Breathing Air Quality Testing to BS EN 12021
Breathing air testing confirms whether compressed air supplied to breathing apparatus is suitable for people to breathe.
Velocity Safety tests air supplied from compressors, cylinders and breathing-airline systems used in spray booths, confined spaces, industrial workplaces and other environments where workers rely on an independent air supply.
Testing assesses the quality of the air delivered to the wearer, including:
- Oxygen content: Confirming the air contains a suitable concentration of oxygen.
- Carbon monoxide: Checking for dangerous contamination from compressor exhaust, combustion or system faults.
- Carbon dioxide: Identifying elevated levels that could make the air unsuitable for breathing.
- Oil contamination: Checking for oil mist or vapour introduced by the compressor or filtration system.
- Water content: Assessing moisture that may affect air quality, equipment performance or the breathing-air system.
- Odour: Confirming the supplied air is free from noticeable contamination or objectionable smells.
The results are compared with the applicable requirements of BS EN 12021, with a clear report showing the readings, test location and any action required.
Quick Answer: What is breathing air testing?
Breathing air testing checks the purity and composition of compressed air supplied to breathing apparatus. It helps confirm that workers using airline respirators, breathing-air compressors or cylinders are not being supplied with harmful levels of carbon monoxide, carbon dioxide, oil, moisture or other contamination.
A wide variety of industries and applications use breathing air including:
- Manufacturing
- Paint Spraying
- Confined Space
- Emergency Services
- Healthcare
- Dental
- Pharmaceutical
- Oil and gas
- Holistic Therapies
- Scuba diving centres and training schools
- Commercial Diving Contractors
Where Breathing Air Quality Testing Is Required
Breathing-quality air is required wherever workers depend on compressed air or gas supplied from an independent source rather than filtering the surrounding workplace atmosphere.
Velocity Safety tests breathing-air systems used across:
- Spray booths and automotive refinishing: Air-fed respiratory protection used during paint spraying and work with hazardous coatings.
- Confined spaces: Breathing apparatus used in tanks, vessels, chambers, tunnels and restricted-access environments.
- Manufacturing and engineering: Compressed-airline systems used during processes involving dusts, fumes, gases or vapours.
- Emergency and rescue services: Cylinders, compressors and breathing apparatus used during response and rescue work.
- Healthcare and dental environments: Specialist compressed-air systems where the applicable air-quality standard requires verification.
- Pharmaceutical and laboratory settings: Controlled environments involving hazardous substances or respiratory protection.
- Oil, gas and petrochemical sites: Breathing-air systems used during maintenance, shutdowns and hazardous-area work.
- Commercial diving and training: Specialist breathing-gas applications assessed against the appropriate standard for the activity.
Testing can be completed at the compressor, cylinder outlet, breathing-air manifold or point of use, depending on the system and the purpose of the assessment.
Breathing Air Testing Requirements
Employers must ensure that breathing apparatus supplies air of a suitable quality and that respiratory protective equipment remains effective for the conditions in which it is used.
Breathing-air quality should be assessed:
- Before a newly installed system is placed into service.
- At suitable periodic intervals determined by the system, risk assessment, manufacturer guidance and working conditions.
- After the compressor, intake or system has been moved or significantly altered.
- Following maintenance, repair or replacement that could affect the air supply.
- Where contamination is suspected or users report unusual odours, tastes or symptoms.
- Where workplace conditions change and could introduce exhaust fumes, vapours or other contaminants into the compressor intake.
A three-month testing interval is widely used for compressor-supplied breathing air and is specifically referenced by HSE in certain applications. More frequent testing may be needed where contamination could occur within that period.
The testing frequency should therefore reflect the actual breathing-air system and risk rather than relying on the calendar alone.
Breathing Airline Testing (EN12021)
In environments where air-fed RPE is used – such as spray booths, confined spaces, or industrial workspaces – it’s essential to verify the quality of the breathing air being supplied.
Velocity Safety offers Breathing Airline Testing in accordance with EN 12021, ensuring your air supply is:
- Free from contaminants like carbon monoxide, oil mist, and water vapour
- Delivered at the correct flow rate and pressure
- Fully compliant with HSE and manufacturer requirements for RPE systems
- Tested using calibrated instruments with full traceability
Whether you’re using compressors or cylinders, our testing service ensures compliance, protects your workforce, and gives peace of mind during audits or regulatory visits.
What Does a BS EN 12021 Breathing Air Test Check?
The test assesses the compressed air at an appropriate sampling point and compares the recorded results with the applicable breathing-air quality requirements.
| Test Parameter | Why It Is Checked | Possible Sources of Failure |
|---|---|---|
| Oxygen content | Confirms that the supplied gas contains a suitable level of oxygen for breathing. | Incorrect gas mixture, system contamination or supply issues. |
| Carbon monoxide | Detects a highly hazardous gas that may enter the air supply without being noticed by the wearer. | Compressor exhaust, nearby engines, combustion sources or poor air-intake positioning. |
| Carbon dioxide | Identifies elevated concentrations that could affect the suitability of the breathing air. | Contaminated intake air, poor ventilation or system recirculation. |
| Oil mist or vapour | Checks that lubricant or compressor oil is not contaminating the supplied air. | Worn compressors, unsuitable lubricants, filtration failure or poor maintenance. |
| Water content | Assesses moisture that may affect air quality, equipment reliability or cold-weather operation. | Inadequate drying, saturated filters, condensation or poor system drainage. |
| Odour | Confirms that the air is free from noticeable smells that may indicate contamination. | Contaminated intake air, oils, solvents, exhaust fumes or dirty pipework. |
If a result falls outside the applicable requirements, the breathing-air supply should not be assumed safe until the cause has been investigated and corrected.
Our Breathing Air Testing Process – Compliant with BS EN 12021:2014
We help you verify that the air your team breathes is safe, clean, and compliant. Here’s how our process works:
1. Pre-Test Equipment Check
We inspect the compressor, airline, or cylinder setup to confirm safe testing conditions.
2. Sampling Point Selection
Air is tested at the breathing apparatus coupling or dedicated test port – as close to end-user delivery as possible.
3. Real-Time Analysis & Sampling
Using calibrated test kits, we analyse for key parameters: oxygen content, CO, CO₂, oil mist, water vapour, and odour.
4. Documentation & Standards Comparison
Test results are benchmarked against BS EN 12021:2014 requirements and HSE expectations.
5. Certification & Action Plan
You receive a detailed report including pass/fail status, results breakdown, and any remedial advice.
If your air fails the test, we’ll explain the likely cause and what you need to do to restore compliance.
Why choose Velocity Safety Ltd
Why choose Velocity Safety Ltd for your Breathing Air Testing requirements.
- Trained engineers
- Air tested in accordance with EN 12021.
- Calibrated electronic instrumentation used for complete traceability.
- We can test both low and high pressure up to 300 bar.
- Over 12 years experience in the health and safety industry.
- Our consultants hold occupational hygiene qualifications.
- Fully Insured
- Fast turnarounds available
- Mobile service available nationwide
- Advice and guidance available
What Others Say About Us…
Whether it’s confined space teams or spray booth operators – clients trust our testing to keep their air systems clean and compliant.
“After many issues with the inspectors from our insurer I contacted Ross to quote. He saved us just over £3000 in the first year. He also does weekends for us to reduce downtime.”
Joe, Civils Company Midlands
“After spending £20k purchasing the wrong powered air units for our factory on our previous PPE supplier/H&S advisors recommendations, Ross came in and told us what we needed, why we needed it and what cost savings could be had over the life of the equipment. I just wish we found him sooner.”
David, Engineering Company North West
“Great Service, Great guy nothing is too much trouble.”
John, Groundworks Company North West
Other Services Available:
- Sales, service, repair and refurbishment of confined space equipment.
- Air fills available.
- Gas monitor calibrations
- PSSR Examinations
- LEV Testing
- Respirator face fit testing
- LOLER Examinations
- RPE & RPD Examination and servicing
- Fire Extinguisher Servicing
- PFPE Examinations
- Fall Arrest Block and winch servicing
- Eyebolt testing
- Slip Testing
- Consultancy
FAQs – Breathing Air Quality Testing
Breathing air compliance is critical in confined spaces and hazardous environments. Here’s what employers and safety managers need to know:
What is breathing air quality testing?
Breathing air quality testing checks compressed air or gas supplied to breathing apparatus to confirm that it is suitable for people to breathe.
The assessment commonly includes oxygen, carbon monoxide, carbon dioxide, oil contamination, water content and odour, with the results compared against the applicable requirements of BS EN 12021.
What is BS EN 12021?
BS EN 12021 is the standard specifying quality requirements for compressed gas supplied for use in respiratory protective devices.
It addresses the composition and purity of the breathing gas, including oxygen content, contaminants and moisture.
What does a breathing air test check for?
Velocity Safety tests key breathing-air parameters including oxygen content, carbon monoxide, carbon dioxide, oil mist or vapour, water content and odour.
The appropriate test and sampling method depend on the compressor, cylinder or airline system being assessed.
Is breathing air testing a legal requirement?
Employers must ensure that respiratory protective equipment is suitable, maintained and capable of protecting the wearer. Where breathing apparatus relies on compressed air or gas, the supplied air must be of suitable breathing quality.
Testing provides evidence that the supply has been assessed against the relevant quality requirements and helps employers demonstrate that the system is being properly managed.
How often should breathing air be tested?
Testing should be completed before a new system is first used and then at suitable intervals based on the equipment, risk assessment, manufacturer instructions and working environment.
A three-month interval is commonly used for compressor-supplied breathing air, with more frequent testing where contamination is foreseeable. Additional testing may also be needed after relocation, repairs, alterations or suspected contamination.
Where should a breathing air sample be taken?
The sample should normally be taken from a point that represents the air delivered to the wearer, such as the breathing-apparatus coupling, manifold, test port or end of the airline.
The correct location depends on the system layout and the purpose of the assessment.
Can you test breathing-air compressors?
Yes. Velocity Safety tests low- and high-pressure breathing-air compressor systems, including air delivered through breathing airlines and suitable cylinder-filling arrangements.
Testing can be carried out at an appropriate delivery or point-of-use connection.
Can you test cylinders and high-pressure systems?
Yes. We can test breathing-air supplies from cylinders and high-pressure systems up to 300 bar, subject to suitable access and safe sampling arrangements.
What happens if breathing air fails the test?
The affected supply should not be assumed safe for breathing use until the cause has been investigated and suitable corrective action completed.
Possible causes include contaminated intake air, compressor faults, saturated filters, oil carryover, excess moisture or poor system maintenance. We provide the recorded results and practical remedial recommendations.
Will I receive a breathing air test certificate?
Yes. You will receive a digital report or certificate showing the sampling location, test date, recorded results, applicable standard and overall outcome.
Where an issue is identified, the report will also record the failure and recommended next steps.
Can breathing air testing be completed on-site?
Yes. Velocity Safety provides mobile breathing air quality testing at client premises using calibrated portable equipment.
We support individual sites and multi-location organisations across the UK.
Can testing be completed without shutting down the entire site?
In many cases, testing can be completed with limited disruption by isolating or accessing the relevant compressor, airline or sampling point.
Whether any equipment must be temporarily taken out of service depends on the system configuration and the safe testing procedure.
Do you provide breathing air testing near me?
Yes. Velocity Safety provides breathing air testing throughout the North West and across the wider UK.
Our mobile service supports spray booths, confined-space teams, factories, emergency services and organisations operating breathing-air systems across multiple locations.
Can breathing air testing be combined with other services?
Yes. Testing can often be coordinated with related services such as RPE examination and servicing, face fit testing, gas monitor calibration, LEV testing or PSSR examinations.
Combining services can reduce site visits and simplify compliance scheduling.
Whatever your Breathing Air Testing requirements are you can be sure you’re in honest, reliable and safe hands.
Contact Velocity Safety today 01254 933 486 or Contact Us
Schedule Breathing Air Quality Testing
Confirm your compressed air supply is safe for breathing use. Our BS EN 12021 testing service checks for contaminants and oxygen levels – keeping your air systems compliant and staff protected.
01254 933 486
info@velocitysafety.co.uk
Velocity Safety
Unit 7 Whitebirk Enterprise Centre,
Lower Phillips Road,
Blackburn,
Lancashire
BB1 5UD
