💨 Compressed air = explosion-proof? A dangerous misconception
In potentially explosive areas, many users rely on compressed air machines - on the assumption that they are safer than electrical devices. The thought is obvious: no electricity, no sparks, no problem?
Unfortunately wrong thinking
.
Compressed air systems can also generate mechanical ignition sources - and are therefore not automatically explosion-proof.
🔍 What the ATEX directive really says
The ATEX Directive 2014/34/EU applies to devices that are used in potentially explosive atmospheres and themselves contain potential ignition sources - regardless of the type of drive.
This means:
A machine with a pneumatic drive must also be ATEX-compliant if, for example:
- generated hot surfaces
- can form sparks due to friction or impact
- is electrostatically charged
- contains mechanical ignition sources according to EN ISO 80079-36
🧪 Certification is possible - but not automatic
Compressed air machines can indeed receive an ATEX marking with a number from the notified body - if the manufacturer meets the requirements and follows the certification path. This means
- Complete analysis of ignition sources
- Documentation in accordance with EN ISO 80079-36/-37
- Optional: Testing of a product sample
- Examination and submission of the documents to a notified body
⚠️ Important to know: No mandatory testing by a notified body for zone 1 (category 2)
A widespread misconception:
Even for devices that are to be used in Zone 1 (Category 2G/2D), testing by a notified body is not required.
Instead:
- complete and compliant technical documentation,
- the self-assessment by the manufacturer,
- and internal quality assurance.
As a rule, the notified body only checks the completeness and traceability of the documentation - not automatically the physical device itself.
Only for category 1G/1D (zone 0/20) is an EU type examination with type assessment by a notified body required by law.
🔥 Where ignition hazards can occur due to compressed air
Even without electrics, compressed air-powered machines can be potential sources of ignition:
- Friction in plain bearings or turbines
- Impact energy for chipping hammers, vibrators or grinders
- Spark formation with metallic contact
- Electrostatic charging due to air movement or plastics
- Overheating due to continuous operation without cooling
✅ What you should consider in practice
- 🔍 Is there an ATEX marking with the number of the notified body?
- 📄 Is an ignition source analysis according to EN ISO 80079-36/37 available?
- 📦 Suitability for Zone 1/21 confirmed in writing by the manufacturer?
- 🤝 Communication with explosion protection officers and HSE officers
🧯 Conclusion
Compressed air alone does not protect against explosions. Mechanical ignition sources must also be taken into account and documented. For zone 1, this means
ATEX is mandatory - but no external testing.
The responsibility lies with the manufacturer - and in case of doubt with the operator.