CSA Z462:21
The Canadian standard on Workplace Electrical Safety, CSA Z462, has been updated. A current PDF copy can be purchased online from the CSA Store.
A Brief Look at Some of the Changes
New Arc Flash Category
The recently (January) released 2021 edition of CSA Z462 – Workplace Electrical Safety in Canada – has included a new and unique Arc Flash PPE Category to supplement the existing Z462 Categories of 1, 2, 3 and 4 which are rated at 4, 8, 25, and 40 cal/cm2 respectively.
CSA Z462 now adds Arc Flash PPE Category 5 rated at 75 cal/cm2 to their Table 6C as a new and additional method to choose arc flash PPE for AC voltages.
Z462 references these changes in the 2021 standard at Clauses 4.3.5.5, 4.3.5.7, 4.3.7.3.15.2, 4.3.7.3.15.4, B.2, H.1, and H.2, Annex V, and Tables 6C and H.1 in the standard’s text.
Table 6A Has Been Modified
A new additional single-equipment type is now included at Table 6A described as 600 V class switchgear (with power circuit breakers or fused switches) and 600 V class switchboards rated at Arc Flash PPE Category 5. (Three specific parameter requirements as per information in Table 6A are required).
Annex V
A new normative Annex V described as Arc flash PPE Categories has also been added to CSA Z462:21. Table 6A or Annex V, Table V.1 can be used to select PPE for AC voltages dependent on the specifically described equipment types constrained by the assigned electrical parameters as noted in Z462.
Annex V, Figure V.1, describes a well laid out procedural flow chart to be able to select arc flash PPE for the significantly expanded equipment types found in Table V.1.
Figure V.1 will determine either an Arc Flash PPE Category as N/A, 2, 4 or 5 and arc flash boundary, or that an incident energy analysis method is required.
The CSA Z462:21 Technical Committee’s goal was to assist those in the workplace who may have struggled with portions of the previous Arc Flash PPE Category Method with the addition of this supplemental information.
If Arc Flash PPE Category 5 (75 cal/cm2) is determined from Table 6A or Annex V, Table V.1, for the specific equipment types described, then Table 6C is used as a listing of protective clothing and PPE which now also includes Category 5.
Conclusion
Readers are strongly encouraged to refer to the entire text of the current edition of CSA Z462 when selecting their electrical PPE, equipment and safe work practices. Every actual field situation can be different, and comprehensive Shock and Arc Flash Risk Assessments need to be executed by fully competent and trained personnel.
(Note: The Arc Flash PPE Category 5 and Annex V have NOT been included in NFPA 70E – 2021)
