It is spring or early fall, the flowers are blooming and the weather is right for outdoor activities. You have been waiting for this opportunity to do some camping coupled with bird watching, fishing, or even some hiking. It time to check the condition of those small propane tanks.
Nothing tops a nice warm meal with camp mates as you reminisce over the day’s activities. But have you ever wondered if your small propane tank expires and what that means for you? Worry no more; here is what you need to know about your propane gas tank expiry.
What is Propane?
Propane gas is a flammable hydrocarbon that is widely becoming a popular source of energy. The propane used as fuel is obtained from the processing of natural gas and crude oil refining process.
Propane gas is colorless, odorless, and has a low boiling point (-44° F) at atmospheric pressure. In the presence of oxygen (present in air) propane gas burns to release moisture and carbon monoxide.
These properties make propane gas a good source of energy that can be stored in a propane tank.
How is Propane Gas Stored and how is it Used?
For use as fuel, propane gas is stored as liquefied gas in pressured propane tanks in the form of either small barbeque gas tanks, large gas cylinders, or even larger LPG (Liquefied petroleum gas) tanks.
Propane gas is commonly used in homes as hot water heaters and for outdoor grilling, for heating power plants in industries, in agriculture to power irrigation machines or forklift, in fleet vehicles and some buses, and outdoors as gas-powered cooking stoves used during camping. It can also be used for refrigerators.
What are the Parts of a Propane Gas Tank?
Propane gas tanks have several connections that serve different purposes. These connections are what make the propane gas tank safe for use during camping or at home. These parts include the following:
- Valves such as the safety/relief valve, fill valve, vapor return valve, service valve, and liquid withdrawal valve.
- The OPD (Overfill protection device) device.
- Gauges including the float gauge and fixed liquid level gauge.
Do Small Propane Gas Tanks Expire?
Propane gas is classified as an LPG (Liquefied petroleum gas) gas and like most LPG gases, propane gas does not go bad and can be used for many years. However, the gas tank or bottle or cylinder it is stored in must be checked and re-certified every 10 years because it has an expiry date which limits its long term use.
Propane gas must be stored in a liquefied form in special pressured tanks failure to which it would revert into its gaseous form. These tanks are liable to wear and tear over the years which could lead to gas leaks that could potentially have devastating consequences.
As a result of public safety, propane gas tanks are highly regulated with different laws existing for different propane tanks in different states or municipalities. Most of the regulations are oriented towards the safe storage, safe handling, and proper use of these propane gas tanks.
Kindly note that propane gas cylinders must be inspected periodically!!!
The small propane gas tanks used for camping have not been exempted from these regulations. Camping propane gas tanks mostly weigh 100 pounds or below.
Propane tanks that weigh 100 pounds or below have a shelf life of 12 years meaning that they can be used for 12 years from the date of manufacture. When 12 years are up you should have the tank inspected for exchange/replacement or requalification for an additional 5 years.
Larger propane tanks used at homes or in industries are regulated directly by the state or municipality.
How can I check the expiry date of my propane tank?
When you inspect your propane gas tank, you will notice letters and numbers stamped on the collar at the top of your propane gas tank. These are important numbers and letters without which your propane gas tank cannot be refilled and that can be used to determine if your propane gas tank is expired. These letters and numbers include:
- The water content (WC) shows how much water your propane gas tank is capable of holding in gallons.
- The tare weight (TW) represents the weight of the empty propane gas tank, for example, TW 18 for 18 pounds.
- The serial number depending on the manufacturer of the propane gas tank.
- The manufacture/certification date which is usually stamped using a month and year format (MM-YY). For example, a tank stamped 05-2020 was manufactured in May 2020. If your tank expires and is recertified, the qualified inspector will add a sticker with an “E” next to the manufacture date which will add 5 years to the expiry date of your propane gas tank.
To calculate the expiry date of your propane gas tank simply add 12 years to the second number of the manufacture date. For example, a tank that was manufactured in 07-2011 will expire in July 2023.
Consequently, if your tank was manufactured more than 12 years ago then it is expired. Propane gas suppliers will not refill your tank if it was manufactured or certified more than 12 years ago.
Why do propane tanks expire?
Old propane gas tanks may have visible rust or other damages on them which could serve as avenues for propane gas leaks posing great potential public hazards as they could lead to the start of fires as propane gas is highly flammable.
Additionally, propane gas has a low boiling point, therefore, it vaporizes easily and as a result, in closed containers, the liquid gas tends to expand which can lead to an explosion and as such, propane tanks are fitted with safety valves which allow some vapor to escape when the pressure exceeds certain levels.
These safety valves need to be evaluated periodically. Propane gas tanks also have a device known as OPD (Overfill protection device) that regulates the valve during refilling. During refilling when the tank reaches a certain capacity the OPD device shuts down the refill valve. If the OPD device is damaged or missing your propane gas tank cannot be refilled.
For safety purposes, states and municipalities have laws and regulations that control the storage, handling, and use of propane gas tanks which is the main reason that propane gas tanks have expiry dates. The laws that govern the use of propane gas tanks are different in each state or municipality.
What if my propane gas tank is expired?
Once you check your propane gas tank and find that it is expired you have two options.
- Find a qualified propane gas tank re-qualifier for your tank to be recertified. Depending on the state of your tank (in good condition without visible rust or damage), the state of its safety features (appropriate safety valves), the date of its initial manufacture (within 12 years), and the rules and regulation in your state, your propane gas tank expiration may be recertified. Recertification extends the expiry date of your propane gas tank by 5 years.
- If your propane gas tank cannot be recertified for one reason or another, you can have the tank exchanged or buy a new one. There exist gas tank exchanging programs depending on the state that you live in. Find out from your local propane gas supplier the program that best suits you.
Why should I check the expiry date of my propane gas tank?
Although propane gas has a long shelf life unlike other hydrocarbons, propane gas tanks do expire and can pose potential hazards to you and your loved ones.
It is therefore advisable to ensure you check the expiry date of your propane gas tank. If it is expired, have the tank recertified by a qualified propane tank professional.
Propane gas tanks are costly, and as such, it is necessary to ensure that if you wish to buy a safe and appropriate tank for that outdoor grilling experience or that camping you have been longing to go to. This is especially important if you want to purchase a second-hand propane gas tank which tends to be more cost-effective.