Question

maximum protection from on - the - job noise is provided by _____. *
earplugs
ear muffs
earplugs used with ear muffs

when a respirator is required, a personal monitoring device is usually also required to _____.
monitoring breathing rate
measure the concentration of hazardous chemicals
ensure respirator works
check oxygen level in the space

Explanation:

For the first question, earplugs with earmuffs offer the most comprehensive noise - blocking. For the second question, when a respirator is needed, a personal monitoring device is usually for measuring the concentration of hazardous chemicals to ensure the environment is safe.

Answer:

1. C. earplugs used with earmuffs
2. B. measure the concentration of hazardous chemicals