Non-ATEX certified overpressure protection devices must not be used in zone 2 explosive atmosphere environments. Zone 2 exclusively requires ATEX-certified equipment that complies with European Directive 2014/34/EU. The use of non-certified overpressure protection devices in these zones poses a serious safety risk and is legally prohibited.
What does zone 2 classification mean for overpressure protection devices?
Zone 2 is an area where explosive atmospheres can only form under abnormal conditions and remain present for only short periods. For overpressure protection devices, this means that all equipment must comply with specific ATEX safety requirements to prevent ignition of explosive gases or vapours.
Within ATEX Directive 2014/34/EU, explosive atmosphere zones are classified based on the probability and duration of explosive atmospheres. A zone 2 explosive atmosphere environment represents the lowest risk level of gas hazardous zones, but still requires strict safety measures.
Overpressure protection devices in zone 2 must have specific protective measures against:
- Spark formation from electrical contacts
- Hot surfaces that can reach ignition temperatures
- Electrostatic discharges
- Mechanical friction that can cause sparks
The temperature classification of the equipment must correspond to the ignition temperature of the substances present. This means that the maximum surface temperature of the overpressure protection device must always remain below the ignition temperature of the explosive mixture.
Why is ATEX certification important for overpressure protection devices?
ATEX certification for overpressure protection devices is legally required in zone 2 environments, as it guarantees that the equipment functions safely without causing explosion risks. The certification confirms that the product has been extensively tested and complies with all European safety standards for explosive atmospheres.
The legal requirement arises from ATEX Directive 2014/34/EU, which requires manufacturers to certify their equipment before it may be used in explosive atmosphere zones. For employers, the obligation comes from Directive 1999/92/EC to use only certified equipment in these environments.
Using non-certified overpressure protection devices in zone 2 has serious consequences:
- Safety risks: Increased risk of explosions due to uncontrolled ignition sources
- Legal liability: Personal and corporate liability in case of accidents
- Insurance problems: Possible exclusion of coverage for damage
- Fines and sanctions: Enforcement measures by supervisory authorities
ATEX certification ensures standardised safety in industrial nitrogen systems and other critical applications where overpressure protection devices must provide protection in explosive atmosphere zones.
What alternatives exist for non-ATEX certified overpressure protection devices?
For non-ATEX certified overpressure protection devices, three main alternatives exist: replacement with ATEX-certified equipment, relocation to safe zones, or technical modifications that prevent equipment from being placed in explosive atmosphere environments.
The most direct alternative is replacing the existing overpressure protection device with an ATEX-certified variant. These devices are specially designed for zone 2 safety regulations and have the appropriate protective measures against ignition risks.
Adapted installation locations offer a practical solution:
- Relocation outside zone 2: Placement in safe zones with adapted piping
- Remote mounting: Use of extended connections to safe locations
- Separated compartments: Installation in separated spaces with adequate ventilation
Technical solutions that meet safety requirements include:
- Intrinsically safe systems with energy limitation
- Pressure transmitters with ATEX-certified sensors
- Electronic overpressure protection devices with certified components
- Redundant safety systems outside the explosive atmosphere zone
For overpressure protection devices in geothermal installations, hybrid solutions are often chosen, where primary detection takes place in safe zones and secondary protection is carried out ATEX-compliant.
How do you determine if an overpressure protection device is suitable for zone 2?
An overpressure protection device is suitable for zone 2 when it has valid ATEX certification, the correct temperature classification and gas group marking that correspond to the specific environmental conditions. The equipment must be marked with “II 3G” for zone 2 gas applications.
Practical checklist for assessing suitability:
Check certification requirements:
- Valid EU type examination certificate present
- CE marking with ATEX notified body number
- Category 3 certification for zone 2 application
- Declaration of conformity from manufacturer available
Verify technical specifications:
- Temperature class (T1 to T6) suitable for the substances present
- Gas group (IIA, IIB or IIC) corresponding to the process medium
- Protection type (e.g. “n” for non-sparking equipment)
- Operating temperature range suitable for the application environment
Check installation requirements:
- Earthing and equipotential bonding correctly implemented
- Protection degree (IP rating) adequate for environmental conditions
- Mounting instructions according to manufacturer specifications
- Maintenance procedures in accordance with ATEX directive and zone 2 requirements
In case of doubt about suitability, professional advice from ATEX specialists is essential for a safe and compliant installation of industrial overpressure protection systems.
How Presscon helps with ATEX-compliant overpressure protection devices
We design and supply ATEX-compliant overpressure protection devices that fully comply with zone 2 safety regulations for industrial nitrogen and compressed air installations. Our expertise in explosion-proof equipment ensures reliable protection in critical environments such as geothermal installations, laboratories and data centres.
Our ATEX expertise includes:
- Custom design: Overpressure protection devices specifically adapted to your zone 2 environment
- Complete certification: All equipment provided with valid ATEX documents
- Integral solutions: Complete systems including sensors, control panels and safety circuits
- Maintenance support: Periodic inspections and certificate renewal
For complex projects, we offer comprehensive advice on ATEX compliance, risk analyses and optimal system configurations. Our experience with various industries enables us to provide practical solutions that combine safety and operational efficiency, including specialised solutions such as an ATEX vacuum overpressure protection device for specific applications.
Do you have questions about ATEX-compliant overpressure protection devices for your project? Contact us for a no-obligation consultation about your specific safety requirements and technical challenges.
Frequently Asked Questions
How long does the process take to replace existing non-ATEX overpressure protection devices with certified alternatives?
Replacing non-ATEX overpressure protection devices typically takes 4-8 weeks, depending on system complexity and delivery times. This includes engineering, fabrication, installation and commissioning. For critical installations, we recommend a phased approach to ensure business continuity.
What are the costs of upgrading to ATEX-compliant overpressure protection devices compared to standard equipment?
ATEX-certified overpressure protection devices typically cost 30-50% more than standard equipment due to special materials, design and certification processes. However, this investment is offset by avoided fines, lower insurance costs and especially the increased safety of your personnel and installation.
Can existing overpressure protection devices be adapted or modified to become ATEX-compliant?
No, existing non-ATEX equipment cannot be modified to become ATEX-compliant. Any modification would invalidate the original certification. The only safe solution is complete replacement with new ATEX-certified equipment that is specifically designed and tested for explosive atmosphere environments.
How often must ATEX-certified overpressure protection devices be inspected and maintained?
ATEX equipment requires annual visual inspections and detailed checks every 3 years by qualified personnel. Additionally, monthly function tests are recommended. The exact maintenance frequency depends on environmental conditions and manufacturer specifications, but regular maintenance is crucial for maintaining ATEX certification.
What happens if non-ATEX equipment is discovered being used in zone 2 during an inspection?
Upon discovery of non-ATEX equipment in zone 2, it must be immediately taken out of service until replacement is possible. Supervisory authorities can impose fines up to €870,000 and in extreme cases initiate criminal prosecution. Additionally, your insurance may refuse coverage for damage caused by non-compliant equipment.
How do I determine the correct temperature class and gas group for my specific application?
The temperature class is determined by the lowest ignition temperature of the gases or vapours present, while the gas group depends on the maximum experimental safe gap (MESG) of the gas. Consult safety data sheets of your process media and have an ATEX specialist perform a risk analysis for the correct classification.