Frequently Asked Questions

Below you can find some of our most frequently asked questions about propane and propane tanks.

Question: What is propane?

Answer: Wikipedia defines propane as "a three-carbon alkane with the molecular formula C3H8, normally a gas, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as a fuel for engines, oxy-gas torches, barbecues, portable stoves, and residential central heating."

Question: Why does propane smell?

Answer: In its natural state, propane is an odorless gas. As a safety precaution, a chemical called Ethyl Mercaptan is added so that any presence of propane may be easily detected. The concentration level of ethyl mercaptan that is added to propane is not harmful.

Question: Is propane dangerous to the environment?

Answer: No, propane is an approved, clean fuel listed in the 1990 Clean Air Act and the Energy Policy Act of 1992. Propane is one of the cleanest burning of all fossil fuels. Tests conducted by the U.S. Environmental Protection Agency show that propane-fueled vehicles produce 30% to 90% less carbon monoxide and about 50% fewer toxins and other smog-producing emissions than gasoline engines. Propane also is non-toxic, so it's not harmful to soil or water. In the event of a leak, propane will dissipate into a vapor, leaving no lasting effect on the surrounding environment

Question: How much can my propane tank hold?

Answer: Propane tanks are most commonly referred to by their water capacity volume, and propane tanks are normally filled to 80% of its water capacity. For example, a 120-gallon tank will hold approximately 100 gallons of propane when completely full. Since propane is stored in a liquid state under pressure, it needs room to expand into a vapor. This extra "room" that is in the tank allows for that expansion. Depending on the ambient temperature outside, propane may expand more or less.

Propane Tank Capacities (assuming 80% of tank water capacity)

20lb Propane Tank ~ 3.5 Propane Gallons

100lb Propane Tank ~ 24 Propane Gallons

420lb Propane Tank (120 Gallon WC) - 100 Propane Gallons

500 Gallon Propane Tank (500 Gallon WC) - 400 Propane Gallons

1,000 Gallon Propane Tank (1000 Gallon WC) - 800 Propane Gallons

Question: How is propane weighed or measured?

Answer: Propane can be measured in a few manners. The most common way is by gallons. It can also be measured by pounds (one gallon = 4.2lbs). When measured in gallons, a meter at the pump is used to determine the amount of propane that has been filled into a tank. When measured in pounds, the tare (empty starting) weight of the tank must be known first. After this weight is taken into account, the tank is then filled to capacity with the correct volume. (i.e. A BBQ tank is commonly referred to as a 20lb tank. This is because these tanks hold 20lbs or approximately five gallons of propane).

Question: What is a BTU?

Answer: The British thermal unit (BTU ) is a unit of energy used in the power, steam generation, heating and air conditioning industries. For propane use, one gallon of propane will burn 91,690 BTUs. Most household log fireplace sets will burn approximately 30,000 BTUs per hour. This relates to roughly three hours of continuous use per gallon, though the pilot light must also be taken into account.

Question: What is GAS Check?

Answer: GAS Check® is an inspection program developed by the National Propane Gas Association (NPGA) and the Propane Education & Research Council (PERC) and funded by PERC that provides guidelines for technicians on how to perform two different types of residential safety inspections:

Question: How Much Does Propane Cost?

Answer: Propane prices can vary (sometimes) significantly between propane suppliers.  So why the big difference?  Well, for some propane companies, that's just their business model.  Propane in the United States is supplied to most propane distributors from mostly the same refineries.  This is partially responsible for the cost difference - transportation to the supplier.

Other factors, such as pipeline tariffs, supply/demand from the refinery, availability, and a variety of other conditions that affect the market rates.

GasTec's propane prices are based on market rates and trends.  As the market moves, your propane price will move too - this means down when the market moves down!

Question: Does Propane go bad?

Answer: Unlike many other types of fuels that go bad after some time, or need stabilizers to last periods of time, Propane is there until you use it.  Due to the nature of the storage and makeup, there is no shelf life of propane.  One thing to note, that while the propane is good practically indefinitely, it is worth mentioning that the containing must remain in good condition (container and valves).