Machine Guarding
Where Guarding Is Required
1910.212 requires one or more methods of machine guarding to protect the operator and other employees from the point of operation, ingoing nip points, rotating parts, and flying chips and sparks. Guards must be attached to the machine where possible, must not create a new hazard, and must not be easily bypassed. Hand-feeding stock into the point of operation calls for push sticks, blocks, or other hand tools. Fan blades less than 7 feet above the floor must be guarded with openings no larger than 1/2 inch.
Power Transmission and Abrasive Wheels
1910.219 requires belts, pulleys, shafts, chains, and gears to be guarded when within 7 feet of the floor or working platform. For abrasive wheel machinery (1910.215), the work rest is kept adjusted to within 1/8 inch of the wheel face, and the adjustable tongue guard to within 1/4 inch of the wheel - both readjusted as the wheel wears down.
Lockout/Tagout (1910.147)
LOTO applies to servicing and maintenance where unexpected energization, startup, or release of stored energy could injure an employee. It requires a written program, machine-specific energy control procedures, training for authorized, affected, and other employees, and a periodic inspection at least annually. Lockout is preferred; tagout alone is permitted only where the machine cannot be locked and the employer demonstrates equivalent protection. The classic exception: cord-and-plug equipment that is unplugged with the plug kept under the exclusive control of the servicing employee.
Traps and a Rule of Thumb
Traps: swapping 1/8 and 1/4 inch; assuming LOTO applies to routine production jams (it addresses servicing and maintenance); letting anyone but the person who applied a lock remove it; accepting a guard that blocks only frontal access.
Rule of thumb: lock out, release stored energy, verify zero energy - then put your hand anywhere near the point of operation.