A light meter is used to measure visible light in units of lux or foot-candles. In photometry, luminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception. Similarly, luminous emittance is the luminous flux per unit area emitted from a surface. Luminous emittance is also known as luminous existence. In SI derived units these are measured in lux (lx) or lumens per square meter (cd•sr•m-2). In the CGS system, the unit of luminance is the phot, which is equal to 10000 lux. The foot-candle is a non-metric unit of illuminance that is used in photography.
GCEEC will conduct light Intensity measurement by using two portable instruments i.e. Digital Light Meter and Digital LUXMETER. Light intensity measurements (in LUX) was performed utilizing Extech Digital light intensity meter (European Class 1 Standard) complying with standards ISO 8995-1:2002(E) CIES008/E: 2001 in accordance to GCEEC Standard Operating Procedures (SOP). And the LUXMETER is complying with standards such as NF EN 12464-1 - Lighting of workplaces (inside), NF EN 12464-2 - Lighting of workplaces (outside), NF EN 12193 - Lighting of sports facilities. A set of three readings were collected and average of which was reported with graphical representation.
6.2 Monitoring Parameters
Light Intensity Level- in LUX and Foot-Candles, Luminance- in LUX and Foot-Candles
6.3 Description of Extech Light Meter
Extech Easy View Digital Light Meter which measures the amount of light falling on surface (illuminance) in Foot-candles or Lux. This device measures up to 20,000 Fc and 20,000 Lux.
Description of LX200 LUXMETER
LX200 lux meter is a photometer for measuring illuminance, it is equipped with a photoelectric detector and with a silicon photodiode coupled with a filter to modify its response and to get it as losed as possible of the reference function V (λ) defined in the CIE (International Commission on Illumination). LX200 is hand-held autonomous instrument fully automatic designed for measuring illuminance. With its memory, it allows the storage of datasets for processing on a computer. Results are displayed in Lux or in foot candle and allow 5 measurement modes:
• Instantaneous illuminance
• Relative illuminance
• Evolution of illuminance according to weather conditions
• Mapping of illuminance ? Spatial representation
• Industries and Factories
• Manufacturing Industries
• Designing (Fine Works) workplaces
• Universities, Schools, Libraries
• Building Security and ATM Area
• Museums and Art Galleries
• Video, photographic and architectural uses
• Federal Law No. 24 (Environmental Protection and Development)
• AD EHS RI-CoP 8.0 - General Workplace Amenities V 2.0
• Dubai Environmental Guidelines