This manual has been prepared as an aid to employers, employees, machine
manufacturers, machine guard designers and fabricators, and all others
with an interest in protecting workers against the hazards of moving
machine parts. It identifies the major mechanical motions and the general
principles of safeguarding them. Current applications of each technique
are shown in accompanying illustrations of specific operations and
machines. The methods described here may be transferred, with due care,
to different machines with similar hazards. To determine whether or not
safeguarding meets the requirements of the standard, any mechanical motion
that threatens a worker's safety should not remain unguarded.
The approaches to machine safeguarding discussed in this manual are not
the only solutions which meet the requirements of the standard. Why?
Because practical solutions to safeguarding moving machine parts are as
numerous as the people working on them. No publication could keep pace
with all of these solutions or attempt to depict them all.
In machine safeguarding, as in other regulated areas of the American
workplace, to a certain extent OSHA standards govern function and
practice. This text, however, is not a substitute for the standards. It
is a manual of basic technical information and workable ideas which the
employer may use as a guide to achieve compliance. It offers an overview
of the machine safeguarding problem in the industrial setting, an
assortment of solutions in popular use, and a challenge to all whose work
Many readers of this manual already have the judgment, knowledge, and
skill to develop effective answers to problems yet unsolved. Innovators
are encouraged to find here stimulation to eliminate mechanical hazards
facing America's workers today.