Industrial lighting / Commonwealth of Australia Department of Labour and National Service, Industrial Welfare Division.

Date:
1945
Catalogue details

Licence: In copyright

Credit: Industrial lighting / Commonwealth of Australia Department of Labour and National Service, Industrial Welfare Division. Source: Wellcome Collection.

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    C. HIGH QUALITY OF FLUORESCENT LIGHTING Australian-made fluorescent lamps produce ight that is a close approach to daylight. The standard wartime colour of light is 3500°K. A wide range of other colours is standard in U.S.A., but is not available in Australia at pre- sent. Some distortion of colours occurs, but it is so slight as to be unimportant except as it — foodstuffs. Tubular fluorescent lamps produce high- quality illumination because the comparatively low brightness per square inch of tube reduces direct and reflected glare to a minimum, while the long, tubular source directs light towards any object at many «angles, thus softening around curved surfaces and beneath obstructions. D. Hot- AND CoLD-CATHODE COMPARED of the two types of fluorescent lamps should be used in each of the numerous industrial applica- tions, the following general summary of the type should aid in selection. Buyers should carefully sort out the contentious matter of relative costs. : 1. Hot-Cathode Advantages Higher Jumens output per watt. | Standard lamp replacements available from many merchants. Higher lumens output per foot. Flicker (stroboscopic) effects almost’ elim- inated by twin-lamp ballasts. Page 34 Shorter lamp life (less than half of that of cold-cathode). Lamp life further reduced by frequent switch- ing on and off. | More components in auxiliary equipment, — and usually heavier maintenance. 2. Cold-Cathode Advantages Long life (about twice that of hot-cathode) . Tube life not reduced by frequent starting. Simple auxiliary equipment. Disadvantages Lower lumens output per watt and per foot. Slight flicker (stroboscopic) effect. Tube replacements probably have to be ob- tained from original supplier. Tubes operate at high voltage and need rather 7 Generally, cold-cathode fluorescent lighting localised general lighting, and it is particularly effective when used in long runs above benches or machines. The greater light-output of hot-cathode fluore- | scent tubes (four 40-watt tubes and four 100- watt tubes, respectively, approach the light- outputs of 500-watt and 1000-watt incandes- — cent lamps) as compared with the cold-cathode variety, is such that they can be used in a reasonable size of fitting to produce a light- output suitable for general lighting or localised fluorescent lamps, i.e., 20 or 40 watt, are useful for supplementary lighting of tasks.