Linear tungsten-halogen lamps must be used horizontally, otherwise the halogen vapour will concentrate at its lower end, which results in rapid blackening of the tube and a reduced operating life. Both are particularly useful for display, floodlighting and spotlighting.
Tungsten-halogen lamps must be carefully handled while being fitted. If the outside surface of the quartz tube or bulb is touched with dirty or greasy hands premature failure can occur due to fine surface cracks in the glass. Handle the tube by its ends only, or use a paper sleeve over the lamp during fitting. If accidentally handled, the lamp glass may be cleaned with a spirit solvent, carbon tetrachloride or trichloroethylene. (Refer Figure 22.2)
Figure 22.2 - Linear Tungsten-Halogen Lamp - Double-ended
