Safety Procedures Flashcards

Per OSHA's permit-required confined space standard, an atmosphere is considered hazardous when flammable vapor exceeds what percentage of the LEL?

Answer: 10%

29 CFR 1910.146 defines flammable gas or vapor above 10% of the LEL as a hazardous atmosphere.

What is the acceptable oxygen range for confined space entry under OSHA?

Answer: 19.5% to 23.5%

Below 19.5% is oxygen-deficient and above 23.5% is oxygen-enriched.

In what order should a multi-gas meter test a confined space atmosphere?

Answer: Oxygen, flammables, toxics

Oxygen is tested first because many combustible sensors need adequate oxygen to read accurately.

What role must the confined space attendant NOT perform?

Answer: Enter the space to perform rescue

Attendants must remain outside and must not enter to attempt rescue unless relieved by another attendant.

For vertical entry into a permit space deeper than 5 feet, what is required?

Answer: A mechanical retrieval device

OSHA requires a mechanical retrieval device for vertical entries over 5 feet deep.

Why should a gas detector be bump-tested before each day's use?

Answer: To verify sensors respond and alarms activate

A bump test confirms the sensors and alarms respond to a known gas concentration.

During spray application inside a tank, what is the common practice for keeping solvent vapor levels safe?

Answer: Ventilate to stay at or below 10% LEL

Continuous ventilation that holds vapors at or below 10% LEL greatly reduces fire and explosion risk.