CMC - Certified Marine Chemist Vessel-Specific Hazards Questions and Answers 1

Question 1

A Marine Chemist is called to certify a cargo hold on a bulk carrier that last transported wood pellets.
What is the PRIMARY atmospheric hazard the chemist must test for prior to issuing a 'Safe for Entry' certificate?

Accepted Answer

Carbon monoxide and oxygen deficiency

Answer

Oxygen enrichment from cargo decomposition

Answer

Flammable methane gas release

Answer

Hydrogen sulfide from residual moisture

Question 2

When inspecting a double-hulled LNG (Liquefied Natural Gas) carrier for hot work on the outer hull, which of the following is a unique hazard specific to this type of vessel that a Marine Chemist must consider?

Accepted Answer

Extreme cold temperatures from the cargo causing steel embrittlement.

Answer

Presence of flammable vapors in the ballast tanks due to cargo leakage.

Answer

The potential for pyrophoric iron sulfide deposits in the void spaces.

Answer

High concentrations of inert gas in the cargo tanks.

Question 3

A Marine Chemist is preparing to certify a space on a chemical tanker that recently carried Benzene. According to common occupational exposure limits, which atmospheric concentration is most critical to monitor for worker safety?

Accepted Answer

Benzene vapor above 1 ppm

Answer

Oxygen level below 19.5%

Answer

Hydrogen Sulfide (H2S) above 5 ppm

Answer

Lower Explosive Limit (LEL) above 10%

Question 4

On a Roll-on/Roll-off (Ro-Ro) vessel, which of the following represents a significant fire hazard that is less common on a traditional bulk carrier or tanker?

Accepted Answer

Electrical faults and fuel leaks from vehicles being transported.

Answer

Spontaneous combustion of coal cargo.

Answer

Static electricity discharge during cargo operations.

Answer

Flammable vapor buildup in cargo holds from liquid cargo.

Question 5

A Marine Chemist is called to a container ship to evaluate a hold where a container has reportedly leaked an unknown substance. The primary hazard in this scenario, compared to a tanker with a known cargo, is the:

Accepted Answer

Difficulty in determining the specific chemical properties and required PPE.

Answer

Lack of a fixed fire suppression system.

Answer

Increased risk of oxygen deficiency due to the large, open space.

Answer

High probability of flammable vapors exceeding 100% of the LEL.

Question 6

When certifying a pump room on an oil tanker for hot work, a Marine Chemist must be particularly vigilant for which combination of hazards?

Accepted Answer

Flammable hydrocarbon vapors and potential ignition sources.

Answer

Oxygen enrichment and high-pressure hydraulic leaks.

Answer

Asphyxiation from inert gas and static electricity.

Answer

Corrosive chemical residue and tripping hazards.