied filters.Unit-light in the international system of units (SI) - suite, which is a ratio of 1 lumen to the square meter of surface area.The measured value of lumens of light flow.The American and British measurement systems are used, such lighting units as lumens per square foot, foot-candle (degree of light from the light source power of 1 candela, defended 1 foot from the surface).
How to measure the illumination?This is done using light meter, the meter must be the last in a horizontal position, place it in the required points of the room.For buildings and livestock facilities, there are special prescribed by state standards in the control of the measuring point.Use the instructions to the device, when using attachments you need to consider the attenuation factor, which is multiplied by the result.Then, different formulas are calculated the minimum, average, maximum illumination, as well as the ratio of natural light.
