is compressed oxygen flammable

Is compressed oxygen flammable? Well, it is natural to think about it when you compress and store this gas within a cylinder or a tank.

This method has been around since 1868, and despite technological advancements, it is still regarded as a good way to store oxygen.

But the problem arises when you do not realize how to take proper safety measures. And that makes many people wonder, “is oxygen a flammable compressed gas?”

Yes, compressed oxygen gas is flammable, and it is possible to cause a fire or explosion by opening the valve of an oxygen cylinder too quickly.

Is Compressed Oxygen Flammable?

yellow warning sign

We are all familiar with oxygen as a gas. With every breath we take, we breathe in oxygen.

It’s the gas that allows life on our planet to exist. And being a gas, oxygen has specific properties.

Left in the atmosphere, oxygen has no definite shape or volume.

Oxygen is perfectly safe as a free-flowing gas in the atmosphere. It is not a flammable gas by itself, although it does help other materials catch fire and burn more easily.

Once it is confined by a container, oxygen, like all gases, will spread itself out to take the shape of the container. Compressed oxygen is a gas under pressure.

In this form, the gas is highly flammable.

How does Oxygen Behaves Under Pressure?

Under pressure, oxygen becomes a flammable compressed gas.

Under normal circumstances when the gas is free-flowing, its molecules are loosely connected and widely dispersed.

They are free to move and are in fact termed ‘highly’ kinetic. That is why they are not inflammable in this state. But, it changes when the gas is compressed.

Understanding More about Oxygen Under Pressure

woman spraying air freshener

We notice this effect daily in other gases, such as those in aerosol air fresheners that have added perfume.

As the aerosol releases the trapped gas, it spreads out and fills the space it is in. We can smell the perfume even if we are nowhere near the aerosol when the gas was released.

This is how in its natural state, oxygen is dispersed evenly through the atmosphere. We don’t tend to experience pockets of oxygen, at least not on Earth.

Tip: Avoid using homemade adaptors and stick to pressure regulators suitable for compressed oxygen to stay safe.

Why Is Compressed Oxygen Flammable?

As well as being involved in respiration in all living things, animals, and plants, oxygen has other uses and is particularly useful when compressed. 

What Difference Does Compression Make to Oxygen?

compressed oxygen tank

Compressing oxygen forces a change in its natural properties and it becomes flammable and capable of burning.

Under compression, the gas is forced and contained in a much smaller volume than it would use up naturally.

But the oxygen molecules once had as much space as they wanted to move around freely, they are now pressed closer and closer together.

It means that when compressed, oxygen molecules have significantly less room to move around.

But, the fact is each molecule of oxygen still has the same level of kinetic energy as it had when allowed to be free moving.

The difference now is that the energy has nowhere to go. Instead, it crashes up against the side of the container it is compressed into.

This can have explosive consequences. 

An Important Consideration

Whatever the planned uses, it takes specialist equipment to contain and pressurize oxygen.

To ensure the force of pressurized oxygen doesn’t dramatically punch through its container, heavy-duty cylinders are needed.

But, unfortunately, they are not always as reliable as they need to be.

In certain circumstances they can fail, causing the oxygen to explode through the cylinder to rapidly escape its confines, usually accompanied by fire.

Tip: When storing compressed oxygen or any other compressed gas, ensure that the temperature stays below 125F. 

What are the Uses of Compressed Oxygen?

oxygen tank in a hospital room

 Compressed oxygen is used in two main areas, medical and industrial.

In medical use, compressed oxygen is used in:

  • The treatment of respiratory illnesses
  • During medical procedures
  • As part of ongoing oxygen therapy

Compressed Oxygen in Medical Setting

There can be no underestimating the role of oxygen in healthy living. Virtually all processes and systems in the body make use of it.

Although we usually take our oxygen directly from the air we breathe, many people have benefited from oxygen therapy administered either at home or in a medical setting.

The Role of Oxygen Therapy

Oxygen therapy is used to ease the symptoms of many health conditions, including:

  • Severe asthma
  • Cystic fibrosis
  • COPD
  • Pulmonary fibrous
  • Hypertension
  • Heart failure

It can also be of benefit to people who are struggling with their mobility because of obesity and who may have developed other conditions.

Home oxygen therapy is especially helpful for people who may not need hospital care but are dealing with general breathlessness, persistent coughing, fatigue and memory problems at home.

Regulation of Compressed Oxygen

nurse holding oxygen mask

Although we need oxygen to live, too much can be detrimental to health.

The gas has to be administered in small doses, either as pure oxygen or diluted and combined with other gases.

To help manage this, each cylinder of compressed oxygen comes with a regulator attached, tubing and a mask or nasal cannula.

It is a one-way system that allows the patient to take in oxygen as they inhale but closes the system on the exhale. The system also prevents waste.

This is especially important if the patient is using a cylinder at home when even a small cylinder is awkward, cumbersome and heavy.

Industrial Uses of Compressed Oxygen

Compressed gases are widely used in industry. It is often mixed with other gases.

When it comes to compressed oxygen, you will notice its use in various industrial sectors.

It may be used in:

  • Cutting, welding, brazing and soldering to give a higher flame temperature.
  • Steel working where oxygen converts carbon to carbon dioxide gas. 
  • The exothermic reaction is used when cutting steel to blow away metal oxide
  • Thermal lancing, where oxygen is used to create the high temperatures needed to cut through materials like brick, stone or concrete.

Besides these uses, there are many other ways compressed oxygen is utilized these days.

For instance:

Use in Diving

scuba tank and flippers

Compressed oxygen plays a big role when it comes to recreational diving.

It is used by trained technical divers who mix it with other gases (nitrox or trimix). They sometimes use it pure to extend bottom times and to speed decompression. 

Use in Climbing

Nowadays, you can find many professional mountain climbers relying on compressed oxygen for better performance.

In mountain climbing, it is used as supplemental oxygen in two ways:

  • To decrease the effects of altitude
  • To encourage the blood flow into the hands and feet

Use in Wastewater Treatment

In wastewater treatment, compressed air is often used to blow organic particles from the water.

modern urban wastewater treatement plant

Aeration of wastewater involves introducing oxygen into the water in order to promote aerobic biodegradation of many different pollutants.

It is a vital component of any biological wastewater system.

The treatment relies on microorganisms found naturally in wastewater to decompose wastewater contaminants.

Tip: Be careful when storing compressed oxygen cylinders and ensure that you keep them in a dry, well-ventilated area.

Staying Safe Around Flammable Compressed Oxygen

Because oxygen is so highly flammable under pressure, it is unwise to smoke around it and it has to be handled with caution.

To render the compressed oxygen safe for home use, all cylinders come with pressure-release devices that release gas if the pressure reaches dangerous levels.

However, if the cylinder is ever crushed or heated, it could still explode. Friction heat is created when the trapped oxygen explodes from the cylinder that causes the gas to catch fire.

Handling a Leaking Oxygen Regulator

medical oxygen pressure regulator

While oxygen concentrators and tanks used in the home are generally safe, they are not completely risk-free for those who require life-saving oxygen therapy.

Leaks in oxygen tanks are one of the most prevalent issues with these devices, and they pose a serious health risk if left unchecked.

And oxygen regulators are more susceptible to leakage.

Dealing with a Leaking Regulator

A regulator is used in order to ensure that the patient receives oxygen safely and effectively. 

Oxygen regulators are susceptible to wear and tear just like the rest of the components in an oxygen system. If this occurs, oxygen could escape from your tank and pose a risk of fire and explosion.

If you suspect a leakage, you should check different components to identify the problem.

For instance:

  • Check its seal washer and replace it if it seems damaged.
  • Check if the regulator is aligned properly and fix it if needed.

However, if the regulator seems to have a relief valve leak, is cracked, or has been damaged in any way, you should get a new one or have it checked out by a professional.

Tip: Learn about different hazards, including chemical reactivity, explosion, pressure, and corrosivity around compressed oxygen to stay safe. 


oxygen tank without regulator

Is compressed oxygen flammable? In its loose form, oxygen is pretty safe, but it all changes once you compress it and store it within a container.

It makes it a lot more dangerous because the molecules do not have enough space to travel in a locked space. 

So, you have to be careful when around an oxygen cylinder and never open it suddenly to avoid any issues.