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 new 4 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 Rating | Maximum Working Voltage | Withstand Test Voltage | Leakage Current Test Voltage | Maximum Leakage Current |
---|---|---|---|---|
Class 00 | 500V | 5kV | 2.5kV | 3mA (5mA) |
Class 0 | 1kV | 10kV | 5kV | 5mA (8mA) |
Class 1 | 7.5kV | 20kV | 10kV | 10mA (16mA) |
Class 2 | 17.5kV | 30kV | 20kV | 18mA |
Class 3 | 26.5kV | 40kV | 30kV | 20mA |
Class 4 | 36kV | 50kV | 40kV | 24mA |
(Overboot requirements are in brackets where they are different from 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).