Human Error Threatens Safety in Hazardous Areas

The top 5 problems identified in hazardous areas are

1. Poor or no maintenance on flameproof (Ex d) enclosures. Due to corrosion—especially when equipment is installed outdoors—the Ex d protection is gone 2-3 years after installation.
2. Incorrectly installed Ex d cable glands. Even if the combination of cable and gland is chosen correctly, the instructions on how to install the cable gland and cable are often not followed correctly. As a result, if an explosion occurs, flames will propagate in the Ex d box.
3. Incorrectly installed intrinsic safety (Ex i) circuits. Even if these circuits are well-designed, during installation they may not be separated properly from other non-Ex i circuits. Also, proper earthing is often neglected. As a result, the intrinsic safety of the circuit is not warranted.
4. Water ingress in increased safety (Ex e) enclosures. As a result of water ingress, Ex e distances are affected and a short-circuit, which can lead to a spark and subsequent fire, is possible. Ingress is often the result of using IP grades that are too high (IP65, 66) because temperature changes (e.g. day/night) can lead to water condensation inside the enclosure.
5. Not taking environmental conditions into account. Generally, this aspect affects all the others. Poor design of the Ex installation and less-than-optimal equipment selection become particularly troublesome when the applicable environmental conditions have not been taken into account.

All in all, most problems encountered in explosive environments come down to insufficient quality control. Proper training on the appropriate use of hazardous area equipment can prevent many problems. Additionally, intrinsically safe equipment solutions—when correctly installed—have a lower incident risk during operation and maintenance compared to all other types of protection methods.
 

• Learn more about safe weighing in hazardous areas