Light 4

Question 0

Glare makes

Answer 0

seeing difficult and occurs when some areas are much brighter or darker than others.

Question 1

The chief requirements for proper lighting are

Answer 1

sufficient light, proper placement of fixtures to prevent shadows, and elimination of both direct and reflected glare.

Question 2

The amount of lighting needed in a room depends on

Answer 2

the room’s use. Stronger light is needed for study and close work than for conversation or watching television.

Question 3

Lighting engineers calculate the level of lighting in units called

Answer 3

lumens.

Question 4

for areas designed for writing and studying, they recommend around

Answer 4

70 lumens per square foot (753 lumens per square meter), whereas for general lighting less than one-half that amount is needed.

Question 5

A 100-watt incandescent bulb provides approximately

Answer 5

1,700 lumens

Question 6

A 30-watt fluorescent tube provides

Answer 6

up to 1,800 lumens.

Question 7

For rooms where detailed work (such as drafting) is done, lighting engineers recommend up to

Answer 7

200 lumens per square foot (2,153 lumens per square meter).

Question 8

To help avoid glare, engineers recommend room walls with

Answer 8

a light, dull finish.

Question 9

In general, ceilings should reflect

Answer 9

75 per cent of the light they receive; upper walls, more than 50 per cent; and lower walls, more than 33 per cent