lighting requirement in shelf and rack storage system (Ontario building code)

[sunyaer]

This is a question about lighting requirement in shelf and rack storage system (Ontario building code). Which of the following combinations of readings recorded in various portions of the deck surface area conforms to the normal lighting requirements of the building code? (It seems B is the answer, but the 0 lux over 20 m^2 doesn't seem correct.)



OBC requirements:

 

[tmurray]

I'm not understanding the answers. Lux is a composite of lighting and area, so saying 10 lux over 100sq.m. doesn't make much sense.

10 lux = 10 lumen/square meter.

You can't have a number of lux over any area other than a single square meter.

The way it works in practice is that the code sets a number of lux that must be met. The light fixture will have the number of lumens it emits. In a standard grid lighting system, you just divide the total lumens by the total area to get the lux.

 

[Paul Sweet]

I think that A is a uniform light intensity of 10 lux over the entire 100 M^2 area, and the others are varying light levels in different parts of the whole area.

B is the only one which is over 50 when you multiply the lux by partial area, sum them up, then divide by the total area. In practice I doubt there would be any area with 0 lux, although there might be just 1 or 2 lux at the back of deep shelves.