The glossary consists of terms and their definitions used within the EHS web pages. You can use your browser’s built-in search functionality to search within this web page for a specific term. To do this, press Ctrl-F (on a PC) or ⌘-F (on a Mac). You can also view specific terms by clicking on one of the following letters.

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Acceptable Entry Conditions. The conditions that must exist in a confined space to allow entry to and ensure that employees involved with confined space entry can safely enter into and work within the space.

Activation. A routine test procedure conducted on an eyewash or safety shower to ensure operation, access, and hygiene conducted by unit personnel (e.g. lab supervisor or

Acutely Toxic Substance. Produces adverse effects when exposed individuals receive only small doses of that substance for a short period of time (hydrogen fluoride, for example).

Aerial Lift Device. Equipment such as powered platforms, vehicle-mounted elevated and rotating work platforms, extendable boom platforms, aerial ladders, articulating boom platforms, vertical towers, and powered industrial truck platforms.

Aerial Platform Lift. Used as man lifts whenever work is being performed overhead, such as painting tanks, working on pipelines, etc.

Affected Employee. An employee whose job requires them to operate or use a machine or piece of equipment on which servicing is being performed under lockout or tagout or whose job requires them to work in an area in which such servicing or maintenance is being performed.

Airfoil. Found along the bottom and sometimes side edges, airfoils streamline airflow into the hood preventing turbulent eddies at the face that can carry vapors out of the hood. Bottom airfoils also provide a space for room airflow when the sash is completely closed.

Anchor Point. A secure point of attachment for lifelines, lanyards, or deceleration (grabbing) devices.

Angle of Repose. The greatest angle above the horizontal plane at which a material lies without sliding.

Article. A manufactured item that is formed to a specific shape or design during manufacture; that has end use functions(s) dependent in whole or in part upon its shape or design during end use; and that does not release or otherwise result in exposure to a hazardous substance under normal conditions of use or in a reasonably foreseeable emergency resulting from workplace operations.

Attendant. An individual stationed immediately outside one or more permit-required confined spaces who monitors the authorized entrants and who performs all attendants’ duties assigned in this program.

Authorized Employee. A person who locks or implements a tagout system procedure on machines or equipment to perform the servicing or maintenance on that machine or equipment. An authorized employee and an affected employee may be the same person when the affected employee’s duties also include performing maintenance or service on a machine or piece of equipment which must be locked or a tagout system implemented.

Authorized Entrant. An employee who is authorized by the Environmental Health and Safety Office to enter a permit-required confined space.

Auxiliary Power. Control used to lower the aerial platform lift basket in an emergency.

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Baffles. Moveable or adjustable petitions used to create slotted openings along the back of the hood body. Baffles help to keep a uniform airflow across the face of the hood, which eliminates dead spots and optimizes capture efficiency.

Basket. Enclosed area where operator controls the aerial platform lift and performs all necessary work from this area.

Basket Controls. Controls usually located in the front middle of the basket area of an aerial platform lift.

Basket Rotate Left. Control used to only rotate the aerial platform lift basket left.

Basket Rotate Right. Control used to only rotate the aerial platform lift basket right.

Benching System. A method of protecting employees from cave-in by excavating the sides of an excavation to form one or a series of horizontal steps with near-vertical surfaces between the levels.

Blanking or Blinding. The absolute closure of a pipe, line, or duct by the fastening of a solid plate (such as a spectacle blind or a skillet blind) that completely covers the bore and that is capable of withstanding the maximum pressure of the pipe, line, or duct with no leakage beyond the plate.

Bloodborne Pathogen. A potentially infectious human body fluid.

Body Harness (also referred as Full-body harness). An interconnected set of straps that may be secured about a person in a manner that distributes the fall arrest forces over at least the thighs, pelvis, waist, chest, and shoulders with a means for attaching the harness to other components of a personal fall arrest system.

Bypass. Grill opening above face of hood that helps to maintain a constant face velocity independent of the sash position. When the sash is lowered air flows in through the bypass and the hood face. When the sash is raised it blocks the bypass.

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Choke. Control used to help start the aerial platform lift’s gas engine when it is cold.

Combination Units/Safety Stations. Units that consist of both the emergency shower
and an eye/face wash.

Combustible Dust. Solid particles that if in sufficient concentration will ignite and burn rapidly.

Competent Hot Work Supervisor (CHWS). For UA Little Rock employees, the CHWS shall have successfully completed competent person training and examination to be considered competent. For outside contractors, the hot work supervisor shall be identified and the name provided to the project manager. The CHWS cannot be the hot work operator. Failure to properly adhere to UA Little Rock Hot Work Procedures shall result in suspension of competent person authority and possible disciplinary action.

Competent Person. One who is capable of identifying existing and predictable hazards in the surroundings, or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them. The competent person must have had specific training in and be knowledgeable of the OSHA standard: one who has not had appropriate training or does not have specific knowledge cannot be capable of identifying existing and predictable hazards in excavation work or take prompt corrective measures.

Confined Space. By OSHA definition, a confined space is large enough for an employee to enter fully and perform assigned work, is not designed for continuous occupancy by the employee, and has a limited or restricted means of entry or exit. These spaces may include underground vaults, tanks, storage bins, pits and diked areas, vessels, silos, and other similar areas.

Container. Any bag, barrel, bottle, box, can, cylinder, drum, reaction vessel, storage tank, tank truck, or the like that contains a hazardous substance.

Control Measures. A system or device used, or action taken, to control or prevent the introduction of physical or chemical hazards into a confined space.

Current. Term used to describe electric flow measured in amps/amperage. It is current that can cause electric shock.

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Deadman Switch. Foot switch that must be depressed before any of the controls on the aerial platform lift will operate.

Deceleration Device. Any mechanism, such as a rope, grabbing device, rip stitch lanyard, specially woven lanyard, or automatic self-retracting lifeline/lanyard, which serves to dissipate a substantial amount of energy during a fall arrest, or otherwise limits the energy imposed on an employee during fall arrest.

Deceleration Distance. The additional vertical distance a falling person travels, excluding lifeline elongation and free fall distance, before stopping, from the point at which a deceleration device begins to operate.

De-Energized. Electrical devices that are disconnected from all energy sources including direct electric connections, stored electric energy such as capacitors, and stored non-electrical energy in devices that could reenergize electric circuit parts.

Department. Any university or research foundation department that performs work in a confined space or permit-required confined space.

Designated Area. Permanent location designed for or approved by a Competent Hot Work Supervisor (CHWS) for hot work operations to be performed regularly.

Designated Area. A space which has a perimeter barrier erected to warn employees when they approach an unprotected side or edge, and serves also to designate an area where work may be performed without additional fall protection.

Designated Area. Permanent location designed for or approved by a CHWS for hot work operations to be performed regularly.

Double Block & Bleed. The closure of a line, duct, or pipe by closing and locking or tagging two in-line valves and by opening and locking or tagging a drain or vent valve in the line between the two closed valves.

Drench Hose. Hand-held units that are intended to supplement existing shower and eyewash units (but do not replace them).

Drive Forward. Control used to move the aerial platform lift forward.

Drive Reverse. Control used to move the aerial platform lift backwards.

Drive Speed. Control used to set the speed to which the aerial platform lift will travel.

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Emergency. Any occurrence (including any failure of hazard control or monitoring equipment) or event internal or external to the permit-required confined space that could endanger entrants.

Emergency. Any potential occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which may or does result in a release of a hazardous substance into the workplace.

Emergency Shower. A unit that cascades water over the whole body.

Emergency Stop. Control used to kill the aerial platform lift in an emergency situation.

Employee. Any person hired by the university or research foundation as full or part-time personnel, including administrators, faculty, staff, students, and work study students.

Energized Electrical Work. Work conducted by an employee on or near an exposed energized circuit greater than 50 volts and typically less than or equal to 600.

Energy Source. Any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy.

Engine Speed. Control used to set the engine speed of the aerial platform lift.

Engineering Controls. Those controls that eliminate or reduce the hazard through implementation of sound engineering practices.

Engulfment. The surrounding and effective capture of a person by a liquid or finely divided (flowable) solid substance that can be aspirated to cause death by filling or plugging the respiratory system or that can exert enough force on the body to cause death by strangulation, constriction, or crushing.

Entrant. Any employee who enters a confined space.

Entry. The action by which a person passes through an opening into a permit-required confined space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant’s body breaks the plane of an opening into the space.

Entry Permit. The written or printed document that is provided by the company to allow and control entry into a permit-required confined space.

Entry Supervisor. An employee from the Environmental Health and Safety Office (EHS), or their designate, responsible for determining if acceptable entry conditions are present at a permit-required confined space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry as necessary. An entry supervisor may also be an employee from a department other than the EHS who has received advanced training and authorization from the EHS Mnagager to be an entry supervisor. An entry supervisor may act as an authorized entrant as long as that person is trained for such role he or she fills. Also, the duties of entry supervisor may be passed from one individual to another during the course of an entry operation.

Excavation. Any man-made cut, cavity, trench, or depression in earth’s surface formed by earth removal.

Exposure or Exposed. Any situation arising from work operation where an employee may ingest, inhale, absorb through the skin or eyes, or otherwise come into contact with a hazardous substance.

Extending Axles. Axles that extend, used to stabilize the aerial platform lift.

Eye/Fash Wash. A unit that flushes water specifically to the eyes.

Eyewash. A unit that flushes water specifically to the eyes.

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Fixed Ladder. A ladder, including an individual rung ladder, which is permanently attached to a structure, building, or equipment.

Flow Test. An annual test procedure to assess flow, temperature, and pressure characteristics conducted by EHS personnel.

FM. Factory Mutual –An independent product safety testing and certification company.

Forward & Reverse Arrows. Arrows used to indicate travel direction of the aerial platform lift.

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Ground Controls. Controls used to operate the aerial platform lift from the ground in case of an emergency (also known as auxiliary controls).

Ground-Fault Circuit-Interrupter (GFCI). A device designed to disconnect an electric circuit when it seeks ground through a person or grounded object, thus preventing electric shock and fires. It provides additional protection from shocks by shutting off current to equipment when a change in electricity is sensed.

Grounding. Provides a safe path between electricity and the earth, preventing leakage of current; the creation of a conductive path for electricity between a circuit and the equipment to ground.

Guardrail. A barrier at least 42 inches high erected to prevent personnel from falling from working levels more than 30 inches above the floor, ground, or other working areas of a building.

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Hands-Free/Stay-Open Valve. A valve that opens and closes the water supply to the
emergency units and stays open until it is manually turned off.

Hazard Warning. Any words, pictures, symbols, or combination thereof appearing on a label or other appropriate form of warning that convey the health hazards and physical hazards of the substance(s) in the container(s).

Hazardous Atmosphere. An atmosphere that may expose employees to the risk of death, incapacitation, and impairment of ability to self-rescue (that is escape unaided from a permit- required confined space), injury, or acute illness from one or more of the following causes: an oxygen deficient atmosphere containing less than 19.5% oxygen by volume or an oxygen enriched atmosphere containing more than 23.5% oxygen by volume; a flammable gas, vapor, or mist in excess of 10% of its lower flammable limit (LFL) or lower explosive limit (LEL); a hazardous atmosphere of airborne combustible dust; having a concentration of any toxic substance above the VOSH permissible exposure limit (PEL) or the ACGIH threshold limit value (TLV); or any other atmospheric condition that is immediately dangerous to life or health.

Hazardous Material. One that is either a physical hazard (i.e., flammable, oxidizer, etc.) or a health hazard (i.e., causes acute or chronic health effects).

Hazardous Substance. One which by reason of being explosive, flammable, poisonous, an irritant, or otherwise harmful is likely to cause injury or illness.

Hazardous Substance. Any substance which is a physical hazard or a health hazard or is included in the List of Hazardous Substances prepared by the Director pursuant to Labor Code section 6382.

Health Hazard. A substance for which there is statistically significant evidence based on at least one study conducted in accordance with established scientific principles that acute or chronic health effects may occur in exposed employees. The term “health hazard” includes substances which are carcinogenic, toxic or highly toxic agents, reproductive toxins, irritants, corrosives, sensitizers, hepatotoxins, nephrotoxins, neurotoxins, agents which act on the hematopoietic system, and agents which damage the skin, eyes, or mucus membranes.

Heating Mantle. A resistively heated flexible fiberglass shell that conforms to the shape of the reaction flask.

High Degree of Acute Toxicity. A substance which may be fatal or cause damage to target organs as the results of a single exposure or exposures of short duration.

High Voltage. Electrical systems or equipment operating at or intended to operate at a sustained voltage of more than 600 volts.

Hole. A void or gap 2 inches or more in its least dimension in a floor, roof, or other walking/working surface.

Hot Work. Any work involving welding, brazing, soldering, heat treating, grinding, powder- actuated tools, hot riveting, and all other similar applications producing a spark, flame, or heat, or similar operations that are capable of initiating fires or explosions.

Hot Work Permit. A document issued by the Competent Hot Work Supervisor (CHWS) for the purpose of authorizing a specified activity.

Hot Work Operator. An individual designated by UA Little Rock to perform hot work under the authorization of a CHWS.

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Immediate Use. The hazardous substance will be under the control of and used only by the person who transfers it from a labeled container and only within the work shift in which it is transferred.

Immediately Dangerous to Life or Health (IDLH). Any condition that poses an immediate or delayed threat to life, that would cause irreversible adverse health effects, or that would interfere with an individual’s ability to escape unaided from a permit-required confined space.

Inerting. The displacement of the atmosphere in a permit-required confined space by a noncombustible gas to such an extent that the resulting atmosphere is noncombustible. Note: inerting creates an oxygen deficient atmosphere.

Isolation. The process by which a permit-required confined space is removed from service and completely protected against the release of energy and material into the space by such means as blanking or blinding, misaligning or removing sections of lines, pipes, or ducts; a double block and bleed system; lockout or tagout of all sources of energy; or blocking or disconnecting all mechanical linkages.

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Laboratory-Type Hood. A device enclosed except for necessary exhaust purposes on three sides and top and bottom, designed to draw air inward by means of mechanical ventilation, operated with insertion of only the hands and arms of the user and used to contain hazardous substances.

Ladder. A device typically used to gain access to a different elevation consisting of two or more structural members crossed by rungs, steps, or cleats.

Lanyard. A flexible line of rope or strap that generally has a connector at each end for connecting the body harness to a deceleration device, lifeline, or anchor point.

Level Warning Light. Light that indicates that the aerial platform lift base is 5 degrees or more out of level-don’t swing, raise, or scope if out of level.

Lifeline. A component consisting of a flexible line for connection to an anchorage at one end to hang vertically (vertical lifeline) or for connection to anchorages at both ends to stretch horizontally (horizontal lifeline). This serves as a means for connecting other components of a personal fall arrest system to the anchorage.

Lift Down. Control used to lower the aerial platform lift boom down.

Lift Up. Control used to lift the aerial platform lift boom up.

Line Breaking. The intentional opening of a pipe, line, or duct that is or has been carrying flammable, corrosive, or toxic material, an inert gas, or any fluid at a volume, pressure, or temperature capable of causing injury.

Lockout. The placement of a lockout device on an energy-isolating device, in accordance with an established procedure, ensuring that the energy-isolating device and the equipment being controlled cannot be operated until the lockout device is removed.

Lockout Device. A device that utilizes a positive means, such as a lock, to hold an energy-isolating device in the safe position and prevent the energizing of a machine or piece of equipment.

Lockout/Tagout. Placing locks or tags on the energy isolating device to prevent the unauthorized re-energizing of the device or circuit while work is being performed by personnel.

Low Voltage. Electrical systems or equipment operating at or intended to operate at a sustained voltage of 600 volts or less.

Lower Levels. Those areas or surfaces to which an employee can fall. Such areas include, but are not limited to, ground levels, floors, platforms, ramps, runways, excavations, pits tanks, material, water, equipment, structures, or portions thereof.

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Machine Hazard. This occurs at the point of operation where the actual work is performed and can be created by: components which transmit energy, such as pulleys, belts, chains, gears, couplings, or flywheels; or other parts which move while the machine is working, including reciprocating, rotating, and transverse parts.

Material Safety Data Sheet (MSDS). MSDSs are prepared and distributed by manufacturers and distributors of hazardous materials. All chemical manufacturers and distributors must obtain or develop an MSDS for each hazardous material they produce or import.

Maximum Weight Placard. Placard on the aerial platform lift used stating the amount of weight the lift can handle.

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Non-Permit Confined Space. A confined space that does not contain or, with respect to atmospheric hazards, have the potential to contain any hazard capable of causing death or serious physical harm.

Normal Production Operations. The utilization of a machine or piece of equipment to perform its intended production function.

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On/Off Ignition. Control used to turn the aerial platform lift ignition on or off.

Opening. A gap or void 30 inches or more high and 18 inches or more wide in a wall or partition through which personnel can fall to a lower level.

Outriggers. Stabilizing devices used to stabilize the aerial platform lift.

Oven. Commonly used in the laboratory to remove water or other solvents from chemical samples and to dry laboratory glassware before its use.

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Pandemic. Pandemics occur when a novel virus emerges that infects and can be efficiently transmitted between humans. Animals are the most likely reservoir for these emerging viruses.

Permit-Required Confined Space. By OSHA definition, a permit-required confined space has one or more of the following characteristics: contains, or has the potential to contain, a hazardous atmosphere, contains a material with the potential to engulf someone who enters the space, has an internal configuration that might cause an entrant to be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross section, or contains any other recognized serious safety or health hazards.

Personal Fall Arrest System. A system used to arrest an employee in a fall from a working level. It consists of an anchorage, connectors, and body harness and may include a lanyard, deceleration device, lifeline, or suitable combinations of these.

Physical Hazard. A substance for which there is scientifically valid evidence that it is a combustible liquid, a compressed gas, explosive, flammable, an organic peroxide, an oxidizer, pyrophoric, unstable (reactive), or water-reactive.

Polarized Plug. Helps reduce the potential for shock with easily identifiable plugs. One prong is wider than the other and can only be inserted into outlets one way.

Positioning Device System. A body harness system rigged to allow an employee to be supported on an elevated vertical surface such as a wall and work with both hands free while leaning.

Primary Authorized Employee. The authorized employee who has been vested with responsibility for a set number or group of employees performing service or maintenance on machines or equipment subject to lockout or tagout procedures.

Purge. To clear a substance from the object that it is contained in; for example, purging an explosive atmosphere from a tank so that work can be performed safely in the tank.

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Qualified Electrical Worker. A qualified person who by reason of a minimum of two years of electrical training and experience with high voltage circuits and equipment and who has demonstrated by performance familiarity with the work to be performed and the hazards involved. Only a Qualified Electrical Worker is allowed to work on energized conductors or equipment connected to energized high-voltage systems.

Qualified Person. An entry supervisor who is trained to recognize and evaluate the anticipated hazard(s) of the confined space and who shall be capable of specifying necessary control measures to assure worker safety.

Qualified Person. A person, designated by UA Little Rock, who by reason of experience or instruction has demonstrated familiarity with the operation to be performed and the hazards involved. Whether a person is considered to be a “qualified person” will depend upon various circumstances in the workplace. It is possible and, in fact, likely for an individual to be considered “qualified” with regard to certain equipment in the workplace, but “unqualified” as to other equipment. An employee who is undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training and who is under the direct supervision of a qualified person is considered to be a qualified person for the performance of those duties.

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Rescue Team. Those persons designated by the EHSO prior to any permit-required confined space entry to perform rescues from confined spaces.

Resistance. The ease with which electricity flows through the material (conductor). Materials (conductors) with higher resistance properties can become hot. (Measured in ohms)

Restraint Line. A device that is attached between the employee and an anchorage to prevent the employee from walking or falling off an elevated surface.

Retrieval System. The equipment used for non-entry rescue of persons from permit- required confined spaces, including retrieval lines, chest or full body harness, and a lifting device or anchor. A retrieval line is primarily used in vertical confined spaces and shall not be used in confined spaces consisting of horizontal tunnels or spaces where obstructions could increase the hazard to the entrant during emergency non-entry removal.

Roof. Exterior surface on the top of a building.

Rope Grab (grabbing device). A deceleration device that travels on a lifeline
and automatically, by friction, engages the lifeline and locks to arrest a fall.

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Sash. A moveable, see through barrier that closes or opens the face of the hood.

Scaffold. Any temporary elevated or suspended platform, and its supporting structures, used for supporting employees or materials or both.

Self-retracting Lifeline/Lanyard. A deceleration device containing a drum-wound line which can be slowly extracted from, or retracted onto, the drum under minimal tension during normal movement and which, after onset of a fall, automatically locks the drum and arrests the fall (usually within two feet or less).

Servicing and/or Maintenance. Workplace activities such as constructing, installing, setting up, adjusting, inspecting, modifying, and maintaining and/or servicing machines or equipment. These activities include lubrication, cleaning or un-jamming of machines or equipment, and making adjustments or tool changes where the employee may be exposed to the unexpected energizing, start-up of the equipment, or release of hazardous energy.

Sharps. Items that can easily puncture the skin. Examples include glass, pipette tips, razor blades, and needles.

Shield System. A structure (permanent or portable) designed to withstand a cave-in. These structures can be pre-manufactured or job-built in accordance with OSHA 29 CFR 1926.652(c)(3) or (c)(4). These systems are often referred to as “trench boxes” or “trench shields”.

Shoring System. A Mechanical or timber structure designed to prevent cave-in of an excavation.

Sloping System. A Method of preventing cave-in by forming sides inclined at an angle away from the excavation. The angle of incline varies with soil type.

Snap Hook. A connector consisting of a hook-shaped member with a normally closed keeper, or similar arrangement, which may be opened to permit the hook to receive an object and, when released automatically, closes to retain the object. Only locking snap hooks are permitted.

Standard Railing. A vertical barrier erected along exposed edges of a floor opening, wall opening, ramp, platform, or runway to prevent falls of persons.

Start Button. Button used to start the aerial platform lift.

Steer Left. Control used to turn the aerial platform lift left when traveling.

Steer Right. Control used to turn the aerial platform lift right when traveling.

Swing Left. Control used to swing the aerial platform lift boom to the left.

Swing Right. Control used to swing the aerial platform lift boom to the right.

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Tagout. The placement of a tagout device on an energy-isolating device, in accordance with an established procedure, to indicate that the energy-isolating device and the equipment being controlled may not be operated until the tagout device is removed.

Telescope In. Control used to retract the aerial platform lift boom.

Telescope Out. Control used to extend the aerial platform lift boom.

Testing. The process by which the hazards that may confront entrants to a permit-required confined space are identified and evaluated. Testing includes specifying the tests that are to be performed in the permit-required confined space.

Tie-Off. A procedure of connecting directly or indirectly to an anchorage point.

Tilt Down. Control used to tilt the aerial platform lift basket down.

Tilt Up. Control used to tilt the aerial platform lift basket up.

Toe Board. A low protective barrier that prevents material and equipment from falling to lower levels and which protects personnel from falling.

Tornado Watch. This indicates that conditions are right for spawning tornadoes. If a tornado watch is issued, designate an observer to monitor weather conditions. Individuals should observe the sky and listen for further advisories. Ensure that you and others in your area will be able to reach refuge in seconds.

Tornado Warning. This signifies that a tornado has been sighted in the area or that atmospheric rotation has been identified by Doppler Radar. When a tornado warning is broadcast in the Little Rock area (city sirens sound), go immediately to your refuge area.

Trench. A narrow excavation made below the surface of the ground in which the depth is greater than the width and the width does not exceed 15 feet.

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UL. Underwriters Laboratories is an independent product safety testing and certification organization.

Unprotected Sides and Edges. Any side or edge (except at entrances to points of access) of a walking/working surface, e.g., floor, roof, ramp, or runway where there is no wall or guardrail system at least 42 inches high.

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Vertical Lifeline. A component consisting of a vertically hanging flexible line for connection to an anchor point at one end that serves as a means for connecting other components of a personal fall arrest system to the anchor point.

Voltage. Electric potential or potential difference assigned to a circuit or system expressed in volts.

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Walking/Working Surface. Any surface, whether horizontal or vertical, on which an employee walks or works including, but not limited to floors, roofs, ramps, bridges and, runways.

Warning Line Systems. Warning line systems are made up of lines or ropes installed around a work area on a roof. These act as a barrier to prevent those working on the roof from approaching it edges.

Welding & Allied Processes. Those processes such as arc welding, oxy-fuel gas welding, open-flame soldering, brazing, thermal spraying, oxygen cutting, and arc cutting.

Work Area. That portion of a walking/working surface where job duties are being performed.

Work Area. A room or defined space in a workplace where hazardous substances are produced or used and where employees are present.

Work Practice Controls. Those controls which eliminate or reduce the hazard through changes in the work practices (i.e., rotating workers, reducing the amount of worker exposure, and housekeeping).

Work Surface. Generally a laboratory bench top or floor in the case of a walk in hood; the area under the hood where apparatus and equipment is placed. Caution must be exercised if the work surface or hood body is made of transite, an asbestos containing material.

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Zero Mechanical State. The mechanical potential energy of all portions of the machine or equipment is set so that the opening of the pipe(s), tube(s), hose(s), or actuation of any valve, lever, or button will not produce a movement which could cause injury.

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