🛠️ Safe handling starts with the right material
Tools in potentially explosive atmospheres must be specially selected - even if they are not allowed to bear an ATEX marking. The decisive factors for safety are material, workmanship and testing by reliable inspection bodies. In this third part of our series, we shed light on what really matters when it comes to selection.
🧱 Materials in comparison - what is suitable for Ex zones?
| Material | Properties | Suitability for potentially explosive atmospheres |
|---|---|---|
| Copper beryllium (BeCu) | Very hard, corrosion-resistant, non-sparking | ✅ Very well suited |
Titanium-copper | Highly corrosion-resistant, mechanically strong, very low flying sparks | ✅ Very suitable (expensive & rare) |
| Aluminium-Bronze | Robust, chemical-resistant, low sparking | ✅ Well suited |
| Brass | Soft, limited mechanical load capacity | ⚠️ Limited suitability |
| Steel / stainless steel | Hard, spark-forming (depending on alloy) | ⚠️ Only suitable to a limited extent |
| Plastic, glass fiber | Antistatic possible, not mechanically resilient | ⚠️ Only useful as a supplement |
Note: Materials that do not generate ignitable sparks under mechanical stress are required for Ex zones
.
🧪 Exams - and what they really show
Even if ATEX certification is not possible, tools can (and should) be tested:
- ✅ Strike ignition test: Check whether sparks are produced at all and whether they are ignitable.
- ✅ Material analysis: composition, hardness, conductivity
- ✅ Antistatic test: surface resistance with insulated handles
- ✅ Ignition source analysis according to EN ISO 80079-36: For more complex mechanical devices
📄 Certificate from BAM:
An independent test report from the Federal Institute for Materials Research and Testing (BAM) is available for our X-Spark tools. This confirms the suitability of the materials used and the safe behavior under typical mechanical stresses.
🧪 Specialist knowledge: The chromium content in steel influences the ignition behavior.
In a BAM study (Research Report 292), the behavior of various steels under impact stress was investigated. The results were impressive:
Stainless steels with a high chromium content (e.g. X5CrNi18-10 with approx. 18% Cr) generate significantly fewer ignitable sparks than unalloyed or low-alloy steels.
This is because chromium suppresses the oxidation of the torn-off particles - a prerequisite for hot sparks. Although the BAM does not specify a concrete threshold such as ">13 %", the trend is clear: more chromium = less ignition risk.
Practical note: In special cases, a high-alloy stainless steel can be a sensible alternative - but only with a documented risk assessment and a tested application.
🧰 What you should consider when buying
- ✅ Material clearly named (e.g. BeCu, Al-bronze)
- ✅ Test certificate available (e.g. BAM report)
- ✅ No improvised material combinations
- The "EX" logo is not a valid test mark! - Pure manufacturer designation without legal relevance
🧯 Conclusion
Above all, tools for potentially explosive atmospheres must be tested in a safe and traceable manner. More important than a logo:
- 🔬 Material properties
- 🧾 Reliable test reports
- 📦 Quality and condition of the tool
Only in this way can maintenance and repair work in potentially explosive atmospheres be carried out safely and in compliance with the law.