Increased safety Ex e

Testing technique  

The increased safety technique is based on the principle that no arcs, sparks or hot surfaces will be generated by equipment or component. This equipment or component will have additional measures to provide increased security against possibility of excessive temperatures, arcs and sparks. 

Testing to standards 

The International standard IEC 60079-7 or Australian/New Zealand standard AS/NZS 60079.7 specifies requirements for design, construction and testing of Ex equipment and Ex components for type of protection Ex e when read in conjunction with the General Requirements standard IEC 60079-0 or AS/NZS 60079.0 respectively. 

Additional measures are employed to ensure that electrical equipment does not produce arcs, sparks, or excessive temperature in normal operation or under specified abnormal condition. 

Here are some common methods used to minimise the risk of arcs, sparks and heat: 

• high quality insulation 
• enlarged creepage and clearance distances 
• high level of Ingress Protection (IP) rating  
• specially designed wiring/harness 
• secured internal connections 
• terminal arrangement for external connections 

Components using other Ex techniques in conjunction with Ex e elements can be Ex component certified for dual types of explosion protection. These components may be found in luminaries, control boxes and other EPL Gb assemblies. 

Equipment Protection Level (EPL)

Equipment Protection Level (EPL) ‘e’ is divided into two based on the risk of the electrical equipment becoming an ignition source in an explosive gas atmosphere:  

• ‘eb’ – EPL Gb or Mb, “high” level of protection, where equipment is not a source of ignition in normal operation or during expected malfunctions 

• ‘ec’ – EPL Gc, “enhanced” level of protection, where equipment is not a source of ignition in normal operation. 

Types of tests 

Here are some tests that may be applicable depending on the construction and material of equipment and these may include but are not limited to:  

• thermal tests 

• thermal endurance to heat and to cold (environmental test) 

• resistance to impact  

• drop tests 

• degree of protection (IP) by enclosure test 

• determination of maximum surface temperature of motors 

• locked rotor tests of motors 

• creepage and clearance measurement 

• CTI Test for insulation material 

• terminal insulating material test 

• surface resistance test  

• dielectric test 

• insulation resistance test. 

Getting the test results

The results of our testing are presented in a test report that is endorsed by our local Australian laboratory accreditation body, NATA (National Association of Testing Authorities, Australia).

When product sample testing, design assessment (Ex test report) and quality assessment (quality assessment report) are successfully completed, an Ex Certificate of Conformity (IECEx or ANZEx) is issued by TestSafe.

Help and support

Complete our online enquiry form.

Call: +61 (2) 4724 4900

Email: testsafe@safework.nsw.gov.au

Mail us at: PO Box 592, Richmond, NSW 2753 Australia.