PROPANE ANSWERS WELL
ELABORATED GRADED A+ ||UPDATED
2026/2027
Question 1
What is propane?
Answer: A fossil fuel found mixed with natural gas and petroleum deposits
in rock formations deep underground.
Question 2
What is the expansion ratio of liquid propane to vapor?
Answer: 270:1
(1 gallon of liquid propane expands into 270 gallons of vapor gas at standard
atmospheric pressure).
Question 3
What is the vapor density of propane, and what does this mean relative to air?
Answer: 1.56, which makes propane heavier than air (air = 1.0).
Question 4
Because propane vapor is heavier than air, how does it disburse when leaked?
Answer: It seeks low areas (basements, pits, drains) and accumulates there
until it dissipates or encounters an ignition source.
Propane -ANSWER ✔✔LEL 2.3 UEL 9.5
1 gallon of propane weighs -ANSWER ✔✔4.23 lbs
Propane ignition temperature -ANSWER ✔✔920 degrees Fahrenheit and 1120
degrees Fahrenheit
, Natural form propane -ANSWER ✔✔is colorless and odorless
Mercaptan is added to propane for smell -ANSWER ✔✔20% below lower
explosive limit. 1 pound per 10,000 gallons, equates to 1 part per billion.
Propane is in a liquid state when contained and stored -ANSWER ✔✔Specific
gravity of propane .504 versus water 1.0 which makes it lighter than water.
Propane when released into the atmosphere -ANSWER ✔✔will change from liquid
to vapor, during a release cloud that is visible is not product but condensed
moisture in air that is cooled by leaking product.
Apparatus placement propane emergency -ANSWER ✔✔Position prior to and
upwind of the hazard area if at all possible & determine most efficient water
supply.
Other units shall stage upwind and prior to the affected area and await an
assignment from the engine company or Incident Commander.
Outside Propane Leaks -ANSWER ✔✔1- Safe perimeter shall be established using
detection/monitoring equipment- these must be intrinsically safe and bump tested
prior to entering hot zone.
2- Evacuation decisions should be based on monitoring data, wind direction,
terrain, and size of leak.
3- Check around sewer manholes and under ground vaults.
4- Imperative to check surrounding basements, and buildings in area for
accumulating gas
Propane can travel long distances underground before escaping.
ELABORATED GRADED A+ ||UPDATED
2026/2027
Question 1
What is propane?
Answer: A fossil fuel found mixed with natural gas and petroleum deposits
in rock formations deep underground.
Question 2
What is the expansion ratio of liquid propane to vapor?
Answer: 270:1
(1 gallon of liquid propane expands into 270 gallons of vapor gas at standard
atmospheric pressure).
Question 3
What is the vapor density of propane, and what does this mean relative to air?
Answer: 1.56, which makes propane heavier than air (air = 1.0).
Question 4
Because propane vapor is heavier than air, how does it disburse when leaked?
Answer: It seeks low areas (basements, pits, drains) and accumulates there
until it dissipates or encounters an ignition source.
Propane -ANSWER ✔✔LEL 2.3 UEL 9.5
1 gallon of propane weighs -ANSWER ✔✔4.23 lbs
Propane ignition temperature -ANSWER ✔✔920 degrees Fahrenheit and 1120
degrees Fahrenheit
, Natural form propane -ANSWER ✔✔is colorless and odorless
Mercaptan is added to propane for smell -ANSWER ✔✔20% below lower
explosive limit. 1 pound per 10,000 gallons, equates to 1 part per billion.
Propane is in a liquid state when contained and stored -ANSWER ✔✔Specific
gravity of propane .504 versus water 1.0 which makes it lighter than water.
Propane when released into the atmosphere -ANSWER ✔✔will change from liquid
to vapor, during a release cloud that is visible is not product but condensed
moisture in air that is cooled by leaking product.
Apparatus placement propane emergency -ANSWER ✔✔Position prior to and
upwind of the hazard area if at all possible & determine most efficient water
supply.
Other units shall stage upwind and prior to the affected area and await an
assignment from the engine company or Incident Commander.
Outside Propane Leaks -ANSWER ✔✔1- Safe perimeter shall be established using
detection/monitoring equipment- these must be intrinsically safe and bump tested
prior to entering hot zone.
2- Evacuation decisions should be based on monitoring data, wind direction,
terrain, and size of leak.
3- Check around sewer manholes and under ground vaults.
4- Imperative to check surrounding basements, and buildings in area for
accumulating gas
Propane can travel long distances underground before escaping.