What is Propane?

Propane is a three-carbon alkane with the molecular formula C3H8. It is a gas at standard temperature and pressure, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as a fuel. Propane is one of a group of liquefied petroleum gases (LP gases) including butane, propylene, butadiene, butylene, isobutylene, and mixtures thereof.

Propane is produced as a by-product of two other processes, natural gas processing and petroleum refining. The processing of natural gas involves removal of butane, propane, and large amounts of ethane from the raw gas, in order to prevent condensation of these volatiles in natural gas pipelines. Additionally, oil refineries produce some propane as a by-product of cracking petroleum into gasoline or heating oil. Propane was discovered by the French chemist Marcellin Berthelot in 1857.”

- (Wikipedia, 2019, Propane)

What Does Propane Smell Like?

Like Natural gas, propane also comes with a very robust and quite disagreeable smell like rotten eggs or even a dead animal. Also similar to natural gas, the manufacturers of propane add this unpleasant smell on purposed in order to notify customers when propane may be unexpectedly leaking.

Propane Smell Education?

It is absolutely essential that you teach everyone in your home, especially your kids or any elderly individuals, what propane smells like. If you do not feel comfortable or knowledgeable enough to do this, then it is recommended that you seek help from a propane company or distributor for a demonstration. Everyone in your home needs to show that they understand and can identify the smell of natural gas and propane to ensure their ability to appropriately react in the event of a gas leak.

Test Your Sense of Smell

Believe it or not, some people may not be able to smell propane in the event that it is leaking. The can occur for a number of reasons listed below.

  • Allergies, cold, or flu can cause sinus congestion which blocks the sense of smell.
  • Extended use of drugs, tobacco, or alcohol may damage and diminish one’s sense of smell.
  • If someone is cooking, grilling, smoking, spraying perfume, or releasing any other kind of strong smell, this can block you from smelling propane.
  • With age, people lose their sense of smell.
  • When exposed to propane for an extended period of time, some people can simply get used to the smell of propane and, after a while, can no longer smell it.
  • If you are asleep, the odor of propane, although strong, may not be enough to awaken you.
  • The propane leak in your house may be in an area which is not near you (i.e. garage, downstairs, upstairs, back porch, etc.)
  • Odor Loss may occur. See below for more details on Odor Loss.

Definition of Propane Odor Loss

Propane odor loss is when propane actually loses the distinct “rotten egg” or “dead animal” smell that was mentioned above. Remember that propane does not originally contain any smell until the manufacturer adds that strong, and unpleasant smell to the propane during its production. There are a number of a factors which can trigger propane to lose its added distinctive odor. Please read on.

Causes of Odor Loss

  • Propane tanks sometimes have air, water, or rust in them which may diminish the odor concentration.
  • If propane leaks into the earth or underground, the earth may filter out the mercaptan from the propane which can lead to a reduction in the strength of the smell of the propane.
  • The mercaptan can be absorbed into the lining of certain gas piping/tubing and possibly other materials, thus taking out the distinctive smell from propane.
  • Respond instantly to the slightest smell of propane or gas because odor loss is a very real occurrence that could impact you. Additionally, if you have potential problems with your ability to smell propane, this is another reason to not wait and to act immediately upon smelling propane.

A GREAT WORKAROUND in the event of propane odor loss or in the event that certain people cannot smell propane:  BUY A PROPANE GAS DETECTOR!

Understand Your Propane Supply

As a preventative action in propane detection, you must first understand how propane gets into your home so that you can then act properly to eliminate risk and/or respond appropriately in the event of an emergency. Propane is usually transported to your domicile as a very cold liquid inside of a transportable storage container (aka “propane tank”). The liquid form of propane transforms into a gas form right before it is pumped out of the tank. 

Propane tanks are usually white in color so that they can redirect heat and prevent the pressure inside the tank from getting too high. The purpose of the protection on the top of the tank is to defend several mechanisms from weather damage, including the tank shut-off valve, which you can close to stop the flow of propane to your home in case of a leak or other emergency. The purpose of the regulator is to regulate the gas pressure upon exiting the tank. The safety relief valve is there to allow gas to exit to tank in the event that the gas pressure inside the tank rises to unsafe levels. This safety relief valve will close once again when the inside tank pressure returns to normal levels. The gauge shows you how much propane is still left in the tank. 

Piping/tubing systems are used to transport propane from the above mentioned white tanks into your home. Depending on the age and geographical location of your home, there may be a secondary pressure regulator on a wall of your house (sometimes outside). This secondary regulator is there to allow another way for you, the homeowner, to have control over the gas pressure. Yet another way to control the gas flow and pressure is to use the shut-off valves existing on each individual pipe that leads to a certain gas appliance (i.e. the pipe behind your furnace should have a shut off valve). A flexible tube makes the final delivery of the gas to the appliance connecting the gas pipe to the appliance itself.

How to Keep Your Home Safe While You’re Away

  • Turn off propane appliances and turn off/close all propane supply valves.
  • Turn off/close the gas valves on the pipes near your individual gas appliances.
  • Turn off/close your gas at the propane tank.
  • After getting back to your household after the lengthy time away, exercise caution when turning your supply valve back on.
  • To be 100% safe, you may contact your licensed technician to do a check for leaks before you turn the propane supply back on or re-light your pilot lights.
  • Buy and install a propane detector, at least one for every level of your home which contains a propane appliance.

Running Out of Propane

It is highly recommended to NOT RUN OUT OF GAS. If you allow your propane tank to run out completely, then you may be putting you, your family, and your home at serious risk of having a fire or explosion. If an appliance valve or a gas line is left open when the propane supply runs out, a leak could occur when the system is recharged with propane. Air and moisture could get into an empty or depleted storage tank, which can cause rust build-up inside the tank. Rust can decrease the concentration of the odor of propane, making it harder to smell. If your propane tank runs out of gas, any pilot lights on your appliances will go out. This can be extremely dangerous if not handled properly.

Have a propane distributor or a licensed contractor check all of your appliances and gas lines for leaks before you turn the gas back on.

Manage your propane levels as if it was inventory. Whenever the inventory levels of a business get low, typically the demand planner responsible for that inventory re-orders more of that respective inventory so that the business can continue to operate. Treat your propane delivery no differently. It is recommended to set up automatic delivery with your propane supplier. Additionally, set yourself a reminder (i.e. on your phone, watch, computer, etc.) to pop up and tell you when you need to remember to check the propane level in your propane tank. If the propane in your tank is below 20%, immediately procure more propane.

When Pilot Lights Go Out

Call a professional to re-light your pilots for you. Do not do it yourself.

Pilot Light – a tiny, continually lit flame inside your appliance which serves as the standard ignition device for many propane or natural gas powered appliances. Typically located at the bottom of appliances, the purpose of the pilot light is to ignite the burners that then generate the power source to run the appliance (i.e. the catalyst to fuel the furnace to then heat the home). 

If a pilot light continuously goes out or is difficult for you to light, then there may be a problem with the appliance or even with your propane supply. If the pilot light goes out, do not try to repair the appliance or re-light the pilot light yourself.  Please instead hire a professional contractor to resolve your issue because even worse emergencies can occur if homeowners try to relight or repair a pilot light themselves.

Re-Lighting a Pilot Light

Although not recommended, if you do decide to re-light pilot lights yourself, please be sure to follow the appliance manufacturer’s instructions and user manual for that appliance.

  • When the targeted propane appliance is located in the basement, garage, back porch, or any other enclosed space, please comprehensively air out the space before re-lighting any pilots.
  • Try to detect propane around the appliance. Use a propane detector at the floor level near the appliance (because propane gas is heavier and air and sinks) before re-lighting the pilot.


  • Have any source of ignition (smoking, matches, cell phone, etc.) near the area before re-lighting.
  • Re-light it if a wet or muggy smell exists because it may be hard to smell the propane if this is the case.
  • Re-light the pilot light if there is a smell in the area which could block out the smell or detection of propane.
  • Let anybody else be in the room where you will re-light.
  • Apply any oil to a sticky knob or button on a gas regulation valve because oil may lead to the failure of the regulator valve.
  • Try to force anything into place or bend anything when re-lighting.