CNC Safety Standards & Maintenance Practices 2

Question 1

When performing a lockout/tagout (LOTO) procedure on a CNC machine, what is the correct sequence of steps?

Accepted Answer

Notify affected employees, shut down equipment, isolate energy sources, apply locks

Answer

LOTO requires notifying affected employees first, then shutting down and isolating all energy sources before applying locks and tags.

Question 2

Which type of fire extinguisher is appropriate for a CNC machine electrical fire?

Accepted Answer

Class C

Answer

Class C extinguishers are designed for electrical fires and use non-conductive agents that won't create shock hazards.

Question 3

What is the primary hazard associated with a worn or damaged CNC machine way cover?

Accepted Answer

Chip and coolant intrusion damaging linear guides and ball screws

Answer

Damaged way covers allow chips and coolant to contact and abrade the precision linear guides and ball screws, causing premature wear.

Question 4

Under OSHA 29 CFR 1910.217, point-of-operation guarding on CNC machining centers must prevent the operator from reaching into the:

Accepted Answer

Danger zone during the hazardous portion of the machine cycle

Answer

Point-of-operation guards must physically prevent operator contact with the danger zone during any hazardous part of the machine cycle.

Question 5

A CNC operator notices hydraulic fluid pooling beneath the machine. The correct immediate action is to:

Accepted Answer

Stop the machine, place absorbent material, and tag out the machine for maintenance

Answer

Hydraulic leaks create slip hazards and indicate potential system failure; the machine must be stopped and tagged out for repair.

(CNC) Computer Numerical Control Machinist Technical Practice Test