Noise, Hearing Protection, Radiation and Lasers practice questions for the CHST exam

A worker's day includes several periods of noise at different constant levels. The safety technician computes the equivalent noise exposure factor (Fe) using the sum of T/L for each period and gets Fe = 1.20. How should this result be interpreted?

1. A.The exposure is within permissible limits as long as no single period exceeded its own limit
2. B.The exposure is within permissible limits because Fe is below 2
3. C.The exposure exceeds permissible levels because Fe is greater than unity
4. D.The result is invalid because each noise period must be evaluated individually, not combined

A sound level meter (A-scale, slow response) shows that employees running a stationary concrete crusher are exposed above the Table D-2 limits. The superintendent proposes to issue earplugs to everyone at once and take no other action. A sound-dampening enclosure for the crusher and a crew rotation schedule are both feasible and inexpensive. Is the superintendent's plan consistent with the standard?

1. A.No, because feasible administrative or engineering controls must be used first, and PPE is required only if those controls fail to bring levels within the table
2. B.Yes, because hearing protection is the fastest way to bring exposure within the table, so the standard lets the employer choose it first
3. C.Yes, as long as a warning sign is posted at the crusher, since signs substitute for controls when PPE is issued
4. D.No, because the standard requires all work near the crusher to stop until levels fall below the table without any PPE