Table 2.
Work exposure durations by subject-interval
| Trade | n subject-intervals | Subject-interval duration (years) |
Subject-interval noisy work hours |
Noisy work hours per year |
% Intervals with construction work | ||||
| Mean | SD | Mean | SD | Rank | Mean | SD | |||
| Construction workers | 1062 | 1.4 | 1.1 | 2627 | 2465 | — | 1747 | 757 | 94.9 |
| Carpenter | 252 | 1.5 | 1.3 | 2614 | 2524 | 8 | 1612 | 800 | 89.7 |
| Cement mason | 98 | 1.6 | 1.5 | 2762 | 3104 | 7 | 1637 | 782 | 94.9 |
| Electrician | 76 | 1.4 | 1.1 | 2309 | 1660 | 5 | 1720 | 702 | 96.1 |
| Insulation worker | 60 | 1.3 | 0.9 | 2490 | 1988 | 4 | 1837 | 630 | 98.3 |
| Ironworker | 180 | 1.3 | 0.9 | 2469 | 2090 | 3 | 1841 | 746 | 93.9 |
| Masonry worker | 239 | 1.4 | 0.9 | 2531 | 2466 | 6 | 1696 | 790 | 92.5 |
| Operating engineer | 68 | 1.8 | 1.1 | 3647 | 3416 | 1 | 1992 | 882 | 100 |
| Sheet metal worker | 89 | 1.3 | 1.1 | 2677 | 2062 | 2 | 1974 | 332 | 98.9 |
| Controls | 236 | 1.3 | 0.9 | 0 | 0 | — | 0 | — | 0 |