The Material Safety Data Sheet (MSDS) is used to communicate chemical hazard information from the manufacturer to the employee. This is the information needed to inform and train employees on the safe use of hazardous chemicals. We are required to have an MSDS for each hazardous chemical product we use and keep paper copies in the safety room.
The MSDS Form
Let’s look at the MSDS form, itself. Some of the terms in each section link to additional information. You can check out the glossary at the end for general information on terms you may not be familiar with. Important points related to each MSDS section will be shown and then an example that illustrates those points will be shown. So, let’s start the review. Each material safety data sheet must be in English (although the employer may maintain copies in other languages as well), and must contain at least the following information:
- The name, address and telephone number of the chemical manufacturer, importer, employer or other responsible party preparing or distributing the material safety data sheet, who can provide additional information on the hazardous chemical and appropriate emergency procedures, if necessary.
- The English language requirement was included to prevent importers of chemicals from supplying MSDSs in a foreign language. This requirement, however, does not prevent a chemical manufacturer/employer from translating MSDSs from English into foreign languages, in order to assist non-English speaking employees with training comprehension and hazard recognition.
MATERIAL SAFETY DATA SHEET
FISHER SCIENTIFIC
CHEMICAL DIVISION
1 REAGENT LANE
FAIR LAWN NJ 07410
(201) 796-7100EMERGENCY NUMBER: (201) 796-7100
CHEMTREC ASSISTANCE: (800) 424-9300
THE INFORMATION BELOW IS BELIEVED TO BE ACCURATE AND REPRESENTS THE BEST INFORMATION CURRENTLY AVAILABLE TO US. HOWEVER, WE MAKE NO WARRANTY OF MERCHANTABILITY OR ANY OTHER WARRANTY, EXPRESS OR IMPLIED, WITH RESPECT TO SUCH INFORMATION, AND WE ASSUME NO LIABILITY RESULTING FROM ITS USE. USERS SHOULD MAKE THEIR OWN INVESTIGATIONS TO DETERMINE THE SUITABILITY OF THE INFORMATION FOR THEIR PARTICULAR PURPOSES.
- The identity used on the label;
- If the hazardous chemical is a single substance, its chemical and common name(s);
- If the hazardous chemical is a mixture which has been tested as a whole to determine its hazards, the chemical and common name(s) of the ingredients which contribute to these known hazards, and the common name(s) of the mixture itself; or,
- If the hazardous chemical is a mixture which has not been tested as a whole, the chemical and common name(s) of all ingredients which have been determined to be health hazards, and which comprise 1% or greater of the composition (0.1% for carcinogens);
SUBSTANCE IDENTIFICATION
CAS-NUMBER: 65-85-0
SUBSTANCE: **BENZOIC ACID**
TRADE NAMES/SYNONYMS: BENZENECARBOXYLIC ACID; CARBOXYBENZENE; DRACYLIC ACID; PHENYL CARBOXYLIC ACID; PHENYLFORMIC ACID; RETARDER BA; TENN-PLAS; RETARDEX; SOLVO POWDER; SALVO LIQUID; PHENYLCARBOXYLIC ACID; BENZOATE; BENZENEMETHANOIC ACID; BENZENEFORMIC ACID; STCC 4966340; A-63; A-65; A-68; BP344; C7H6O2; ACC02720CHEMICAL FAMILY: Carboxylic acid, aromatic
MOLECULAR FORMULA: C6-H5-C-O2-H
MOLECULAR WEIGHT: 122.12
CERCLA RATINGS (SCALE 0-3): HEALTH=3 FIRE=1 REACTIVITY=0 PERSISTENCE=2NFPA RATINGS (SCALE 0-4): HEALTH=2 FIRE=1 REACTIVITY=U
COMPONENTS AND CONTAMINANTS
COMPONENT: BENZOIC ACID PERCENT: 100 CAS# 65-85-0
EXPOSURE LIMITS: No occupational exposure limits established by OSHA, ACGIH, or NIOSH.
5000 pounds CERCLA Section 103 Reportable Quantity
- Physical and chemical characteristics of the hazardous chemical (such as vapor pressure, flash point);
PHYSICAL/CHEMICAL CHARACTERISTICS
DESCRIPTION: White powder or crystals with an odor of benzoin or benzaldehyde.
BOILING POINT: 480 F (249 C)
MELTING POINT: 252 F (122 C)
SPECIFIC GRAVITY: 1.2659 @ 15 C
VAPOR PRESSURE: 1 mmHg @ 205 F
PH: 2.8 (satd solution)
SOLUBILITY IN WATER: 2.9% @ 20 C
VAPOR DENSITY: 4.2
SOLVENT SOLUBILITY: Soluble in alcohol, ether, benzene, chloroform, acetone, carbon disulfide, oil of turpentine, carbon tetrachloride, fixed and volatile oils; slightly soluble in petroleum ether, hexane.
- The physical hazards of the hazardous chemical, including the potential for fire, explosion, and reactivity;
FIRE AND EXPLOSION HAZARD DATA
FIRE AND EXPLOSION HAZARD: Slight fire hazard when exposed to heat or flame. Dust/air mixtures may be explosive above the flash point. Vapor from molten benzoic acid may form explosive mixture with air.
FLASH POINT: 250 F (121 C)
UPPER EXPLOSIVE LIMIT: 35 g/ft3 (optimum)
LOWER EXPLOSIVE LIMIT: 3 g/ft3
AUTOIGNITION TEMPERATURE: 1060 F (571 C)
FIREFIGHTING MEDIA: Dry chemical, carbon dioxide, water spray or regular foam (1990 Emergency Response Guidebook, DOT P 5800.5). For larger fires, use water spray, fog or regular foam (1990 Emergency Response Guidebook, DOT P 5800.5).
FIREFIGHTING: Move container from fire area if you can do it without risk. Do not scatter spilled material with high-pressure water streams. Dike fire-control water for later disposal (1990 Emergency Response Guidebook, DOT P 5800.5, Guide Page 31). Use water in flooding quantities as a fog; solid streams of water may be ineffective. Cool affected containers with flooding quantities of water applying water from as far a distance as possible. Avoid breathing vapors or dusts.REACTIVITY
REACTIVITY: Stable under normal temperatures and pressures.
INCOMPATIBILITIES: OXIDIZERS (STRONG): Vigorous exothermic reaction.
DECOMPOSITION: Thermal decomposition products may include toxic oxides of carbon.
POLYMERIZATION: Hazardous polymerization has not been reported to occur under normal temperatures and pressures.
- The health hazards of the hazardous chemical, including signs and symptoms of exposure, and any medical conditions which are generally recognized as being aggravated by exposure to the chemical;
- The primary route(s) of entry;
- Emergency and first aid procedures;
- The OSHA permissible exposure limit, ACGIH Threshold Limit Value, and any other exposure limit used or recommended by the chemical manufacturer, importer, or employer preparing the material safety data sheet, where available;
- Whether the hazardous chemical is listed in the National Toxicology Program (NTP) Annual Report on Carcinogens (latest edition) or has been found to be a potential carcinogen in the International Agency for Research on Cancer (IARC) Monographs (latest editions), or by OSHA;
TOXICITY
IRRITATION DATA: 22 mg/3 days intermittent skin-human moderate; 500 mg/24 hours skin-rabbit mild; 100 mg eye-rabbit severe.
TOXICITY DATA: 6 mg/kg skin-human TDLo; 500 mg/kg oral-man LDLo; 1700 mg/kg oral-rat LD50; 1940 mg/kg oral-mouse LD50; 2 gm/kg oral-guinea pig LDLo; 2000 mg/kg oral-dog LD50; 2000 mg/kg oral-cat LD50; 2000 mg/kg oral-rabbit LDLo; 2000 mg/kg subcutaneous-rabbit LDLo; 1400 mg/kg intraperitoneal-guinea pig LDLo; 1460 mg/kg intraperitoneal-mouse LD50; mutagenic data (RTECS).
CARCINOGEN STATUS: None.
LOCAL EFFECTS: Irritant – eye.
ACUTE TOXICITY LEVEL: Moderately toxic by ingestion.
TARGET EFFECTS: Poisoning may affect the respiratory and central nervous system.
HEALTH EFFECTS AND FIRST AID
INHALATION:
- ACUTE EXPOSURE – Dust may cause mild respiratory irritation with sore throat and coughing.
- CHRONIC EXPOSURE – No data available.
- FIRST AID – Remove from exposure area to fresh air immediately. If breathing has stopped, perform artificial respiration. Keep person warm and at rest. Treat symptomatically and supportively. Get medical attention immediately.
SKIN CONTACT:
- ACUTE EXPOSURE – Dust and liquid may cause mild irritation and redness. Concentrations up to 0.2%, may elicit an immediate skin reaction varying from erythema to a non-immunologic contact urticaria in some persons.
- CHRONIC EXPOSURE – Repeated application to human skin produced moderate irritation.
- FIRST AID – Remove contaminated clothing and shoes immediately. Wash affected area with soap or mild detergent and large amounts of water until no evidence of chemical remains (approximately 15-20 minutes). Get medical attention immediately.
EYE CONTACT: IRRITANT.
- ACUTE EXPOSURE – Dust may cause strong irritation and redness.
- CHRONIC EXPOSURE – Repeated or prolonged contact with irritants may cause conjunctivitis.
- FIRST AID – Wash eyes immediately with large amounts of water or normal saline, occasionally lifting upper and lower lids, until no evidence of chemical remains (approximately 15-20 minutes). Get medical attention immediately.
INGESTION:
- ACUTE EXPOSURE – Large doses may cause sore throat, gastric pain, nausea, vomiting, and possible allergic reactions. A 67 kg man ingested 50 gm without ill effects.
- CHRONIC EXPOSURE – A daily intake of 4-6 grams produced no toxic effects outside of gastric irritation. Larger doses may have systemic effects similar to salicylates and may include disturbances in acid base balance, tremor and convulsions.
- FIRST AID – Treat symptomatically and supportively. Get medical attention immediately. If vomiting occurs, keep head lower than hips to prevent aspiration.
ANTIDOTE: No specific antidote. Treat symptomatically and supportively.
- Any generally applicable precautions for safe handling and use which are known to the chemical manufacturer, importer or employer preparing the material safety data sheet, including appropriate hygienic practices, protective measures during repair and maintenance of contaminated equipment, and procedures for clean-up of spills and leaks;
STORAGE AND DISPOSAL
Observe all federal, state and local regulations when storing or disposing of this substance. Store away from incompatible substances.
CONDITIONS TO AVOID
May burn but does not ignite readily. Avoid contact with strong oxidizers, excessive heat, sparks, or open flame.
SPILL AND LEAK PROCEDURES
SOIL SPILL: Dig holding area such as lagoon, pond or pit for containment. Use protective cover such as a plastic sheet to prevent material from dissolving in fire extinguishing water or rain.
WATER SPILL: Use activated carbon to absorb spilled substance that is dissolved. Use mechanical dredges or lifts to extract immobilized masses of pollution and precipitates. Use suction hoses to remove trapped spill material.
OCCUPATIONAL SPILL: Sweep up and place in suitable clean, dry containers for reclamation or later disposal. Do not flush spilled material into sewer. Keep unnecessary people away.
Reportable Quantity (RQ): 5000 pounds
The Superfund Amendments and Reauthorization Act (SARA) Section 304 requires that a release equal to or greater than the reportable quantity for this substance be immediately reported to the local emergency planning committee and the state emergency response commission (40 CFR 355.40). If the release of this substance is reportable under CERCLA Section 103, the National Response Center must be notified immediately at (800) 424-8802 or (202) 426-2675 in the metropolitan Washington, D.C. area (40 CFR 302.6).
- Any generally applicable control measures which are known to the chemical manufacturer, importer or employer preparing the material safety data sheet, such as appropriate engineering controls, work practices, or personal protective equipment;
PROTECTIVE EQUIPMENT
VENTILATION: Provide local exhaust ventilation. Ventilation equipment should be explosion-proof if explosive concentrations of dust, vapor or fume are present.
RESPIRATOR: The following respirators are recommended based on information found in the physical data, toxicity and health effects sections. They are ranked in order from minimum to maximum respiratory protection. The specific respirator selected must be based on contamination levels found in the work place, must be based on the specific operation, must not exceed the working limits of the respirator and must be jointly approved by the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration (NIOSH-MSHA).- Any dust and mist respirator.
- Any air-purifying respirator with a high-efficiency particulate filter.
- Any powered air-purifying respirator with a dust and mist filter.
- Any powered air-purifying respirator with a high-efficiency particulate filter.
- Any type ‘C’ supplied-air respirator operated in the pressure-demand or other positive pressure or continuous-flow mode.
- Any self-contained breathing apparatus.
FOR FIREFIGHTING AND OTHER IMMEDIATELY DANGEROUS TO LIFE OR HEALTH CONDITIONS:
- Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode.
- Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive-pressure mode.
CLOTHING: Employee must wear appropriate protective (impervious) clothing and equipment to prevent repeated or prolonged skin contact with this substance.
GLOVES: Employee must wear appropriate protective gloves to prevent contact with this substance.
EYE PROTECTION: Employee must wear splash-proof or dust-resistant safety goggles to prevent eye contact with this substance.- Emergency eye wash: Where there is any possibility that an employee’s eyes may be exposed to this substance, the employer should provide an eye wash fountain within the immediate work area for emergency use.
- The date of preparation of the material safety data sheet or the last change to it.
PREPARATION DOCUMENTATION
AUTHORIZED – XYZ SCIENTIFIC GROUP, INC.
CREATION DATE: 11/02/84
REVISION DATE: 12/23/93
ADDITIONAL INFORMATION – THE INFORMATION BELOW IS BELIEVED TO BE ACCURATE AND REPRESENTS THE BEST INFORMATION CURRENTLY AVAILABLE TO US. HOWEVER, WE MAKE NO WARRANTY OF MERCHANTABILITY OR ANY OTHER WARRANTY, EXPRESS OR IMPLIED, WITH RESPECT TO SUCH INFORMATION, AND WE ASSUME NO LIABILITY RESULTING FROM ITS USE. USERS SHOULD MAKE THEIR OWN INVESTIGATIONS TO DETERMINE THE SUITABILITY OF THE INFORMATION FOR THEIR PARTICULAR PURPOSES.
If no relevant information is found for any given category on the material safety data sheet, the chemical manufacturer, importer or employer preparing the material safety data sheet must mark it to indicate that no applicable information was found.
Employer Responsibilities
Employers must maintain in the workplace copies of the required material safety data sheets for each hazardous chemical, and must ensure that they are readily accessible to employees when they are in their work area(s). (Electronic access, microfiche, and other alternatives to maintaining paper copies of the material safety data sheets are permitted as long as no barriers to immediate employee access in each workplace are created by such options.) Marshall recommends using the internet to find the necessary MSDS sheets if they are not provided in the folder of MSDSs in the lab.
However, the employer must ensure that in all cases the required information is provided for each hazardous chemical, and is readily accessible during each work to employees when they are in in their work area(s). Usually, MSDSs will be kept at the “Right to Know” station in a centralized location where most of the work is being accomplished. Along with the MSDSs, there must be a list of chemicals with an effective reference system to help the employee quickly locate a specific MSDS.
Finally, on the next page is a form for you to print out and sign signifying that you have read these modules and agree to follow the rules. You are to turn this form into the lab instructor. The chemistry department will be conducting random inspections of the labs. If it is discovered that the lab is in an unacceptable condition, the last TA to have used the lab will be required to rectify the situation.
Glossary of Terms
Acute Exposure
A short-term exposure usually occurring at high concentration.
Acute Health Effect
An effect that develops either immediately or a short time after exposure.
Antidote
A remedy or other agent to counteract the effects of a poison.
Atomic Weight
The average weight of an atom of an element, usually expressed relative to one atom of the carbon isotope taken as a weight of 12.
Autoignition Temperature
The minimum temperature required to initiate or cause self-sustained combustion, in the absence of a spark or flame.
Biohazardous Infectious Material
A material that contains organisms and the toxins produced by these organisms that have been shown to cause disease or are believed to cause disease in either humans or animals.
Boiling Point
The temperature at which a liquid changes from a liquids to a gas, at normal atmospheric pressure.
Carcinogens
Agents/compounds that may induce cancer in humans.
CAS Registry Number
A number assigned to a material by the Chemical Abstracts Service (CAS) to provide a single unique identifier.
Chemical Formula
Sometimes called the molecular formula, indicates the elements that make up a chemical.
Chemical Name
A proper scientific name for the active ingredient of a product.
Chronic Exposure
A long-term exposure, usually occurring at low concentrations.
Chronic Health Effects
An effect that appears a long time after exposure.
Coefficient of Oil/Water Distribution
Tthe ratio of the solubility of the chemical in an oil to its solubility in water.
Combustible Liquid
A liquid which has a flash point above 37.8 C.
Compressed Gas
A material which is a gas at normal room temperature (20 C) and pressure but is packaged as a pressurized gas, dissolved gas or gas liquefied by compression or refrigeration.
Condensation
The process of reducing from one form to another denser form such as steam to water.
Controlled Products
Under the Controlled Products Regulation, a controlled product is defined as a material, product or substance which is imported or sold in Canada and meets the criteria for one or more of the following classes:
- Class A – Compressed Gas
- Class B – Flammable and Combustible Material
- Class C – Oxidizing Material
- Class D – Poisonous and Infectious Material
- Class E – Corrosive Material
- Class F – Dangerously Reactive Material
Corrosive Material
A material that can attack (corrode) metals or cause permanent damage to human tissues such as skin and eyes on contact.
Cryogenics
Materials which exist at extremely low temperatures, such as liquid nitrogen.
Dangerously Reactive Materials
Materials that may undergo vigorous condensation, decomposition or polymerization. They may react violently under conditions of shock or increase in pressure or temperature. They may also react vigorously with water or water vapor to release a toxic gas.
Decomposition
The breakdown of a substance, often due to heat, decay or other effect, with the release of other compounds such as vapors or gases that may be flammable or toxic.
Density
The weight of a material in a given volume. It is usually given in grams per millilitre (g/ml).
Dilution Ventilation
Dilution of contaminated air with uncontaminated air in a general area, room or building for the purposes of health hazard or nuisance control, and/or for heating and cooling.
Dose
Amount of the agent that has entered the body through the various routes of entry.
Evaporation Rate
The rate at which a liquid changes to vapor at normal room temperature.
Explosive (Flammable) Limits
The lower explosive (flammable) limit (LEL) is the lowest concentration of vapor in air which will burn or explode upon contact with a source of ignition. The upper explosive (flammable) limit (UEL) is the highest concentration of vapor in air which will burn or explode upon contact with a source of ignition.
Explosive (Flammable) Range
The range between the lower explosive limit (LEL) and the upper explosive limit (UEL).
Exposure Limits
Established concentrations which, if not exceeded, will not generally cause adverse effects to the worker exposed. Exposure limits differ in name and meaning depending on origin. For example:
- The exposure levels for the hazardous chemicals that are included in the Regulation respecting the Control of Exposure to Biological or Chemical Agents made under the Occupational Health and Safety Act of Ontario, are expressed as follow:
- Time-Weighted Average Exposure Value (TWAEV): The average airborne concentration of a biological or chemical agent to which a worker may be exposed in a work day or a work week.
- Short Term Exposure Value (STEV): The maximum airborne concentration of a chemical or biological agent to which a worker may be exposed in any 15 minute period, provided the TWAEV is not exceeded.
- Ceiling Exposure Value (CEV):The maximum airborne concentration of a biological or chemical agent to which a worker may be exposed at any time.
- SKIN: This notation indicates that direct or airborne contact with the product may result in significant absorption of the product through the skin, mucous membranes or eyes. Inclusion of this notation is intended to suggest that preventative action be taken against absorption of the agent through these routes of entry.
- Threshold Limit Values (TLVs) are exposure guidelines developed by the American Conference of Governmental Industrial Hygienists (ACGIH). They have been adopted by several Canadian governments and others as their legal limits. They are expressed as follows:
- Threshold Limit Value – Time-Weighted Average (TLV-TWA):The time-weighted average concentration for a normal 8 hour work day and a 40 hour work week, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect.
- Threshold Limit Value – Short Term Exposure Limit (TLV-STEL): a 15 minute time-weighted average exposure which should not be exceeded at any time during a work day even if the 8 hr TWA is within the TLV. Exposures at the STEL should not be repeated more than 4 times a day and there should be at least 60 minutes between successive exposures at the STEL.
- Threshold Limit Value – Ceiling (TLV-C): the concentration that should not be exceeded during any part of the working exposure.Other exposure limits include the Permissible Exposure Limits (PEL) which are legal exposure limits in the United States.
Flammable Limits
“See Explosive Limits”.
Flammable Substance
one that will readily catch fire and continue to burn in air if exposed to a source of ignition.
- Flammable Aerosol – a material that is packaged in an aerosol container which can release a flammable material.
- Flammable Gas – a gas which can readily catch fire and continue to burn.
- Flammable Liquid – a material that gives off a vapor which can readily catch fire and continue to burn. A flammable liquid has a flashpoint below 37.8 C.
- Flammable Solid – a material which can readily catch fire and continue to burn vigorously and persistently. This may occur from friction, absorbing moisture, from spontaneous chemical change, or by retaining heat from manufacturing or processing.
- Reactive Flammable Material – a material which is a dangerous fire risk because it can react readily with air or water.
Flashback
This occurs when a trail of flammable material is ignited by a distant source of ignition. The flame then travels back along the trail of gas, vapor or aerosol to its source.
Flashpoint
The lowest temperature of a liquid at which it gives off enough vapor to form an ignitable mixture of vapor and air immediately above the liquid surface.
Freezing Point
The temperature at which a liquid becomes a solid, at normal atmospheric pressure.
Hazard
The potential for harmful effects.
Hazardous Combustion Products
Chemicals which may be formed when a material burns. These chemicals may be flammable, toxic or have other hazards.
Hazardous Decomposition Products
Formed when a material decomposes (breaks down) because it is unstable, or reacts with materials such as water or oxygen in air.
Hazardous Ingredient
Under the Hazardous Products Act, a chemical must be listed in the Hazardous Ingredients section of a MSDS if:
- it meets the criteria for a controlled product;
- it is on the Ingredient Disclosure List;
- there is no toxicological information available; or
- the supplier has reason to believe it might be hazardous.
Hazardous Polymerization
Polymerization is a process of forming a polymer by combining large numbers of chemical units or monomers into long chains (polyethylene from ethylene or polystyrene from styrene). Uncontrolled polymerization can be extremely hazardous. Some polymerization processes can release considerable heat or can be explosive.
Ingestion
Means taking a material into the body by mouth (swallowing).
Inhalation
Means taking a material into the body by breathing it in.
Irritant
Some sort of aggravation of whatever tissue the material comes in contact with.
LC50, 50% Lethal Concentration
The concentration of a material in air which causes death in 50% of a group of test animals. The material is inhaled over a set period of time, usually 4 hrs. LC stands for lethal concentration.
LD50, 50% Lethal Dose
The weight of material which causes the death in 50% of a group of test animals. It is usually expressed in weight of material per weight of test animal. LD stands for lethal dose.
LEL (Lower Explosive Limit)
See “Explosive Limits”.
Local Exhaust Ventilation
Involves the capture of pollutants at the source.
Material Causing Immediate and Serious Toxic Effects
Classified under “Poisonous and Infectious Material” as toxic or very toxic based on information such as the LD50 or LC50.
Material Causing Other Toxic Effects
Classified under “Poisonous and Infectious Material” as a material causing toxic effects such as skin or respiratory sensitization, carcinogenicity, mutagenicity, etc.
Melting Point
The temperature at which a solid material becomes a liquid.
Molecular Formula
A chemical formula that shows the number of atoms of each element in a molecule of a compound.
Molecular Weight
The sum of the atomic weights of a molecule’s constituent atoms.
Mutagen
An agent that affects the genes or cells of the exposed people in such a way that it may cause cancer in the exposed individual or an undesirable mutation to occur in some later generation.
NA (North American) Number
See “UN number”.
Odor Threshold
The airborne concentration, usually in part per million, at which an odor becomes noticeable.
Oxidizing Material
Gives up oxygen easily or can readily oxidize other materials.
Permissible Exposure Limits (PEL)
Legal limits in the U.S.A. set by the Occupational Safety and Health Administration (OSHA).
pH
A measure of the acidity or basicity (alkalinity) of a material when dissolved in water.
Polymer
A natural or man-made material formed by combining units, called monomers, into long chains.
Polymerization
A process of forming a polymer by combining large numbers of chemical units or monomers into long chains.
Parts Per Million (ppm)
Represents the concentration of gases or vapor in air. For example, 1 ppm of a gas means that 1 unit of the gas is present for every 1 million units of air.
Reactivity
Tendency to participate in chemical reactions.
Sensitization
The development, over time, of an allergic reaction to a chemical.
Solubility
The ability of a material to dissolve in water or another liquid.
Solvent
A material which is capable of dissolving another chemical.
Specific Gravity
The density of a liquid compared to the density of an equal amount of water.
Stability
The ability of a material to remain unchanged in the presence of heat, moisture or air.
Teratogen
Agents or compounds that a pregnant woman takes into her body that generate defects in the fetus.
TLV (Threshold Limit Value)
See “exposure Limits”.
Toxicity
Ability of a substance to cause harmful effects.
Trade Name
The name under which a product is commercially known.
TWA (Time-Weighted Average)
See “Exposure Limits”.
UEL (Upper Explosive Limits)
See “Explosive Limits”.
UN (United Nations) Number
A four digit number assigned to a potentially hazardous material or class of materials. UN numbers are internationally recognized and are used by fire fighter and other emergency response personnel for identification of materials during transportation emergencies. NA (North American) numbers are assigned by Transport Canada and the US Department of Transport to materials they consider hazardous and to which a UN number has not been assigned.
Vapor
A gaseous form of a material which is normally solid or liquid at room temperature and pressure.
Vapor Density
The density of a vapor compared to the density of an equal amount of air.
Vapor Pressure
The pressure of a vapor in equilibrium with its liquid or solid form.
Ventilation
The movement of air.
Volatility
The ability of a material to evaporate.