Document 2NadRjoQ1Nd4vDkdw57KzQVq7
46--Safety Engineering Tables
TABLE 46-F MAXIMUM BRIGHTNESS RATIOS
Environmental Clarification
A BC
Between task and adiacent darker surroundings Between tasks and adiacent lighter surroundings
Between tasks and more remote darker surfaces Between tasks and more remote lighter surfaces Between luminaires (or windows, skylights, etc )
and surfaces adiacent to them Anywhere within normal field of view
3 to 1 1 to 3 10 to 1 1 to 10
20 to 1 40 to 1
3 to 1 1 to 3 20 to 1 1 to 20
*
5 to 1 1 to 5
*
* *
'Brightness Ratio control not practical
A-tntenor Areas where reflectances of entire space can be controlled in line with recommendations for optimum see ing conditions
B-Areas where reflectances of immediate work area can be controlled but control of remote surroundings is limited
C-Areas (indoor and outdoor) where it is completely impractical to control reflectances and difficult to alter environ mental conditions
Note From the normal view point bnghtness ratios of areas of appreciable size in industnal areas should not exceed those in the above table
From American National Standard All 1--1973, Practice for Industrial Lighting, Illuminating Engineering Society
TABLE 46-G LEVELS OF ILLUMINATION RECOMMENDED FOR SAMPLE OCCUPATIONAL TASKS
Area
Foot-candles
Area
Foot-candles
Assembly--rough, easy seeing Assembly--medium Building construction--general Electrical equipment, testing Elevators Garages--repair areas Garages--traffic areas Inspection, ordinary Inspection, highly difficult Loading platforms Machine shops--medium work
30 Materials--loading, trucking
20
100 Offices--general areas*
100
10 rafting rooms--detailed*
200
100 Corndors
20
20 Paint dipping, spraying
50
100
Service spaces--wash rooms, etc
30
20 Sheet metal--presses, shears
50
50 Storage rooms--inactive
5
200 Storage rooms--active, medium
20
20 Welding--general
50
100 Woodworking--rough sawing
30
From A132 1--1973, Office Lighting, published by the Illuminating Engineering Society Others from ANSI All 1-- 1973 See explanation on page 1449
1456