Breathing Systems Resource Page
Industrial Service Solutions – Breathing Air Systems
What Is Compressed Breathing Air?
Compressed breathing air is produced by a specialized breathing air compressor and purification system. The air is purified and supplied to protect workers who are exposed to hazardous conditions such as sandblasting, spray painting, chemical spill clean-up, welding, grinding, pipe cleaning, tank cleaning, and other industrial activities where repeat exposure may cause health threats.
Regulatory Standards for Breathing Air
In the United States, the Occupational Safety and Health Act (OSHA) requires the use of Grade D breathing air. This standard, published by the Compressed Gas Association under G-7.1, defines acceptable limits for contaminants.
Carbon Monoxide: Maximum of 10 parts per million by volume
Carbon Dioxide: Maximum of 1,000 parts per million
Oil (Condensed Hydrocarbons): Maximum of 5 milligrams per cubic meter
Odor: Lack of any noticeable odor
Dew Point: As required to prevent condensation
In Canada, the Canadian Standards Association (CSA) sets similar but stricter standards, requiring lower contaminant limits such as 5 parts per million carbon monoxide and 500 parts per million carbon dioxide.
Breathing air systems must include carbon monoxide detectors, temperature safety shut-offs, and pressure regulators to comply with Grade D breathing air requirements. Importantly, these systems do not add oxygen, so intake air must always come from a safe, uncontaminated source.
How Breathing Air Systems Work
A complete compressed breathing air system is composed of:
Breathing air compressor
Aftercooler
Dryer (desiccant or refrigerated)
Catalytic converter
Adsorber
Filter
These components remove oil, water, hydrocarbons, odors, and contaminants, delivering purified breathing air that meets or exceeds OSHA and CSA standards.
Types of Breathing Air Systems
Constant Flow Systems
Constant flow systems are the most common in industry. They deliver a continuous stream of purified air into the worker’s respirator. This method minimizes the possibility of outside contaminants entering the respirator. Constant flow is used in highly toxic or harmful environments.
Demand Flow Systems
Demand flow systems operate by allowing the worker’s breathing to open and close the air valve. Air enters during inhalation and closes during exhalation. This method conserves air but creates slight negative pressure, which may allow contaminants to leak into the respirator if the seal is not perfect. These systems are typically used with compressed air cylinders and tight-fitting respirators.
Pressure Demand Systems
Pressure demand systems provide continuous positive pressure inside the respirator. When the worker inhales, more air is delivered instantly. Because the respirator remains pressurized, contaminants are kept out. This design is suitable for environments with toxic contaminants, but like demand flow, requires a properly fitted respirator.
Breathing Air Purifiers – Sizing and Selection
Industrial Service Solutions offers several categories of breathing air purifiers. Sizing is based on maximum inlet flow (standard cubic feet per minute), operating pressure (pounds per square inch gauge), and ambient conditions.
Disposable Cartridge Breathing Air Purifiers – Maximum inlet flow of 45 standard cubic feet per minute at 250 pounds per square inch.
Continuous-Duty Desiccant Breathing Air Purifiers – Maximum inlet flow of 920 standard cubic feet per minute at 150 pounds per square inch. Available as portable or stationary models.
Refrigerated Breathing Air Purifiers – Maximum inlet flow of 150 standard cubic feet per minute at 150 pounds per square inch.
Breathing Air System Options
Disposable Breathing Air Purifiers
Disposable filters remove oil and gaseous hydrocarbons but do not remove carbon monoxide. They are best suited for facilities that need breathing air occasionally. Elements must be changed every 2,000 hours, and operating costs become high when a constant supply of breathing air is required.
Continuous-Duty Desiccant Breathing Air Purifiers
These systems include multiple purification stages: filters, desiccant dryers, catalysts, and carbon filters. Portable models handle up to 150 standard cubic feet per minute, while stationary units can handle up to 1,000 standard cubic feet per minute.
Refrigerated Breathing Air Purifiers
These purifiers include chillers, coalescers, adsorption filters, catalysts, and particulate filters. They are designed for adjusted flows up to 150 standard cubic feet per minute. Higher flows require a continuous-duty desiccant system.
Installation and Maintenance Guidelines
Disposable Purifiers: Install upstream of workers, operate below maximum pressure and temperature limits, change filters at 2,000 hours, and drain condensate daily.
Desiccant Purifiers: Must be installed in controlled environments between 35°F and 100°F. Inlet air must be dry and below 100°F. Regular maintenance includes daily inspection, filter changes every four months, desiccant inspection every six months, and catalyst replacement annually.
Refrigerated Purifiers: Install indoors in ambient air between 50°F and 100°F. Maintenance includes daily indicator checks, weekly draining, monthly condenser cleaning, quarterly filter replacement, and annual catalyst replacement.
Why Choose Industrial Service Solutions for Breathing Air Systems?
Full range of breathing air compressors, dryers, and purifiers available online.
Compliance with OSHA Grade D and CSA standards.
Expert assistance and guidance from our customer service team.
Reliable shipping across the United States.
Contact us today at 888-996-1152 or email [email protected] to learn more about breathing air systems or request a customized solution.