Glossary of Terms

AABA (Ambient Air Breathing Apparatus): Low pressure (<15 psi) ambient air pump that supplies air from the surrounding area to workers in another location.
AC (Alternating Current): An electrical current that travels in a circuit. Usually provided through electrical outlets.
Acetate: Scratch resistant material used for faceshields that protects against chemical splash and light impact.
ACFM: Actual cubic feet per minute.
Acid: Reacts with an alkali to form a salt. Can cause skin, eye, and lung irritation.
ADA: Americans with Disabilities Act.
Aerated: To supply or impregnate with air. Allows water to "bubble" at the face rather than "hit" it. Covers face and eyes more thoroughly than non-aerated water which will "bounce" off of the face.
Agrochemical: A chemical used in agriculture, such as a pesticide or a fertilizer.
Alkali: Compound that has the ability to neutralize an acid and form a salt.
Alloy: A metal made by combining two or more metallic elements.
Ambient: The surrounding atmosphere.
Amp Probe: Meter which allows for the measurement of large amounts of current without breaking the circuit. Clamps around a conductor.
Amperage (AMP): The strength of an electric current as measured in amperes.
Ampere: Also referred to as "amp." Unit of measure applied to the flow of a charge in a conductor.
ANSI (American National Standards Institute): Private organization that provides the standards that manufacturers need to comply with.
APR (Air Purifying Respirator): Mask that pulls air through cartridges as you breathe.
Arc Rating: The maximum incident energy resistance demonstrated by a material (or a layered system of materials) prior to break open, or at the onset of a second-degree skin burn. Arc rating is normally expressed in cal/cm₂.
Arimid: Flame-retardant fiber.
Arresting Force: Force transmitted by the body when a fall is arrested.
ASME: American Society of Mechanical Engineers.
ASTM (American Society for Testing and Materials): Technical organization which develops standards on characteristics and performance of materials, products, systems, and services.
ATPV (Arc Thermal Performance Value): Expressed in cal/cm₂. Also called arc rating.
Attenuation: Reduction, expressed in decibels, of the sound intensity at a first location as compared with sound intensity at a second location.
AWS: American Welding Society.

Base: See alkali.
Becket: A loop or similar device for securing loose items on a ship.
Belly Split Leather: Most economical leather. Least consistent texture and appearance.
Bi-metal: Steel used in making blades. Comprised of a high carbon steel (flexible) backing with an HSS (hard and durable) edge welded to it. Blade's cutting teeth are ground into the HSS edge.
Biohazard: Infectious agents presenting a potential risk to a person's well-being.
Bloodborne Pathogen: Virus or infection, such as Hepatitis B or HIV, that is present in blood and can be transmitted through blood or bodily secretions.
Body Harness: Distributes the arresting forces over the thighs, shoulders, and pelvis, and can be attached to a lanyard, lifeline, or deceleration device.
Bonding: Interconnecting of two objects with clamps and bare wire. Helps prevent static sparks that could ignite flammable materials.
Bound Seam: Clean-finished chainstitch binding, which encapsulates raw edges of fabric. For intermediate levels of protection.
BPM: Blows per minute.
Breakthrough Time: Time from initial chemical contact to detection.
BTU: British thermal unit.
Butyl: Synthetic rubber which provides the highest permeation resistance to gases and water vapors. Does not offer the physical strength of natural rubber.

Cal (Calorie): A unit of thermal energy.
Capacitance: The ratio of charge to potential on an electrically charged, isolated conductor.
Capacitor: Fundamental electrical device capable of storing an electrical charge.
Carabiner: Self-closing, self-locking steel connector used to attach to an anchorage point.
Carbide Steel: Very hard steel known for its ability to maintain a sharp cutting edge under hard use.
CarbonX: Flame-resistant material.
Case Hardened Finish: Finish manufactured into a glove which repels chemicals and makes donning and doffing easy.
Caustic: Strongly irritates, burns, corrodes, or destroys living tissue.
CBRN: Chemical, biological, radiological, nuclear.
CFM: Cubic feet per minute.
CFR: Code of Federal Regulations.
Chlorinated Finish: Finish on gloves which ensures easy donning and doffing and provides extra chemical and abrasion resistance.
"CLASS A" Fire: Wood, paper, cloth, trash, or other ordinary materials.
"CLASS B" Fire: Gasoline, grease, oil, paint, or other flammable liquids.
"CLASS C" Fire: Live electrical equipment.
"CLASS D" Fire: Flammable metals.
Class I, Division I: Where igntiable concentrations of flammable gases, vapors, or liquids can exist all of the time or some of the time under normal operating conditions.
Class I, Division II: Where igntiable concentrations of flammable gases, vapors, or liquids are not likely to exist under normal operating conditions.
Clute Pattern: Cut and sewn glove pattern featuring a straight thumb, and seams on the back of the hand.
CO: Carbon Monoxide.
Cobalt Steel: Hard steel often used in drill bits. Maintains sharp edge under pressure and heat build-up.
Collet: Non-adjustable bit holder found on rotary tools and routers.
Combustible Liquid: Burns at a flash point between 100°F and 200°F.
Concave: Having an outline or surface that curves inward like the interior of a circle or sphere.
Continuity Test: Digital multimeter (DMM) function which indicates audibly or visually that a complete circuit has been made.
Continuous Flow: Respirator system where air is continuously supplied to a mask or hood. Used where air supply capacity is not a problem.
Cordura®: Dense, tightly woven nylon fabric. Very durable.
Corrosive: Substance (such as acid) that "eats away" or gradually weakens something.
Corrugated: Material, surface, or structure shaped into alternate ridges and grooves.
Counts: Potential number which a DMM is capable of displaying. For example, 4-digit DMMs display 10,000 counts; 0-9999 and any number in between.
CSA: Canadian Standards Association.
Current: Free flow of electrons in a conductor.

dB (Decibel): Unit that expresses the relative intensity of sounds on a scale of 0 (least perceptible) to 130 (pain level).
DC (Direct Current): Electric current that travels in one direction. Usually supplied by batteries or a transformer that changes a current from AC to DC.
Degradation: Change in physical properties due to erosion from chemicals.
Dexterity: The ability to feel through gloves.
Dielectric: Material that doesn't conduct or transfer a direct electric current.
Digital Multimeter (DMM): Meter which displays the measurement in numerical form via an LCD or LED display.
Direct Venting: Series of holes on a goggle that allows direct air flow to the space behind the lenses. Shouldn't be used for splash because these vents will allow fluid through.
DMM: Digital multimeter.
Doff: To take something off.
Donn: To put something on.
DOT: Department of Transportation.
Double-Insulated: Provides electric shock protection through the use of two separate systems of electrical insulation.
Duck Cuff: Economical, single ply cotton added for durability.
Duct: A channel or tube for conveying something.
Duty-Cycle: Percentage of a 10-minute period that a welder can operate at a specified output before it needs to have a cool-down cycle.

EH: Electrical hazard.
Elastomer: A natural or synthetic polymer having elastic properties.
Electric Arc: Electrical conduction through a gas in an applied electric field.
Electrolytes
EMS: Emergency Medical Services.; Essential salts and minerals contained in bodily fluids.
EPA (Environmental Protection Agency): Federal agency with environmental protection, regulatory, and enforcement authority.
EPDM: Ethylene propylene diene monomer.
ESD: Electro-static dissipative.
Etchants: An acid or corrosive chemical used in etching.
Exposure Level: Level or concentration of a physical or chemical hazard to which a person is exposed.

Farad

Electrical unit of measure indicating a capacitor's ability to store a charge.

FCC

Federal Communications Commission.

FDA (Food and Drug Administration)

Responsible for ensuring that foods, drugs, biological products, medical devices, and cosmetics are safe, and accurately and informatively represented.

FHWA

Federal Highway Administration.

Filter Holder

Base plate that a prefilter would be placed on. Needed when not using a cartridge in conjunction with the prefilter. If using a cartridge then the cartridge will act as the "holder".

Filter Retainer

Top piece that holds the prefilter onto a cartridge or filter holder.

Fit Test

See Qualitative or Quantitative Fit Test. Required by OSHA. Must be satisfactorily completed before a respirator is worn in a contaminated area.

Irritant Smoke - Used on P100 filters only.
Saccharin - Used on particulate filters only.
Banana Oil - Used on organic vapor cartridges only.

Flame Arrester

Screen found inside the spout of a safety can to prevent fire flashback to the can contents.

Flame Resistant

Textiles or leather goods that naturally resist burning.

Flame Retardant

A textile that has been chemically treated to resist burning and is self-extinguishing when the source of ignition is removed.

Flash Point

Lowest temperature at which something will ignite.

Flock Lined

Shredded fiber, usually cotton, applied to the inside surface of a glove. Helps absorb perspiration and aids in donning and doffing.

FM (Factory Mutual)

Nationally recognized testing laboratory and approval service recognized by OSHA.

FPS

Feet per second.

FPT

Female pipe thread.

Fume

Solid particles of extremely small size, created when solid materials vaporize under high heat and then cool. Produced from operations such as welding, smelting, and pouring molten metal.

Gauntlet: Glove cuff 4" or more in length which gets wider towards the end.
GFCI (Ground Fault Circuit Interrupter): Device that provides protection for people and equipment from ground faults or sudden equipment restarts after a power failure.
GMAW: Gas metal arc welding (MIG).
GPH: Gallons per hour.
GPM: Gallons per minute.
Grain Leather: Smooth external side of the hide. Provides durability and dexterity.
Grommets: An eyelet placed in a hole in a sheet or panel to protect or insulate a rope or cable passed through it or to prevent the sheet or panel from being torn.
Gunn Pattern: Glove pattern featuring a wing thumb, welted seams, full leather index finger, finger tips, and knuckle straps.

H₂S: Hydrogen Sulfide.
Halogen: Light bulb which is brighter than fluorescent and krypton.
Hasp: Lockout device designed to prevent accidental equipment start-up.
HEPA (High Efficiency Particulate Air Filter): At least 99.97% efficient against particulates.
Hertz (Hz): Unit of measurement equal to one cycle per second.
HP: Horsepower.
HVAC: Heating, ventilation, and air conditioning.

IBC: Intermediate bulk container/containment.
ID: Inner diameter.
IDLH (Immediately Dangerous to Life and Health): The maximum concentration of a chemical in the air to which one can be exposed without suffering irreversible health effects.
Impedance: Found in complex AC circuits. Similar to resistance. Made up of resistance, frequency, and either capacitance or inductance.
Impregnated: Filled or saturated with a substance.
Incandescent: Luminous light with intense heat.
Indirect Venting: Allows only air through, not liquid or particles. Commonly used in chemical applications.
Inductance: Circuit element, usually a conducting coil, in which electromagnetic induction generates electromotive force.
Injection Molded: When material is introduced into a mold to form a product.
Intrinsically Safe: Product that won't cause spark in an explosive environment.
Inverter Welder: Semi-conductor circuitry boosts input frequency to 20,000-100,000 Hz reducing the need for a large heavy transformer.
IPM: Impacts per minute.
IPS: Iron Pipe Standard (pipe thread specification).
IrDA: Infrared Data Association.
ISEA: International Society of Exposure Limit.
ISO: International Organization for Standardization.
Isopropanol: A liquid alcohol, used as a solvent and in the industrial production of acetone.
Isotonic: Buffered to the same pH balance as the human eye.

Jersey: Knitted material that is extremely soft and comfortable to wear.
Joule: Unit of energy used in describing a single pulse output of a laser.

Kevlar: Cut-resistant, flame retardant fiber offers heat resistance and is often used in clothing.
Keystone Thumb: Flexible, ergonomic thumb design that is stiched directly to the palm of a glove.
Knitwrist: Knitted wristband prevents glove from falling off and debris from entering. Also keeps hands warmer.
KW: Kilowatt.

Lanyard: Flexible line used to secure a body harness to a lifeline or anchorage point.
LCD: Liquid crystal display.
LED (Light Emitting Diode): Electrical device used as an indicator light. Modern LEDs provide a very bright light and are used in flashlights, task lights, and environmental lighting.
LEL (Lowest Explosive Level): Minimum percent of a combustible gas that could cause an explosion if exposed to any source of ignition.
Level A clothing: Should be worn when the highest level of respiratory, skin, and eye protection is needed.
Level B clothing: Should be worn when the highest level of respiratory protection is needed, but a lesser level of skin protection.
Level C clothing: Should be worn when using air purifying respirators.
Level D clothing: Should be worn only as a work uniform and not on any site with respiratory or skin hazards.
Lexan®: Clear material used for faceshields. Impact and high heat resistant – up to 380°F.
Lifeline: Line provided for direct or indirect attachment to a worker's body harness, lanyard, or deceleration device. Good for horizontal or vertical applications.
Lined Glove: Supported glove which provides reinforced wear, comfort, insulation, and added resistance to abrasion, cuts, snags, and punctures.
LOTO: Lockout tagout.
Low Emulsifying Wash: Allows oils to be easily separated and collected from discharge wash water for recycling.
LP: Liquid propane.
Lumbar: The lower back.

Manual Ranging: A DMM which requires physical selection of different range settings for varying measurement inputs.
Matte: Dull and flat, without shine.
Metatarsal: Top part of the foot above the toes and below the shin bone.
Microfiber: Type of fabric created with fibers that are thousands of times smaller than fibers in conventional fabrics. Provides exceptional pick-up ability.
Micron: Unit of measure for particle size. The smaller the number, the smaller the particle.
Microprocessor: Computer on a chip. Selects ranges in auto-ranging meters and calculates true RMS voltages.
Mid-Sole: Protective sole, usually made of steel, that protects the underside of the foot against punctures resulting from stepping on sharp objects.
MIG: Metal inert gas.
Mil: Millimeter, 1/1000 of an inch.
MPT: Male pipe thread.
MSHA: Mine Safety and Health Administration.
MSDS (Material Safety Data Sheet): Contains descriptive information on hazardous chemicals under OSHA's Hazard Communication Standard. Provides precautionary information on the safe handling of the chemical, as well as emergency and first aid procedures.
MUTCD (Manual on Uniform Traffic Control Devices): Defines the standards used by road managers nationwide to install and maintain traffic control devices on all streets and highways.

Nebulizer: Hand-held ball that produces a mist or cloud when squeezed. Used in fit testing applications.
Neck Gaiter: An article of clothing worn around the neck for warmth. It is a closed tube of fabric.
Negative Pressure: Respirators that depend on wearer's lung power to draw air through filter material.
NEMA: National Electrical Manufacturers Association.
Neoprene: Synthetic rubber that is lightweight and flexible even in temperature extremes. Has a wide range of chemical and abrasion resistance.
NFPA: National Fire Protection Association.
NFPA 70E (National Fire Protection Association 70E): The standard for electrical safety in the workplace.
NG: Natural gas.
NiCad: Nickel cadmium battery.
NiMH: Nickel metal hydride battery.
NIOSH (National Institute for Occupational Safety and Health): Independent federal agency which tests and certifies respirators.
Nitrile: Synthetic rubber resists a wide range of chemicals, as well as punctures, cuts, snags, and abrasions.
Nomex® IIIA: DuPont™ flame retardant fabric woven into many materials.
Nose Cup: Part of a full face respirator that is designed to reduce fogging.
NPT: National pipe thread.
NPTF: National pipe thread female.
NPTM: National pipe thread male.
NRR (Noise Reduction Rating): The number of decibels by which the surrounding noise level is reduced.
Nuisance Level: Air concentration of a chemical below OSHA's permissible exposure limit.
Nylon: A tough, stretchable synthetic material.

O₂: Oxygen.
OD: Outside diameter.
Odor Threshold: Lowest concentration at which a substance can be detected by smell.
Ohm: Unit of measure for resistance. Also, the unit of measure for impedance.
Olefin: Synthetic fiber similar to propylene or ethylene.
OPM: Orbits per minute.
OSHA (Occupational Safety and Health Administration): Oversees and regulates workplace health and safety.
Ozone: A form of oxygen that is an irritating, sharp-smelling gas. Prevalent when striking an arc while welding on aluminum, galvanized or stainless steel.

PAPR (Powered Air Purifying Respirator): Respirator system that uses a blower motor to pull in air and distribute it through a hose to a facepiece.
Particulate: Tiny pieces of dry or liquid matter (i.e. dust, mist, fume, smoke).
Patella: The kneecap.
PEL (Permissible Exposure Limit): OSHA designated exposure limits to particles or gases.
Permeation: When a chemical penetrates through a protective material.
PETG (Polyethylene Terephthalate Glycol): Material used for chemical and light impact protection.
pH: A measure of the acidity or alkalinity of a substance on a scale of 0-14, where 7 is neutral. Less than 7 is acid. Greater than 7 is alkali.
Phenolic Wheel: Made from macerated canvas and resin. Resists shock, abrasion, and most oil and acids.
Plexiglas™: Material used to protect against impact and high heat – up to 300°F.
Pneumatic: Air operated; used with air.
Pneumatic Wheel: Tube-type inflated tire with sawtooth tread pattern for better traction on wet surfaces.
Polycarbonate: Extremely impact resistant material that blocks out 99.9% of UV rays.
Polyethylene: Non-woven, lightweight plastic material that resists chemicals and moisture.
Polypropylene: Breathable, non-woven, lightweight thermoplastic material.
Positive Pressure: Refers to respirators in which air is delivered by either pump, compressor, tank, or through a motor blower. Maintains a constant flow of clean air and prevents contaminants from entering.
PPM (Parts Per Million): Measures very low concentrations or contamination levels.
Prefilter: Used on air purifying respirators. Prefilter traps particles and helps prolong the life of the cartridge. May also be used without a cartridge.
Pressure Demand: A positive pressure respirator that regulates air flow only when a person breathes. Conserves limited air supplies.
Propionate: Provides excellent abrasion resistance and limited chemical resistance.
Prusik: A friction knot used for looping a cord around a rope. Allows movement up or down a rope, tightening when weight is applied and loosening when it is removed, letting the cord move along the rope.
PSA: Pressure sensitive adhesive.
PSI (Pounds per Square Inch): Measurement of pressure exerted by a solid, liquid, or gas.
PSIG: Pounds per square inch gauge.
PVC (Polyvinyl Chloride): Synthetic, abrasion resistant material that protects against most acids, oils, fats, caustics, and petroleum hydrocarbons. Also commonly used in drain pipes.

Qualitative Fit Testing: Tests the integrity of respirator's seal by determining if worker can smell or taste a test agent such as saccharin, banana oil, or smoke.
Quantitative Fit Testing: Respirator is worn in a test atmosphere inside a booth while instrumentation measures any leakage into the respirator.

Ratchet Suspension: A type of hard hat suspension that uses a ratcheting knob on the back strap of a hard hat suspension to either tighten or loosen the fit.
Rebar: Steel concrete reinforcement bars.
Resistance: Measure of the opposition to current flow through a component. Typically associated with resistors.
Resistor: Fundamental electronic component which will resist voltage.
Resolution: The smallest unit of measure which a DMM (Digital Multimeter) can display.
Retainer: Plastic ring that holds a cartridge or filter on a respirator.
RFI: Radio frequency interference.
RMS (Root Means Square): Formula used to calculate electronic signals. True RMS meters are highly accurate.
Rolled Cuff: Provides additional cuff strength.
Rope Grab: Device which attaches to a lifeline and provides a means of arresting a fall.
RPM: Revolutions per minute.
Rubber: Offers excellent abrasion, cut, tear, and temperature resistance, as well as great grip. Has poor flame resistance.
Rubberized Cuff: Rubber cement applied for added stiffness and durability.

Safety Cuff: Loose fitting, 2 1/2" cuff allows glove to slip off if it becomes entangled.
SCBA (Self Contained Breathing Apparatus): Supplied air system in which the air is supplied from a tank carried by the user.
Sealed Seam: Produced when materials are lapped and then thermally welded to produce a strong, tear resistant seam. There are no fillers, sealants, bindings, thread, or needle holes.
SEI: Safety Equipment Institute.
Self-Retracting Lifeline (SRL): Decelerating device which allows freedom of movement. Extends and retracts with the worker.
Semi-Pneumatic Wheel: Solid, cushioned tires made from a rubber compound. Impact-resistant and puncture-proof.
Serged Seam: Has 3 threads interlocked around the raw edges of material. For low hazard protective clothing.
SFPM: Surface feet per minute applies to band saw blade speed.
Shade #: Refers to a lens which intercepts rays of light. Different shade #'s are used in applications such as welding.
Shank: Provides extra arch support in shoes and boots.
Shirred: Gather by means of drawn or elasticized threads in parallel rows.
Shock Absorber: Allows dissipation of energy by extending the deceleration distance to reduce the fall arrest force.
Shoulder Split Leather: More economical than side split. Visible texture difference.
Side Split Leather: Most durable split leather. Provides the greatest protection.
Silicone: Provides flexibility, resiliency, and tensile strength over a wide temperature range.
Sine Wave: An alternating, repetitive waveform going both positive and negative with equal amplitude on both sides of the zero reference line.
Single-Stage Compressor: Compression takes place in one step. Typical operating range of 80-100 psi.
SMS: Spun bond, melt-blown, spun bond polypropylene material which provides a fluid and particulate barrier to protect workers. SMS fabric is lightweight, strong, breathable, durable, soft, and resistant to tears and punctures.
Snap Hook: Self-closing, self-locking device which remains closed until manually opened. Most commonly found on lanyards and used to connect to body harness and an anchorage point.
Spectacle Kit: Allows worker's eyeglass prescription to be incorporated into a full face respirator.
Spectra: Strongest cut and burn resistant fiber available.
SPM: Strokes per minute.
Starched Cuff: Starched for added durability.
STEL: Short term exposure limit.
Straight Cuff: Provides a snug fit and protects skin from chemical run-off.
Strapped Seam: Strong, gas-tight seam produced by covering the seam with a strip of material.
Supported Glove: Has a cloth liner for added comfort, support, and wear.

Taper: Diminish or reduce in thickness toward one end.
Tensile Strength: The greatest amount of stress a substance can bear without tearing.
Terrycloth: Cotton fabric material in which the fabric strands are looped in or out. Offers good heat resistance.
Thermoplastic: Plastic substances that become pliable when heated and harden when cooled.
Tie-Off: Connect to an anchorage point.
Tie-Off Strap: A polyester or nylon strap used as a temporary means of connection to an anchorage point.
TIG: Tungsten inert gas.
TLV (Threshold Limit Value): An estimate of the average safe airborne concentration of a substance that workers may be exposed to day after day without adverse effect.
Torque: The capability of a force to produce torsion or rotation on its axis.
TPP: Thermal protective performance.
TSR (Traffic Signal Recognition): ANSI standard that states a colored lens must not change the natural color of what the eye sees.
TWA: Time-weighted average.
Two-Stage Compressor: Two-step compression. Air from first compression is cooled then compressed again. Typical operating range 140-175 psi.
Type 1 Safety Can: Dispense and fill from a single opening.
Type 2 Safety Can: Has fixed nozzle and separate openings for dispensing and filling for a higher level of safety.

UFC: Uniform Fire Code.
UHF: Ultra high frequency.
UL (Underwriters Laboratories): An independent organization which operates laboratories to investigate devices and materials for potential hazards.
UNDOT: United Nations Department of Transportation.
Unsupported Glove: Gloves without any type of lining.
USCG: United States Coast Guard.
USDA (United States Department of Agriculture): Monitors and inspects meat and poultry facilities for proper handling and packaging.
UV: Ultra violet.
Uvextreme®: Anti-fog, anti-static, and anti-scratch eyewear lens coating by Uvex.

VAC: Volts alternating current.
Vapor: Gaseous form of substances which are normally in the solid or liquid state at room temperature and pressure.
VDC: Volts direct current.
Vermilion: Red lens especially for indoor use to enhance contrast. Protects from fluorescent and halogen light glare.
VHF: Very high frequency.
Vinyl: Abrasion resistant, synthetic polymer that resists most acids, oils, fats, caustics, and petroleum hydrocarbons.
Viscous: Thick flowing liquid.
Viton: Most chemical resistant of all the rubbers. Protects against PCBs and most solvents. Offers excellent resistance to gas and water vapors, but offers minimal resistance to cuts or abrasion.
VOC: Volatile organic compound.
Volatile: Easily becoming a vapor at a fairly low temperature.
Volt: Unit of electrical measure.
VOX: Voice activation (hands-free use).
VSR: Variable speed reverse.

Watts: Metric unit of power equal to the work done at the rate of one joule per second.
Welted Seam: Extra material added to reinforce and increase durability. Reduces the chance of burn-through.
Winch: Fall protection device used in raising and lowering operations. Has independent braking systems and a maximum capacity of 350 lbs.

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