안전계수는 NfsN dP-dc/dc 공식으로 계산하였으며, 안전계수가 5N+10 이상이면 대체로 안전하다고 판단하였다.
The safety factor was calculated by the formula NfsN (dP-dc)/dc, and if the safety factor was 5N+10 or higher, it was generally considered safe.