What is a critical safety consideration when setting jacks or timbers on the face side of the crusher?

A critical safety consideration when setting jacks or timbers on the face side of the crusher is to be aware of the shear location. This is essential because the shear location indicates where material may shift or fall, posing a significant risk to workers. If jacks or timbers are improperly positioned without regard for this shear location, it could lead to equipment failure or an unexpected movement of materials, which in turn increases the likelihood of accidents or injuries.

Understanding the shear location allows for proper placement and securing of jacks or timbers, ensuring that they can effectively support structures and prevent collapse or hazardous situations while work is being performed. Moreover, it emphasizes the need for meticulous attention to physical site conditions, which is fundamental in maintaining a safe working environment.

The other choices address issues that might be relevant in a general context but do not directly confront the crucial safety aspect related to the specific hazards associated with the shear location around the crusher. Prioritizing awareness of the shear location directly impacts the safety and efficiency of the operation.