Machinery and equipment present a danger to employees because many have hot, fast-moving parts, which can burn workers or ensnare their clothing. OSHA (Occupational Safety and Health Administration) regulations for machine guards are in place to prevent such occurrences. Employers are required to provide one or more types of guards to protect the machine's operator and other employees. These include barrier guards, two-hand tripping devices and electronic safety devices, among others. However, the installation of these safety devices does not prevent all accidents—many workers still injure themselves and their colleagues.

Proper machine guarding prevents many hazards, including ingoing nip points, rotating parts, flying chips and sparks. They occur during shearing, punching, forming and assembling. A general guideline is that guards should be attached to the machine itself. These guards should not be dangerous in themselves. The following is a partial list of machines which must be guarded at the point of operation: guillotine cutters, shears, alligator shears, power presses, milling machines, power saws, jointers, portable power tools, and forming rolls and calendars.

Some hazards are subject to the 'seven-foot rule,' which dictates that these potentially dangerous operations be enclosed or guarded if they are located less than seven feet above the floor or platform level. Guards are required to have one-half-inch or smaller openings. Blades and other overhead hazards—such as pulleys, belt rope and chain drives, overhead horizontal belts, vertical and incline belts, gears, sprockets and chains—must comply with this rule.

Workplace violations of guarding requirements are common. In many facilities, out-of-date, unguarded fans, and ones protected by guards with openings that are too big, are in operation. In fact, thousands of floor and wall-exhaust fans used throughout the country are non-compliant. Another common sight is unguarded blades, fans or pulleys, which are within seven feet of the floor or platform level. Oversights also typically occur when machinery is repaired. Guards and safety devices are removed during repair but not replaced afterwards. This neglect leads to their dangerous, unguarded operation.

Unguarded moving parts, such as blades and fans, can injure a worker's hands, limbs or head during accidental contact. For example, an unguarded pulley or shear can ensnare an employee's clothing and pull the worker into a machine. Such hazards are serious health threats and should be immediately eliminated by placing proper guarding or installing new equipment. The following are some basic safety measures that employers should follow to comply with OSHA requirements:

• Rotating and moving equipment parts and pointed objects, such as fan blades or power saws, should be guarded from contact with workers.

• Machinery, pits, holes and hazardous procedures must be sufficiently guarded.

• Metal components of electrical equipment must be bonded and grounded.

• Electrical equipment that creates flames, sparks, arcs, or molten metal should be enclosed and placed far from combustible substances.

• Guards should be placed on chains and gears.

• Machinery should be maintained and kept clean and secure.

• Emergency stop buttons should be red in color.

Power presses are especially dangerous, causing many amputations and other injuries. OSHA specifically addressed power press concerns in 1997 by implementing an education and enforcement program aimed at minimizing power press injuries. Employers of all sizes—from large companies to ones with 10 or fewer workers—must comply. They must install guarding devices, perform routine inspections and maintenance, and provide sufficient training to operators and machine workers. Safety devices—such as those that halt machine operation when a body part touches a dangerous area and barriers that provide protection during the risky stage of operation—should be stable, durable and not hamper the job. Before operating presses unsupervised, workers must complete at least eight hours, and in some cases two weeks, of training. Their training should encompass proper use of all controls and safety devices, correct PPE, secure storage of parts, and equipment testing. Supervisors must be conscious of all hazards, must know how to operate guards, and must enforce correct procedures, including regular repairs and maintenance.

In summary, employees working on or near machinery with hazardous moving parts must be protected. OSHA requires that such parts be guarded to ensure worker safety. If unguarded, those parts could entangle a worker's hands, hair or clothing and lead to injury or even death. Employers therefore should inspect equipment daily to make sure that all guards are intact—especially after maintenance or repair.

Source: OSHA Requirements for Machine-Guarding
Jeffrey L. Hirsch
Plant Engineering, June 21, 2002
http://www.manufacturing.net/ple/index.asp?layout=articleCurrentWeb&doc_id=91661&industry=Environmental&industryid=2129