ISO air refers to compressed air that has been treated to meet specific purity standards defined by the International Organization for Standardization (ISO) within the ISO 8573-1 standard. This standard classifies compressed air based on the levels of contaminants present, ensuring that the air is suitable for its intended application.
Essentially, ISO air is not a type of air with a unique composition, but rather compressed air that has undergone processing to meet defined purity levels for solid particles, water content, and oil content. Different applications require different levels of air purity, so the ISO 8573-1 standard provides a framework for specifying and achieving the necessary air quality.
Understanding ISO 8573-1
The ISO 8573-1 standard is crucial for industries that rely on compressed air, such as manufacturing, healthcare, and food processing. It defines the quality classes for the three primary contaminants:
- Solid Particles: Measured in terms of particle size and concentration (mg/m³).
- Water: Measured as pressure dew point (PDP) or liquid water content.
- Oil: Measured as the total oil content (aerosols, liquid, and vapor) in mg/m³.
ISO Air Purity Classes: An Example
Each contaminant is assigned a class number, with lower numbers indicating higher purity. For example, air classified as ISO 8573-1:2010 [1:2:1] indicates:
- Class 1 for Solid Particles: Very low particle concentration.
- Class 2 for Water: A pressure dew point of -40°C or lower.
- Class 1 for Oil: Very low oil concentration (≤ 0.01 mg/m³).
Why is ISO Air Important?
Using compressed air that doesn't meet the required purity standards can lead to various problems, including:
- Equipment Damage: Contaminants can corrode or clog pneumatic tools and machinery.
- Product Contamination: In industries like food and pharmaceuticals, impure air can contaminate products.
- Health Risks: In medical applications, contaminated air can pose serious health risks to patients.
- Reduced Efficiency: Contaminants can reduce the efficiency of compressed air systems.
Achieving ISO Air Quality
To achieve the required ISO air quality, various air treatment technologies are used, including:
- Filters: To remove solid particles.
- Dryers: To remove water vapor. Different types of dryers (refrigerated, desiccant) achieve different dew points.
- Oil-Water Separators: To remove liquid oil and water.
- Activated Carbon Adsorbers: To remove oil vapor.
By understanding and implementing the ISO 8573-1 standard, industries can ensure that their compressed air systems provide clean, dry, and oil-free air, leading to improved performance, reduced costs, and safer operations.
