General Shop Safety
ll tools are dangerous if used improperly or carelessly. Working safely is
the first thing the user or operator should learn because the safe way is the
correct way. A person learning to operate machine tools must first learn the
safety regulations and precautions for each tool or machine. Most accidents are
caused by not following prescribed procedures. Develop safe work habits rather
than suffer the consequences of an accident.
Most of the safety practices mentioned in this section are general in nature.
Safety precautions for specific tools and machines are described in detail in
the chapters along with the description of the equipment. Study these carefully
and be on the alert to apply them.
Using eye protection in the machine shop is the most important safety rule of
all. Metal chips and shavings can fly at great speeds and distances and cause
serious eye injury. Safety glasses must be worn when working with hand cutting
tools, since most hand cutting tools are made of hardened steel and can break or
shatter when used improperly.
There are many different types of safety glasses available in the supply
system; however, the ones that offer the best protection are the safety glasses
with side shields. Safety goggles should be worn over prescription glasses.
HAZARDOUS NOISE PROTECTION
Noise hazards are very common in the machine shop. High intensity noise can
cause permanent loss of hearing. Although noise hazards cannot always be
eliminated, hearing loss is avoidable with ear muffs, ear plugs, or both. These
are available through the local supply system or from the Occupational Health
Clinic. Ear plugs must be properly fitted by qualified personnel.
The floor in a machine shop is often covered with razor-sharp metal chips,
and heavy stock may be dropped on the feet. Therefore, safety shoes or a solid
leather shoe must be worn at all times. Safety shoes also have a steel designed to resist impact.
Some safety shoes also have an instep guard.
GRINDING DUST AND HAZARDOUS FUMES
Grinding dust from abrasive wheels is made up of extremely fine particles of
the metal and the wheel. Some grinding machines are equipped with a vacuum dust
collector. When operating a grinder without a vacuum, wear an approved
respirator to avoid inhaling the dust. Whenever possible, use coolant when
grinding. This will aid in dust control. Grinding dust can be very dangerous to
your health, especially beryllium or parts used in nuclear systems. These
materials require careful control of grinding dust.
Metals such as zinc give off toxic fumes when heated above their boiling
point. Inhaling these fumes may cause temporary sickness, or death. The fumes
produced from lead and mercury are very harmful, as their effect is cumulative
in the body and can cause irreversible damage. When unsure of the materials
being machined, it is advisable to wear a respirator.
PROPER LIFTING PROCEDURES
Using improper lifting procedures may result in a permanent back injury. Back
injury can be avoided if the correct lifting procedures are followed. When
lifting heavy or large objects, get some assistance or use a hoist or forklift.
Objects within your ability can be lifted safely as long as the following
procedures are followed:
- Keep your back straight.
- Squat down, bending at the knees.
- Use the leg muscles to do the work and lift slowly.
- Do not bend over the load
as this will put excessive strain on your spine.
- Carry the object where it is comfortable, and pay close attention to where
you are walking and objects around you.
Exposure to electrical hazard will be minimal unless the operator becomes
involved with machine repair. The machine operator is mostly concerned with the
on and off switch on the machine tool. However, if adjustments or repairs must
be made, the power source should be disconnected. If the machine tool is wired
permanently, the circuit breaker should be switched off and tagged with an
appropriate warning statement. Most often the power source will not be
disconnected for routine adjustment such as changing machine speeds. However, if
a speed change involves a belt change, make sure that no other person is likely
to turn on the machine while the operatorís hands are in contact with belts and
SAFETY RULES FOR MACHINE TOOLS
Since different cutting tools and machining procedures are used on various
machine tools, the safety precautions for each may vary. The following are
general safety rules for any machine tool:
- Gears, pulleys, belts, couplings, ends of shafts having keyways, and other
revolving or reciprocating parts should be guarded to a height of 6 feet above
the floor. The guards should be removed only for repairing or adjusting the
machine and must be replaced before operating it.
- Safety setscrews should be used in collars and on all revolving or
reciprocating members of the machine tool or its equipment.
- Do not operate any machine tool without proper lighting.
- Never attempt to operate any machine tool until you fully understand how it
works and know how to stop it quickly.
- Never wear loose or torn clothing and secure long hair, since these items can
become caught in revolving machine parts.
- Ties should be removed and shirt
sleeves should be rolled up above the elbow.
- Gloves should never be worn when operating machinery except when absolutely
- Always stop the machine before cleaning it or taking measurements of the
- Do not lubricate a machine while it is in motion. Injury to the operator and
damage to the machine may result from this practice.
- Never remove metal chips, turnings, or shavings with your hands; they may
cause a serious cut. If the shavings are long, stop the machine and break them
with pliers or a bent rod, and then brush chips off the machine. Remove
cast-iron chips, which break into small pieces, with a brush. Never wipe away
chips when the machine is operating.
- Always wear safety glasses or goggles while operating machine tools. Also,
wear respiratory protection if operation creates hazardous dust. All persons in
the area where power tools are being operated should also wear safety eye
protection and respirators as needed.
- Know where tire extinguishers are located in the shop area and how to use
- Never wear jewelry while working around machine tools. Rings, watches, or
bracelets maybe caught in a revolving part which could result in the hand being
pulled into the machine.
- Avoid horseplay. Tools are very sharp and machines are made of hard steel. An
accidental slip or fall may cause a serious injury.
- Never use compressed air without a safety nozzle to clean machines or
clothing. It will blow sharp, dangerous metal chips a long distance.
- Keep the floor around machines free of tools, stock, oil, grease, and metal
chips. Tripping over metal on the floor, especially round bars, can cause
dangerous falls. Wipe up all oil, grease, and cutting fluid spills on the floor
as soon as possible to prevent a fall. Metal chips are very sharp and can easily
become embedded in the soles of shoes, making them very slippery, especially
when walking on a concrete floor.
- Never place tools or other materials on the machine table. Cluttering up a
machine with tools or materials creates unsafe working conditions. Use a bench
or table near the machine for this purpose.
- Always use a rag when handling sharp cutters such as milling cutters and end
- Do not expose power tools to rain or use in damp or wet locations.
- Always secure the workpiece. Use clamps or a vise. It is safer than
using your hands, and it frees both hands to operate the tool
- Do not abuse electrical cords. Never carry a tool by its cord or yank it
to disconnect it from a receptacle.
- Keep electrical cords away from heat, oil, and sharp edges.
- Have damaged or worn power cords and strain relievers repaired or
- Remove adjusting keys and wrenches. Form a habit of checking to see that
keys and wrenches are removed from tools before turning them on.
- Do not operate any machine tool while under the influence of drugs,
alcohol, or any medication that could cause drowsiness.
- Store all idle tools in a safe, dry place.
- Provide visitors to the work area required personnel protection equipment.