From: Retrospective exposure assessment to airborne asbestos among power industry workers
 | Power generation | Power distribution | Gas supply |
---|---|---|---|
N a | 5622 (65%) | 2498 (29%) | 512 (6%) |
Mean age b | 55 (12) | 45 (12) | 54 (11) |
Period of employment c | 20 (12) | 22 (9) | 25 (9) |
Asbestos exposure c | 20 (10) | 13 (8) | 15 (9) |