Luminary distribution luminaries may be classified according to how they distribute the lot admitted by their beams. This information along with the n slash m height ratio is normally supplied by the fixture manufacturer of each luminaire direct luminaires a concentrated, direct spread luminaires spread the lot over regional area and semi direct have indirect luminaires. Direct indirect, General, diffused and semi direct are all options when selecting luminaires. Indirect can be classified as these types are based on the percentage of light emitted above and below the horizontal surface the actual distribution of a specific cific luminary is determined by the lamp used and the fixture design for which it is mounted. Consult the manufacturer off for this kind of information and best selection of your application. The M slash m h As stated earlier guidelines specific ratios of maximum luminary spacings to mounting height in order to achieve an acceptable uniformity of illumination of a space.

For most luminaires the mounting height is measured from the luminaries and the mountain part is measured from the working plane or the assumed working plane. For semi indirect and indirect lighting systems. That system of the ceiling plane as a reflector, and the mounting hot is measured from the ceiling to the working plane. For increases in all brightness and general higher levels of arousal emanating a space by placing the luminaries away from the wall at a one to three ratio spacing luminaries farther apart, that is the S slash m height ratio suggests results of uneven illumination or along a horizontal planning for uniform level of illumination, which is desired usually spacing brackets s should be equal to the calculation of s slash m height ratio by the M h ratio. Direct lighting of the work of visual past client or indirect lighting, he sees the ceiling plane as a reflector.

Room index as ri the way in which the dimensions of the interior and the mounting height of the luminaire effect the utilization is rather complex, but it has been found that there may be allowable by classifying installations by their room index. This is found mathematically according to the following formula. Room index as ri equals the length by width of a room divided by the myth the mounting height times by the length by width of the room. Please refer to this equation where L is the room length, W is the room width and m h as the mounting height above the working plane, whether that be the floor or a working desk. An example of this can be seen as the following a room with a length of 28 meters long by 12 meters wide with a mounting height of 2.5 meters above the floor in this circumstance is 28 by 12 divided by 2.5 times by 28 by 12, which equals 40.

So, let me rephrase 28 by 12 divided by 2.5 times by 40 gives you an equation sum of 336 divided by 100 and it gives you a 3.36 ratio or a 3.0 room index. utilization factor is known or equated as u f when you see it written on something. When planning and interior lighting scheme, it is necessary to calculate the number of light fittings or luminaires required to achieve a specified maintenance illuminance level on a working plane. Only a proportion of the light emitted by the lamps in the luminaires will eventually reach the working plane. In account for this, there must therefore be taken into all considerations of calculations made. The following factors affect the quantity of light that will reach the working plane.

This is known as the utilization factor, light distribution, interior decoration, size and shape of the interior. Again, the mounting height of the luminary selected