Once the MAXIMUM CHAIN PULL has been established, the maximum stress that chain components will be subjected to must be considered. It is generally considered that a chain working at 65% of its theoretical ultimate strength will be taken beyond its elastic limit on the tension members of the chain. In order to protect the “running gear” during operation it is necessary to introduce a FACTOR OF SAFETY. The factor of safety is variable but is normally within a range where the ultimate strength or chain breaking load should be between 6 and 10 times the maximum working load. This is dependent on operational environment and service factor and conservative safety factors should be employed where variations in chain pull are difficult to establish. The figure is generally established based on experience and for this reason where uncertainty exists the technical office should be consulted.