Page 4 - Insulating Footwear

WHAT ABOUT THE
TECHNICAL DETAILS?
INSULATING (DIELECTRIC) FOOTWEAR FOR LIVE WORKING
EN 50321-1:2018 is the new standard for insulating footwear for live working and was published earlier this year, it replaces EN 50321:1999 and is currently out for approval as an IEC standard which will make it a global standard, not just European.
The main changes in the 2018 revision are the introduction of four new classes (see below) for working up to 36 KV (the old standard only went up to Class 0 - 1 KV). Boots are now tested by filling with water instead of ball bearings to simulate water or perspiration potentiality wicking
up the lining and creating a flash over. There is also now an electrical test after perforation of the sole by a nail, to ensure boots still give electrical protection after perforation. Even non-metallic perforation inserts can allow water to pass through them so will allow an electrical current to pass when the sole is punctured. The table below lists the classes and the test requirements:
Class 00
Class 0
Class 1
Class 2
Class 3
Class 4
Maximum Working Voltage
500V
1kV
7.5kV
17.5kV
26.5kV
36kV
Withstand Test Voltage
5kV
10kV
20kV
30kV
40kV
50kV
Leakage Current Test Voltage
2.5kV
5kV
10kV
20kV
30kV
40kV
Maximum Leakage Current
3mA
5mA (8 mA)
10mA (16 mA)
18mA
20mA
24mA
(Overboot requirements are in brackets where they are different to knee high boots)
The new standard also includes requirements for DC current; all boots used for DC must be tested for DC according to the new standard and this is available as an option (contact us for details).
RE-TESTING DIELECTRIC FOOTWEAR
Not many people are aware that Annex B2 of the standard for dielectric footwear - EN 50321:2000 (Electrically insulating footwear for working on low voltage installations), requires that all approved dielectric footwear is re-tested every year. This is why WorkmasterTM boots have a space to record periodic inspection testing next to the CE markings on the boot. This requirement applies to all CE marked dielectric footwear from every manufacturer - if boots are not re-tested then they are effectively no-longer compliant to the standard.
Dielectric boots under test at the WorkmasterTM boot factory
04 DIELECTRIC FOOTWEAR FOR LIVE WORKING