Many people, when hearing the term “Compressed Air” automatically associate it with aerosol products. However, many people often use the term “Compressed Air” incorrectly. In reality, there is a clear difference between compressed air and compressed gas. In this article, we will explain what compressed air really is, where it is used, what components may be present in compressed gas, and how improper use of aerosol products can pose a hazard.
What is Compressed Air?
Compressed air is atmospheric air that is mechanically compressed using a device such as a compressor. This air retains its natural composition – it is a mixture of nitrogen (about 78%), oxygen (about 21%), and small amounts of other gases (such as argon or carbon dioxide).
Compressed air is widely used in various fields, such as:
- Industry: Pneumatic tools (e.g., drills, grinders, paint guns).
- Transport: Brakes in heavy vehicles and control systems.
- Medicine: Respirators and other medical devices.
- Hobbies and DIY: Cleaning surfaces, powering nail guns.
What is Compressed Gas and What Can Its Composition Be?
In the case of aerosols, such as those used for cleaning electronics or removing dust, we are dealing with compressed gas, not compressed air. Compressed gas is a chemical substance introduced into a can in liquid form under high pressure.
The composition of compressed gas depends on the product’s purpose and may include:
- Propane and butane – the most commonly used highly flammable hydrocarbons (we use a mixture in our products).
- Hydrofluorocarbons (HFCs) – e.g., R134a, used for their cooling properties.
- Carbon dioxide (CO₂) – used in specialized applications.
- Nitrogen (N₂) – used in some applications.
Consequences of Improper Use of Compressed Gas
Aerosols with compressed gas require caution, as improper use can lead to problems. Here are the most common mistakes and their consequences:
Shaking the can:
Shaking mixes the contents of the can, which can cause the release of liquid gas instead of gas in the gaseous phase.
- Why? Inside the can, there is both gas in the gaseous phase and liquid. Shaking disrupts the balance between these phases, causing the liquid to reach the valve.
- Consequence: Release of liquid, which can freeze on the surface of the skin, materials, or inside the can.
Turning the can upside down during application:
Turning the can also causes the release of gas in liquid form instead of gaseous.
- Consequence: This can lead to local freezing of the can, which lowers the internal pressure and affects the product’s effectiveness.
Why is there a fire hazard warning on the can?
Aerosols containing compressed gas must be marked with a flame symbol because their contents are flammable. Our product contains a mixture of propane and butane, which are flammable.
- Hazard: In contact with open flame, a spark, or a very hot surface, the gas can ignite.
- Additional risk: Inside the can, the gas is under high pressure, which means that damage to the can (e.g., puncture) or overheating (e.g., by fire) can cause an explosion.
How to Safely Use Products with Compressed Gas?
To avoid hazards, follow these rules:
- Do not shake the can before or during use.
- Keep the can upright during application.
- Store the can in a cool place, away from heat sources and fire.
- Do not puncture or burn empty cans, even after use.
- Always follow the recommendations on the label.
Summary – Compressed Air vs. Compressed Gas
- Compressed air is clean, natural air mechanically compressed, used in pneumatic devices, medicine, or industry.
- Compressed gas is a chemical substance (e.g., propane, butane) used in aerosols, which requires special caution.
Improper use of products with compressed gas can lead to liquid discharge, can freezing, or dangerous situations related to flammability. Therefore, education and adherence to safety rules are crucial. If you have questions or want to learn more about our office products, contact us.