Safety for Mechanical Work 111

belts

A band of flexible material that is looped around two or more fixed pulleys to transmit motion. Belts are made of various materials and come in different types, such as flat belts, round belts, and V-belts.

bleed

The process of safely removing liquid or gas from a closed system. Bleeding is a blockout method.

blocking

An energy-isolation procedure that physically prevents the flow or movement of energy. Blocking is often a failsafe backup to lockout/tagout.

bumpers

An energy absorbing device that reduces impact in case a moving crane reaches the end of its permitted travel or two moving cranes come in contact with each other. Bumpers may also be called rail stops.

capacitor

An electrical device that stores energy and releases it when needed. Capacitors should be grounded during maintenance to avoid injury from electrical shock.

caustic

Capable of destroying organic or inorganic material by chemical action. Caustic substances can cause injury, which can be avoided by wearing appropriate PPE.

certification

Validation that a person or company has achieved a certain standard. Certification may be awarded by a school, a professional organization, or other governing body.

chemical

Any element, compound, or mixture of elements and/or compounds. Chemicals may be solids, liquids, or gasses.

circuit breaker

A safety device that detects overcurrent in a circuit. A circuit breaker often contains a bimetallic strip that bends and trips a switch that opens a circuit.

clamp

To secure a workpiece or machine component in place to keep it from moving. Clamping springs or other machine components under pressure is a safety blocking method.

clearance

An amount of space or distance between two objects. Clearance prevents any part of a crane from colliding with any other object.

combustible

Capable of igniting and burning. Combustible materials can be solid, liquid, or gas.

conveyor systems

A mechanical system consisting of a flexible belt and at least two fixed pulleys that is used to transmit motion. Conveyor systems should have their belts removed prior to maintenance work.

cranes

A device with a hoisting mechanism used to lift, lower, and transport a load. Cranes can be fixed or mobile.

cutting fluids

A fluid used to decrease friction and reduce the temperature of a metal cutting or grinding process. Cutting fluids may contain water, oils, and/or synthetic fluids.

data plate

A metal plate affixed to a powered industrial truck (PIT) by the manufacturer that contains information, such as the weight of the vehicle. Data plates should always be consulted prior to operating a PIT.

dolly

A manually operated cart, generally on two wheels, used for moving heavy objects. Dollies are also known as hand trucks.

downtime

A period of time when a machine or a facility is neither operating nor producing. Downtime should be avoided whenever possible.

duty rating

The maximum weight that a ladder can safely carry. Duty ratings range from Type III, or Light Duty, to Type IAA, or Extra Heavy Duty.

earmuffs

Personal protective equipment that covers the entire outer ear. Earmuffs consist of two ear coverings connected by a band.

earplugs

A protective device that is inserted in the ear to block noise. Earplugs can be made from wax, cotton, foam, silicone, or rubber.

emergency stop

E-stop. A switch that brings a machine to a safe and rapid stop. Emergency stops are important safety features.

energy-isolating mechanism

A mechanical device, such as a circuit breaker or valve, that physically controls the transmission or release of energy. Energy-isolating mechanisms are held in a fixed position during lockout.

E-stop

emergency stop. A switch that brings a machine to a safe and rapid stop. Emergency stops are important safety features.

face shield

A rigid, transparent plastic sheet that covers the worker's entire face to protect against dust or splashes. Face shields do not protect against impacts, so they are often worn with goggles.

fire extinguisher

A portable device that uses a rapid spray of material to put out small fires. A fire extinguisher rated for electrical fires contains a non-flammable gas under extreme pressure and displaces or removes oxygen from the fire.

flammable

Capable of quickly catching fire. Flammable items ignite at low temperatures.

forklift

A type of powered industrial truck (PIT) that has two prongs on the front for lifting pallets of material. Forklifts are one of the most common types of PIT.

fuse

A safety device that detects excess current in a circuit. Fuses often have a component that melts and opens the circuit.

gears

A wheel-shaped device with teeth around the perimeter that is used to transfer force and motion to another device. Multiple gears often interconnect with one another to transfer motion.

gloves

Personal protective equipment worn on the hands and/or arms to reduce the risk of injury. Gloves can protect the skin from chemicals or sharp objects.

goggles

Tight-fitting eye protection that completely covers the eyes, eye sockets, and surrounding facial area. Goggles offer protection from impact, dust, swarf, and splashed liquids.

ground

Safely connecting an electrical component to a neutral body, like the earth, which can absorb a stray electrical charge. Grounding electrical components helps prevent injury from electrical shock.

group lockout device

An item which physically restrains an energy-isolating mechanism from being activated and which can be locked in place using multiple padlocks. Group lockout devices must be used when multiple maintenance personnel are servicing the same machine.

hand tools

A tool that is powered by an operator. Hand tools must be kept clean and sharp in order to avoid injury.

hand truck

A manually operated cart, generally on two wheels, used for moving heavy objects. Hand trucks are also known as dollies.

harness

A personal safety device, composed of a series of straps connected around the legs, waist, and shoulders, that is attached to a hoist. Harnesses are one component used within personal fall arrest systems.

jack stands

A safety device that supports a vehicle that has been raised by a jack. Jack stands are usually used in pairs that keep a vehicle from falling to the ground if the lifting jack is removed or faulty.

jib

A horizontal arm that attaches to the boom of a crane. A jib may be in line with the boom or offset at various angles.

jib cranes

A crane consisting of a tall tower and a horizontal arm called a jib. Jib cranes have a lower maximum weight that can be lifted by the end of their jibs than the maximum weight that can be lifted close to the mast.

lanyard

A flexible line of rope, wire rope, or strap. Lanyards generally have an connector at each end used to attach a body belt or body harness to a deceleration device, lifeline, or anchorage.

lifeline

A fall protection component consisting of a flexible line that hangs either vertically or stretches horizontally and is attached to an anchorage. Lifelines serves as a means for connecting the components of a personal fall arrest system.

lockout device

A safety device that holds an energy isolating device in the safe or "off" position or covers it to make it is inaccessible. Lockout devices are often held shut with a padlock and key.

lockout/tagout

A method of protecting employees by preventing accidental machine startup. Lockout/tagout is performed by proper locking and labeling of machines that are undergoing maintenance.

lubricant

A substance used to reduce friction between two surfaces that move in contact with one another. Lubricants are often applied by maintenance workers.

machine guard

A shield or cover over hazardous areas on a machine. Machine guards prevent accidental contact with body parts and prevent the machine from expelling debris.

main switch

A switch controlling the entire power supply to the crane. Main switches must be open, locked, and tagged prior to performing any maintenance.

mast

A long, vertical tower. Masts are used support the jib on a jib crane.

metatarsal guards

A device that straps onto the shoe to protect the instep from impacts and crushing. Metatarsal guards may be made from aluminum, steel, plastic, or fiber.

non-slip base

A safety device or devices used to prevent a ladder from skidding or sliding. Non-slip bases include rubber safety feet.

Occupational Safety and Health Administration

OSHA. A government agency under the Department of Labor that sets standards for working conditions in the United States. The Occupational Safety and Health Administration helps employers reduce injuries, illnesses, and deaths in the workplace.

OSHA

Occupational Safety and Health Administration. A government agency under the Department of Labor that sets standards for working conditions in the United States. OSHA helps employers reduce injuries, illnesses, and deaths in the workplace.

overhead crane

A crane with a movable bridge carrying a movable or fixed hoisting mechanism that travels on an overhead fixed runway structure. Overhead cranes are used to lift and move heavy loads.

pendant

A hand-held device that crane operators use to precisely control the motions of a crane. Pendants should only be used by trained crane operators.

personal fall arrest system

A system used to stop a fall. Personal fall arrest systems usually consist of an anchorage, connectors, and body harness and may include a lanyard, deceleration device, or lifeline.

personal protective equipment

PPE. Any item that workers wear or use to prevent injury in the workplace. Personal protective equipment includes safety glasses, earmuffs, and gloves.

PITs

Powered industrial trucks. Any mobile, power-propelled truck, other than an earth-moving or road-hauling vehicle, that is capable of carrying, pushing, pulling, lifting, or stacking materials. PITs include forklifts.

powered industrial truck

PIT. Any mobile, power-propelled truck, other than an earth-moving or road-hauling vehicle, that is capable of carrying, pushing, pulling, lifting, or stacking materials. Powered industrial trucks include forklifts.

PPE

Personal protective equipment. Any item that workers wear or use to prevent injury in the workplace. PPE includes safety glasses, earmuffs, and gloves.

press

A machine with a stationary base and an upper ram that moves along a vertical axis to shear, bend, or form sheet metal.

pressure

A force or stress which, when applied, causes changes to the properties of the material. Pressure is typically expressed in pounds per square inch (psi).

rail stops

An energy absorbing device that reduces impact in case a moving crane reaches the end of its permitted travel or two moving cranes come in contact with each other. Rail stops may also be called bumpers.

safety blocks

A device used during maintenance to block the movement of components or lock components in place. The safety block is placed in a machine to prevent injury due to accidental movement.

safety glasses

Protective eyeglasses with metal or plastic frames and impact-resistant lenses that may or may not offer vision correction. Safety glasses often have protective side shields.

scaffold

A raised platform that allows employees to work at elevated heights. Scaffolds are generally constructed of metal bars and platforms and may have wheels.

screwdrivers

A type of hand tool that tightens and loosens screws. Screwdrivers contain a grip on one end and a mating component on the other end that corresponds to the head on the screw.

springs

An elastic device used to dampen and apply force, control motion and vibration, and store energy. Springs are used in many mechanical systems to aid in the storage and transfer of energy.

steel-toed boots

Personal protective footwear made with reinforced steel in the toe area. Steel-toed boots are designed to prevent foot injury from falling objects.

swarf

The combination of chips, fluid, and debris produced during metal cutting or grinding. Swarf can damage vision if it comes into contact with the eyes.

tagout device

A prominent visual warning device that can be securely attached to a machine or power source during repair or maintenance. Tagout devices alert employees that equipment is not to be operated until the tag is removed.

team lift

To pick up and move an object using multiple people. Team lifting heavy objects helps to distribute weight and avoid injury.

valves

A mechanical device that regulates the flow of liquid, gas, or other objects. Valves contain moveable parts that open, close, or obstruct one or more openings or passageways.

wheel chocks

One or more wedges placed behind the wheels of a forklift to prevent it from moving. Wheel chocks must be in place during maintenance activities.

wrenches

A type of hand tool that tightens and turns bolts and nuts. Wrenches contain fixed or moving jaws or a round attachment that grips the nuts or bolts.