Milling machines | Safeguarding for Specific Types of Machinery

Electrically powered milling machines cut metal using a rotating cutting device called a milling cutter. These machines cut flat surfaces, angles, slots, grooves, shoulders, inclined surfaces, dovetails, and recessed cuts. Cutters of different sizes and shapes are available for a wide variety of milling operations.
Add a note hereMilling machines include knee-and-column machines, bed-type or manufacturing machines, and special milling machines designed for special applications. Typical milling operations consist of selecting and installing the appropriate milling cutter, loading a work piece on the milling table, controlling the table movement to feed the part against the rotating milling cutter, and calipering or measuring the part.
Milling machine hazards
Add a note hereThe following procedures are frequent causes of amputation from milling machines:
§  Add a note hereLoading or unloading parts and calipering or measuring the milled part while the cutter is still rotating.
§  Add a note herePerforming servicing and maintenance activities such as setting up the machine, changing and lubricating parts, clearing jams, and removing excess oil, chips, fines, turnings, or particles while the milling machine is either stopped but still energized, or while the cutter is still rotating.
§  Add a note hereGetting jewelry or loose-fitting clothing entangled in the rotating cutter.
Case History 
Add a note hereAn employee was using a milling machine to cut metal samples to length. After a part had been cut, the employee needed to gauge the part size. While he was checking the edge of the sample, the blade caught the tip of his glove, pulled his hand into the cutting area, and amputated his right ring finger and part of his middle finger.
Add a note hereSource: OSHA IMIS Accident Investigation Database
Milling machine safeguards
Add a note hereYou should implement the following engineering, work practices, and administrative controls:
§  Add a note hereInstall self-closing guards that enclose the milling cutter when the table has been withdrawn.
§  Add a note hereInstall an interlocked barrier guard around the table. When equipped with a cutter blade brake, the brake should be applied when opening or removing the interlocked barrier guard.
§  Add a note hereUse other safeguarding devices such as splash shields, chip shields, or barriers if they provide effective protection to the operator and when it is impractical to guard cutters without interfering with normal production operations or creating a more hazardous situation.
§  Add a note hereInstruct operators not to use a jib or vise that prevents the point of operation guard from being adjusted appropriately.
§  Add a note hereDevelop and implement safe work practices for machine operators and conduct periodic inspections to ensure compliance.
§  Add a note hereEnsure that all operators receive appropriate on-the-job training by experienced operators until they can work safely on their own.
§  Add a note hereInstruct operators to move the work holding device back to a safe distance when loading or unloading parts and calipering or measuring the work and not to perform these activities while the cutter is still rotating unless the cutter is adequately guarded.
§  Add a note hereProhibit operators from reaching around the cutter or hob to remove chips while the machine is in motion or not de-energized.
§  Add a note hereInstruct operators to remove fines, turnings, or particles only with a brush while the cutter is stopped.
§  Add a note hereInstruct operators to place the jib or vise locking arrangement so that force must be exerted away from the milling cutter.
§  Add a note hereInstruct operators not to leave the cutter exposed after withdrawing work piece.
§  Add a note hereInstruct operators to turn off the milling machine when not in use or when left unattended for any period of time.
§  Add a note hereInstruct employees not to wear gloves, jewelry, or loose-fitting clothing while operating a milling machine and to secure long hair in a net or cap.
§  Add a note hereInstruct operators to perform servicing and maintenance activities under an energy control program in §1910.147.

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Drill presses | Safeguarding for Specific Types of Machinery



Add a note hereElectrically powered drill presses use a rotating boring bit to drill or cut holes in wood or metal. The holes may be cut to a desired preset depth or completely through the stock. A basic drill press operation consists of selecting an appropriate drill bit, tightening the bit in the chuck, setting the drill depth, placing the material on the drill press bed, securing the work to the bed so that it will not rotate during drilling, turning the drill press on, and pulling the drill press lever down so that the drill bit will be lowered into the stock.
Drill press hazards
Add a note hereAmputations typically occur when the operator’s gloves, loose-fitting clothing, or jewelry become entangled in the rotating drill bit. Here are some other causes of drill press-related amputations:
§  Add a note hereInadequately guarding points of operation or power-transmission devices.
§  Add a note herePerforming servicing and maintenance activities such as changing pulleys and belts, changing or tightening drill bits, lubricating the drill press, and cleaning the drill press without de-energizing the drill press.
§  Add a note hereMaking adjustments to the drill press such as setting the depth, securing the material to the drill press bed, and repositioning the wood or metal while the drill bit is still rotating.
Case History 
Add a note hereA mechanic amputated the first joints of his left index and middle fingers while changing the belt position on a multi-pulley drill press. While the mechanic was pulling the belt on, it suddenly went around the outside pulley, pulling the mechanic’s fingers through the nip point.
Add a note hereSource: OSHA IMIS Accident Investigation Database
Drill press safeguards
Add a note hereFor drill presses, you can install guards and other controls and perform work practices:
§  Add a note hereInstall guarding over the motor, belts, and pulleys.
§  Add a note hereInstall an adjustable guard to cover the unused portion of the bit and chuck above the material being worked.
§  Add a note hereReplace projecting chucks and set screws with non-projecting safety-bit chucks and set screws.
§  Add a note hereCover operator controls so that the drill press cannot be accidentally turned on.
§  Add a note hereDevelop and implement safe work practices for drill-press operations and conduct periodic inspections to ensure compliance.
§  Add a note hereTrain and supervise all operators until they can work safely on their own.
§  Add a note hereInstruct employees not to wear gloves, jewelry, or loose-fitting clothing while operating a drill press and to secure long hair in a net or cap.
§  Add a note hereMake sure operators secure material to the drill press bed with clamps before drilling, so that the material will not spin and strike the operator. The operator should not manually secure the work to the drill press bed while drilling holes.
§  Add a note hereDo not adjust the drill press while the drill bit is still rotating.
§  Add a note hereUse the drill press only for its intended purposes.
§  Add a note hereShut off the drill press when not in use or when left unattended for any period of time.
§  Add a note hereRemove the chuck immediately after each use.
§  Add a note herePerform appropriate servicing and maintenance activities under an energy control program §1910.147.

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Meat-cutting band saws | Safeguarding for Specific Types of Machinery

Band saws can cut wood, plastic, metal, or meat. These saws use a thin, flexible, continuous steel strip with cutting teeth on one edge, that runs around two large motorized pulleys or wheels. The blade passes through a hole in the work table where the operator feeds the stock. Blades are available with various teeth sizes, and the saws usually have adjustable blade speeds.
Add a note hereUnlike band saws used in other industries, meat-cutting band saws are usually constructed of stainless steel for sanitary purposes and for easy cleaning. The table, which may slide or roll, has a pushing guard installed to protect the operator while feeding the saw. Meat-cutting band saws may also be equipped with a fence and pushing guard to feed the meat through the band saw.
Meat-cutting band saw hazards
Add a note hereAmputations occur most frequently when operators’ hands contact the running saw blade while feeding meat into the saw. The risk of amputation is greatest when operators place their hands too close to the saw blade, in a direct line with the saw blade, or beneath the adjustable guard during feeding operations. Here are some common causes of amputations involving meat-cutting band saws:
§  Add a note hereThe operator’s hand slips off the meat or otherwise accidentally runs through the blade.
§  Add a note hereThe operator attempts to remove meat from the band saw table while the blade is still moving.
§  Add a note hereThe operator’s gloves, jewelry, or loose-fitting clothing became entangled in the saw blade.
Case History 
Add a note hereAn operator amputated the tip of his right ring finger while using a band saw to cut 1/4-inch slabs of meat from a 4-inch thick piece of beef. As the piece of meat got smaller, his hands moved too close to the saw blade. The employee was not using the pusher guard provided for the saw.
Add a note hereSource: OSHA IMIS Accident Investigation Database
Meat-cutting band saw
Add a note hereEngineering controls you can use include the following:
§  Add a note hereInstall a guard over the entire blade, except at the working portion, or point of operation of the blade. The guard must be adjustable to cover the unused portion of the blade above the meat during cutting operations.
§  Add a note hereEnclose the pulley mechanism and motor completely.
§  Add a note hereInstall a brake on one or both wheels to prevent the saw blade from coasting after the machine shut off.
§  Add a note hereProvide a pushing guard or fence to feed meat into the saw blade.
Work practice and administrative controls
Add a note hereThe following work practice and administrative controls will help ensure safety in your workplace:
§  Add a note hereDevelop and implement safe operating procedures for meat-cutting band saws to ensure the guards are adequate and in place and that operators safely perform feeding methods. Conduct periodic inspections of the saw operation to ensure compliance.
§  Add a note hereEnsure that all operators receive adequate on-the-job training under the direct supervision of experienced operators until they can work safely on their own.
§  Add a note hereInstruct operators to adjust the point of operation guard to admit only the meat.
§  Add a note hereInstruct operators to use the pushing guard or fence to feed the saw, especially when cutting small pieces of meat.
§  Add a note hereInstruct operators to use only sharp meat-cutting blades and to tighten blades to the appropriate tension.
§  Add a note hereInstruct operators not to wear gloves, jewelry, or loose-fitting clothing while operating a band saw and to secure long hair in a net or cap.
§  Add a note hereProhibit operators from removing meat from the band saw while the saw blade is still moving.
§  Add a note hereInstruct operators to turn off and unplug band saws when not in use or when left unattended for any period of time.
§  Add a note hereInstruct employees to perform servicing and maintenance activities under an energy control program in accordance with §1910.147.
Add a note hereIf the band saw is a cord and plug connected equipment for which exposure to the hazards of unexpected energization or start up of the equipment is controlled by the unplugging of the equipment from the energy source and by the plug being under the exclusive control of the employee performing the servicing and maintenance, §1910.147 does not apply.

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