CMC Confined Space Entry Requirements 2

Question 1

Under OSHA 29 CFR 1915, what is the minimum oxygen concentration considered acceptable for entry into a confined space aboard a vessel?

Accepted Answer

19.5% by volume

Answer

16.5% by volume

Answer

21.0% by volume

Answer

23.5% by volume

Question 2

Which document authorizes workers to enter a permit-required confined space on a vessel?

Accepted Answer

Entry permit signed by the marine chemist or competent person

Answer

Hot work permit

Answer

Safety data sheet

Answer

Vessel safety plan

Question 3

What action must be taken before testing the atmosphere of a tank that previously contained flammable cargo?

Accepted Answer

Ensure the space is gas-free of cargo vapors before entering

Answer

Ventilate for at least 30 minutes

Answer

Purge with inert gas

Answer

Apply fire-retardant coating

Question 4

What is the maximum permissible concentration of carbon monoxide (CO) for safe entry into a vessel's confined space per OSHA 1915?

Accepted Answer

50 ppm

Answer

25 ppm

Answer

35 ppm

Answer

100 ppm

Question 5

When a marine chemist labels a space 'Safe for Workers,' what does this designation specifically mean?

Accepted Answer

The atmosphere is safe for entry without respiratory protection

Answer

The space is safe for hot work operations

Answer

The space is inert and worker entry is prohibited

Answer

Fire suppression systems have been deactivated

Question 6

Which type of ventilation is preferred for confined spaces with heavy vapors that settle near the bottom?

Accepted Answer

Bottom-exhaust mechanical ventilation

Answer

Top-exhaust only ventilation

Answer

Natural draft ventilation

Answer

Forced air supply at the top

Question 7

If continuous atmospheric monitoring detects a flammable vapor reading of 12% LEL during entry operations, what must occur?

Accepted Answer

Immediately evacuate all personnel from the space

Answer

Increase ventilation and continue work

Answer

Switch to supplied-air respirators and continue

Answer

Notify the shipowner and resume after 15 minutes