CNG Properties and Safety 2

Question 1

What is the primary component of compressed natural gas (CNG)?

Accepted Answer

Methane

Answer

CNG is composed primarily of methane (CH4), typically making up 90% or more of its composition.

Question 2

CNG is stored in vehicle cylinders at approximately what pressure?

Accepted Answer

3,600 psi

Answer

CNG is typically stored in high-pressure cylinders at around 3,600 psi (248 bar) in vehicles.

Question 3

What color are CNG fuel lines typically required to be for identification purposes?

Accepted Answer

Orange

Answer

CNG fuel lines are typically color-coded orange to distinguish them from other vehicle fluid lines.

Question 4

Which property makes CNG safer than gasoline in terms of spill behavior?

Accepted Answer

It dissipates into the atmosphere rather than pooling

Answer

Being lighter than air, CNG disperses upward and dissipates into the atmosphere rather than pooling on the ground like liquid fuels.

Question 5

What is the Lower Flammability Limit (LFL) of methane in air?

Accepted Answer

5%

Answer

Methane's Lower Flammability Limit is approximately 5% by volume in air, below which ignition cannot occur.

(CNG) Compressed Natural Gas Practice Test