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SINGAPORE & THE FEDERATION OF MALAYA
There are many methods for eliminating direct glare, one being to shield the tube from view by means of reflectors. A trough type reflector is used which cuts off the light above a certain angle and re-directs it downwards, The reflectors may be either of metal or of some translucent materials of high reflection. Another methed is to enclose the tube by means of a diffusing medium so that the light from the tube is spread over a large area with consequent reduction in surface brightness. The adoption of this second method of brightness control necessitates the use of a material which provides good diffusion with maximum transmission, a popular solution being to employ a clear "Perspex" which has narrow ribs formed on one surface, the ribs break up and scatter the light whilst the loss in light transmission is in the region of 10% only.
A particular virtue of the enclosed type of fitting is that the large area of the source and the diffused quality of the lighting minimises any tendency to reflected glare-this is of particular importance in the office where specular reflection off glossy paper and the polished parts of typewriters etc. can be a frequent cause of complaints as to eye-strain and headaches.
In designing for comfort the whole visual environment should be taken into consideration, the decorative and furnish- ing scheme will have a great influence on the result of the lighting and should be planned in relationship to the required illumination values. Wide contrasts in brightness can
be avoided by ensuring that adjacent surfaces have similar reflection factors: the lighter the colour of walls, ceiling, furniture, etc., the higher can be the illumination without discomfort,
COLOUR OF FLUORESCENT LIGHT.
One of the great advantages of the fluorescent tube is the possibility of obtaining a range of whitish lights, varying from the cold bluish-white, to the soft warm "Peach". At present there are three shades of white available all of equal efficiency and catering for the majority of requirements as regards spectral quality.
The most popular tube for Industrial and Commercial use is the 4500°K "Daylight" (equivalent to the American 4500°K "White"). The light from this tube blends extremely well with natural daylight and combines a pleasant general appearance with a remarkably correct colour rendering of materials. The general impression is that of a crisp clear light suitable for factory and cffice and in stores and shops where it is important to see materials in their natural colours; where fabrics, dresses and so on are sold, this is particularly necessary.
"Warm White" (similar to the American "Soft White") has a pinkish hue and is used for offices which have no natural daylight.
"North Light" which has a colour temperature of 6500*K gives a cold blueish light similar to the American "Daylight". It was specially designed for applications where accurate colour discrimination is of importance, such as colour printing, artists' studios and commercial colour matching. It is normally used for localised lighting only.
The colour which is called "Peach" (similar to the American "Warmtone") is the result of intensive research into the effect of fluorescent lighting on materials, food and human complexions. It has considerable warmth and is generally desirable where a warm, intimate atmosphere is of primary importance. In Great Britain, the introduction of the "Peach" tube has opened up new fields in the application of fluorescent lighting to homes, restaurants, clubs and other
Small general office lighted by means of translucent opal trough reflectors.
interiors where people are at rest and wish to have a cosy atmosphere which a warm coloured light provides. Of great importance is the fact that the soft light from "Peach" tubes is flattering to the complexion and has none of the cruelties of the bluish industrial colour which throws every wrinkle and skin blemish into relief with such devastating clearness.
PLANNED LIGHTING.
The complexity of modern light sources and equipment and the mass of data which has become available as regards lighting requirements makes specialized planning of lighting necessary if the results are to be satisfactory and economically justifiable.
The lighting requirements of the small office, workshop, small store etc. are fairly straight forward but where the seeing task is severe, such as in schools, or complex such as in textile mills, printing works and the like, or when the lighting system has to be superimposed upon a building of architectural merit, the advice of a lighting engineer should be sought. Not only has he the technical knowledge of light and lighting, but he has also the background of past experience as to what form of lighting might be suitable or unsuitable for any given interior. The relighting of existing buildings must always be somewhat of a compromise by virtue of the limitations imposed by structural and decorative details, but in new builings, there is no need for such compromise provided that the light- ing is decided at an early stage in the building design. Provision can be made for the wiring and fixing of particular types of fittings or for the construction of cornices and other features for concealed lighting systems, consideration can be given to the fact that ventilation duets, fans, water sprinkler systems and other services may have to be accommodated above or on the surface of ceilings, and if the lighting is planned along with such services, there will be no mutual obstruction.
In planning the lighting, the architect should have the service of the lighting engineer from the outset so that the fullest advantage can be taken of modern lighting technique and equipment. Mutual collaboration ensures that the lighting will become an integral part of the building and will be not only aesthetically pleasing but functionally correct.
The main book room of "Westminster City Council Central Library." Note the uniform vertical illumination and absence of glare or
shadow.
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