Propane Certification Propane Certification Emergency Procedures 2 — Questions and Answers
Question 1: Which type of fire extinguisher is recommended for most propane-related fires?
- Dry chemical (BC or ABC rated) (Correct answer)
- Water extinguisher
- CO2 extinguisher only
- Foam extinguisher
Correct answer: Dry chemical (BC or ABC rated)
Dry chemical extinguishers rated BC or ABC are recommended for propane fires because they interrupt the chemical chain reaction of combustion effectively.
Question 2: After a propane leak has been stopped and the area ventilated, what must be done before re-lighting any appliances?
- A leak test must be performed on the entire system (Correct answer)
- The supplier must be notified and approve restart
- The relief valve must be manually reset
- The container must be replaced with a new one
Correct answer: A leak test must be performed on the entire system
After any leak event, a complete leak test using approved methods must confirm the system is leak-free before appliances are returned to service.
Question 3: What chemical is added to propane to give it a distinctive odor for leak detection?
- Ethyl mercaptan (ethanethiol) (Correct answer)
- Sulfur dioxide
- Hydrogen sulfide
- Chlorine gas
Correct answer: Ethyl mercaptan (ethanethiol)
Ethyl mercaptan (ethanethiol) is the most common odorant added to propane, producing the characteristic rotten egg or skunk-like smell.
Question 4: A customer reports that they smell propane but the odorant seems fainter than usual. This could indicate:
- Odor fade due to oxidation or absorption in new containers or piping (Correct answer)
- The propane supplier changed the odorant formula
- The customer's sense of smell is impaired only
- The container pressure is too low
Correct answer: Odor fade due to oxidation or absorption in new containers or piping
Odor fade occurs when ethyl mercaptan is absorbed by rust in new tanks or oxidized in the presence of air and moisture, reducing detectable odor levels.
Question 5: When is it acceptable to use an open flame to check for a propane leak?
- Never — always use an approved leak detection solution or electronic detector (Correct answer)
- Only outdoors with good wind
- Only on low-pressure systems below 0.5 psi
- Only when the leak is very small
Correct answer: Never — always use an approved leak detection solution or electronic detector
Open flame leak detection is never acceptable because it can ignite the propane being tested, causing serious injury or death.
Question 6: What is the lower explosive limit (LEL) of propane in air, below which ignition cannot occur?
- 2.1% (Correct answer)
- 4.0%
- 1.0%
- 5.5%
Correct answer: 2.1%
Propane's lower explosive limit is 2.1% by volume in air; concentrations below this level are too lean to ignite.
Propane Certification Propane Certification Emergency Procedures 2
Which type of fire extinguisher is recommended for most propane-related fires?