Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 216
umination in a space of18 days continuous use varies from18*5 per cent, to 45 pei cent., dependingon the conditions of service. The estimation of the mean horizontalillumination by the flux method is inthis case particularly easy. The sym-metrical arrangement of the points, andthe flat plane of… … IV. —Railway Booking Hall lighted by tungsten lamps in prismatic Ulass reflectors. Observations were taken over thecentral area of the room some days afterthe installation was put in, and readingsof about 15 foot-candles were obtained. Inthis case also, reflection from the wallsdoes not appear to…
Lighting
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