CSA Z62.3-11:2016 pdf download.Chain saw kickback
4.1.2 Replacement saw chains
Saw chains sold as replacement equipment for a specific chain saw model originally evaluated in accordance with Clause 4.2.2 (Class A chain saws), 4.2.3 (Class B chain saws), or 4.2.4 (Class C chain saws) shall, when evaluated with that chain saw model, enable that chain saw model to meet the acceptance criteria of Clause 4.2.2, 4.2.3, or 4.2.4, respectively. Alternatively, replacement saw chains for Class A and C chain saws shall meet the requirement for low-kickback saw chains specified in Clause 4.1.3.
4.1.3 Low-kickback saw chain
A replacement saw chain may be designated "low- kickback saw chain" if the computed kickback angle without brake (CKAwob) does not exceed 45° when tested on the generic kickback unit (GKU) as specified in Clause 6.
Note: To allow a transition for manufacturers to qualify replacement saw chains by the use of a GKU, a method of using chain saws may also be used to qualify replacement chains, similar to that used in the previous edition of this Standard (see Clause 6 and Table 1). The Technical Committee intends to remove this from the next edition of this Standard.
4.2 Chain saws
4.2.1 General
Clause 4.2 specifies kickback limits for chain saws (see Table 2). Evaluation shall be conducted on complete saws as they are offered to the end-user. The test method specifies requirements for evaluating the saw both with and without the use of a chain brake.
Note: See Clause 7.1.3 for chain saw marking requirements.
4.2.2 Class A chain saws
When evaluated in accordance with Clause 5, Class 1A and 2A chain saws shall not exceed 45° CKAwb or 45° CKAwob, or the moving chain shall be stopped before the chain saw exceeds a 45° computed kickback angle (CKAcs). The CKAwob or CKAcs shall be used for evaluation purposes unless the computer program yields the result "chain stopped after bar peak", in which case the CKAwb may be used.
4.2.3 Class B chain saws
When evaluated in accordance with Clause 5, Class 1B and 2B chain saws shall not exceed 25° CKAwb or 25° CKAwob, or the moving chain shall be stopped before the chain saw exceeds a 25° computed kickback angle (CKAcs). The CKAwob or CKAcs shall be used for evaluation purposes unless the computer program yields the result“Chain stopped after bar peak", in which case the CKAwb may be used.
4.2.4 Class C chain saws
When evaluated in accordance with Clause 5, Class 1C and 2C chain saws shall not exceed 45° CKAwb or 45° CKAwob, or the moving chain shall be stopped before the chain saw exceeds a 45° computed kickback angle (CKAcs). The CKAwob or CKAcs shall be used for evaluation purposes unless the computer program yields the result "chain stopped after bar peak' , in which case the CKAwb may be used. CSA Z62.3-11 pdf download.