There are as many potential hazards created by moving machine parts as there are types of machines. Safeguards are essential for protecting operators from needless and preventable injuries.
Scope and Application
The Occupational Safety and Health Administration (OSHA) requires guarding for any machine where machine parts, functions, or processes may cause injury. The need for machine guarding may be found in machine shops in academic departments, maintenance shops, print shops, and other areas where mechanical equipment is used.
Any machine part, function, or process which may cause injury must be safeguarded. When the operation of a machine or accidental contact with it can injure the operator or others in the vicinity, the hazards must be either controlled or eliminated.
Where Mechanical Hazards Occur
Dangerous moving parts in three basic areas require safeguarding:
Hazardous Mechanical Motions and Actions
A wide variety of mechanical motions and actions may present hazards to the operator. These can include the movement of rotating members, reciprocating arms, moving belts, meshing gears, cutting teeth, and any parts that impact or shear. These different types of hazardous mechanical motions and actions are basic in varying combinations to nearly all machines, and recognizing them is the first step toward protecting operators from the danger they present.
The basic types of hazardous mechanical motions and actions are:Motions
- rotating (including in-running nip points)
Requirements for Safeguards
Safeguards must meet these minimum general requirements:
Protective Clothing and Personal Protective Equipment
Engineering controls that eliminate the hazard at the source and do not rely on the operator's behavior for their effectiveness offer the best and most reliable means of safeguarding. Therefore, engineering controls are the first choice for eliminating machine hazards. But whenever engineering controls are not available or are not fully capable of protecting the operator (an extra measure of protection is necessary), operators must wear protective clothing or personal protective equipment.
If protective clothing and equipment is to provide adequate protection, it must always be:
- appropriate for the particular hazards
- maintained in good condition
- properly stored when not in use, to prevent damage or loss
- kept clean, fully functional, and sanitary.
Protective clothing is, of course, available for different parts of the body. Hard hats can protect the head from the impact of bumps and falling objects when the operator is handling stock; caps and hair nets can help keep the operator's hair from being caught in machinery. If machine coolants could splash or particles could fly into the operator's eyes or face, then face shields, safety goggles, glasses, or similar kinds of protection might be necessary. Hearing protection may be needed when operators operate noisy machines. To guard the trunk of the body from cuts or impacts from heavy or rough-edged stock, there are certain protective coveralls, jackets, vests, aprons, and full-body suits. Operators can protect their hands and arms from the same kinds of injury with special sleeves and gloves. Safety shoes and boots, or other acceptable foot guards, can shield the feet against injury in case the operator needs to handle heavy stock which might drop.
It is important to note that protective clothing and equipment can create hazards. A protective glove which can become caught between rotating parts, or a respirator face piece which hinders the wearer's vision, for example, require alertness and continued attentiveness whenever they are used.
Other parts of the operator's clothing may present additional safety hazards. For example, loose-fitting shirts might possibly become entangled in rotating spindles or other kinds of moving machinery. Jewelry, such as bracelets and rings, can catch on machine parts or stock and lead to serious injury by pulling a hand into the danger area.
Even the most elaborate safeguarding system cannot offer effective protection unless the operator knows how to use it and why. Specific and detailed training is therefore a crucial part of any effort to provide safeguarding against machine-related hazards. Thorough operator training should involve instruction or hands-on training in the following:
Roles and Responsibilities
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