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Health and Safety: Teaching Tools

>Chemical Hazards

Pictograms

Exploding Bomb
Flame
Flame over circle
Gas cylinder
Corrosion
Skull and crossbones
Health hazards
Exclamation Mark
Environment
Biohazardous infectious materials
Consumer Products


WHMIS (Workplace Hazardous Materials Information System) helps identify the hazards of products like chemical and infectious agents.

WHMIS groups products with similar properties or hazards into classes. The Hazardous Products Regulations specifies the criteria used to place products within each classification. WHMIS classifications are made by the manufacturer or supplier for products to be used in Canada.

Ten pictograms are used by WHMIS 2015. Pictograms are graphic images that immediately show the user of a hazardous product what type of hazard is present. With a quick glance, you can see, for example, that the product is flammable, or if it might be a health hazard.

Most pictograms have a distinctive red "square set on one of its points" border. Inside this border is a symbol that represents the potential hazard (e.g., fire, health hazard, corrosive, etc.).

Together, the symbol and the border are referred to as a pictogram. Pictograms are assigned to specific hazard classes or categories.

Important Note: A single product may belong to more than one hazard class. If this happens, the label may show more than one pictogram. Also note that a few hazard classes in WHMIS 2015 do not use pictograms. The product label and Section 2 (Hazards Identification) of the SDS still require the signal word, hazard statement(s), and other required label elements.

Exploding Bomb

exploding bomb

Because of the high risk of significant personal injury and extensive property damage for incidents involving these products, proper training and appreciation of the hazards is essential.

Products with this pictogram should only be used by individuals who are thoroughly trained and aware of the hazards and how to control them. This level of training is beyond the scope of this Kit.

What hazard classes use this pictogram?

While the explosive class has not been currently adopted by WHMIS, you may see the class identified.

The hazard categories address explosives in terms of unstable explosives; mass explosion hazard; severe projection hazard; fire, blast or projection hazard and may explode in fire.

Note that two other hazard classes use the explosive hazard pictogram.

  • The first two categories of self-reactive substances and mixtures (Type A and B) (e.g., most hazardous) will use this pictogram. Self-reactive substances are sensitive to temperature and temperature changes The hazard with these products is that heating (even slight heating), such as may occur through improper handling or storage conditions, may cause an explosion (Type A) or a fire/explosion (Type B). Handling, storage and control measures for these will be discussed in the section for the self-reactive substances class.
  • The other hazard class is organic peroxides. The first two categories under organic peroxides (Type A and B) (e.g., most hazardous) are an explosion (Type A) or a fire/explosion hazard (Type B) if heated. Organic peroxides are highly reactive and tend to ignite easily and burn rapidly. Organic peroxides are very unstable and are generally sensitive to light (e.g., have to be stored in darkness). Some are sensitive to temperature changes or friction (e.g., shaking or bumping a container that holds organic peroxide material). Organic peroxides tend to react explosively with metals. Handling, storage and control measures for these will be discussed under the organic peroxides hazard class.

Flame

Flame

What are Flammable hazards?

Flammable hazards are products that can ignite easily and burn rapidly. For a fire to occur, three elements must be together at the same time and in the right proportions: fuel, oxygen, and heat (e.g., an ignition source such as a spark). It is very important for fire prevention and when working safely with flammable products to make sure that these three elements are not present together in the right amounts at any time.

For example, vapours from a flammable liquid can mix with air and be exposed to the right amount of heat to ignite and burn. In the workplace, controlling the fuel (e.g., flammable products), keeping quantities low, and eliminating sources of ignition are the main ways that allow flammable products to be handled safely.

What hazard classes use the flame pictogram?

In most workplaces, you will see this pictogram used for the following hazard classes:

  • Flammable gases
  • Flammable aerosols
  • Flammable liquids
  • Flammable solids

There are other hazard classes that use the flammable hazard pictogram but these products are rarely used.

  • Pyrophoric liquids - these products react with air to cause a fire
  • Pyrophoric solids - these products react with air to cause a fire
  • Pyrophoric gases - these products react with air to cause a fire
  • Self-heating substances and mixtures (e.g., spontaneous combustion) - these products react with air, can self-heat and catch fire (no ignition source required)
  • Substances and mixtures which, in contact with water, emit flammable gases
    -these products react with water and release flammable gases
  • Self-reactive substances and mixtures* - these products can react strongly to conditions such as shock, pressure, temperature, light, or contact with another product
  • Organic peroxides* - very unstable and reactive products

* Note that the most hazardous categories (Types A, B) within these classes will use the explosion pictogram alone or with the flammable pictogram

Are there other hazards associated with flammable materials?

Fire and explosion are the main concerns, but other issues may be present.
If a product is classified as flammable, the supervisor and workers must understand specifics of what the hazards are and how to use it safely.

Other concerns with flammable hazards include:

  • Health hazards - Flammable products can be a health hazard (e.g., toxic, corrosive, irritant, etc.) at air concentrations well below the levels needed to be a fire hazard.
  • Accumulation of static charge - Static electricity is the electric charge generated when there is friction between two things made of different materials or substances. This charge can occur when flammable liquids are poured, pumped, filtered, agitated, stirred or flow through pipes these actions can act as an ignition source. The release of the charge can ignite flammable products.
  • Asphyxiation - The vapours from flammable liquids are usually heavier than air and will accumulate near the ground. These heavy vapours can displace the air in a space (take the place of air or oxygen), and become an asphyxiation (suffocation) hazard.
  • Toxic by-products from burning - When flammable products burn, toxic gases and vapours are produced such as carbon monoxide, hydrogen cyanide and nitrogen oxides.
  • Flashback - Since the vapour of most flammable liquids is heavier than air, the vapours can spread a considerable distance along the ground or floor and be ignited by a distant spark or flame or source of heat. Once vapours from a flammable liquid have ignited, the flames may "flash-back", meaning that the flames travel back to the container or source of the flammable liquid and an explosion or fire can result.
  • Hot work - Working with ignition sources near flammable products is known as "hot work." Welding and cutting are examples.

Key Handling Information for Flammable Products

  • Check the label and SDS for information about the hazards and the necessary precautions for the flammable product you are using.
  • Minimize the risk of fire/explosion by preventing the release of flammable products into the air.
  • Use flammable products only in well-ventilated areas.
  • Use the smallest amount of flammable product necessary for the job.
  • Eliminate ignition sources and combustible materials from the area where flammable products are used (e.g., including oily rags, cardboard boxes). Make sure that there is no smoking, hot work, or hidden sources of ignition (e.g., pilot lights in a furnace or hot water tank). Dispose of combustible material appropriately (e.g., oily rags are in approved containers).
  • Do not heat containers or cylinders containing flammable products.
  • In some cases, non-sparking ventilation systems and equipment (such as non-sparking tools) may be necessary.
  • Ground and bond containers or cylinders during transfer operations to prevent buildup of static charge. Be sure that you understand how to do this properly.
  • Use equipment designed for flammable storage - e.g., flammable storage fridge, flammable cabinets, or flammable safety cans.
  • Be aware of incompatible products such as oxidizers and avoid contact. Check the SDS for specific information and recommendations.
  • Be aware of conditions to avoid with the flammable product being used. Some products using this hazard pictogram may be reactive to air or water; others may be sensitive to temperature, pressure, friction, sunlight.
  • Avoid spilling product and contaminating your skin or clothing.
  • Keep work areas clean and tidy. Wipe up spills and keep surfaces clean to prevent contact with skin or incompatibles. Prevent accumulation of dust or other residues on ledges or other surfaces.
  • Do not smoke, eat or drink in work areas. Wash hands thoroughly after handling. Wash hands before eating, drinking, smoking or going to the toilet.
  • Remove contaminated clothing and leather shoes or boots since they can be a severe fire hazard. Wash contaminated items, where appropriate, immediately and thoroughly in water before re-wearing or discarding.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary to act:
    • Make sure that appropriate fire extinguishers are available.
    • Be aware of at least two different exit paths in the event of fire.
    • Make sure that eyewash and emergency shower are readily available in the immediate work area.
      These devices must be tested regularly.
    • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE, nonsparking tools, etc.). Avoid using combustible materials (such as paper towels or sawdust) to clean up or absorb spills.
  • If personal protective equipment (PPE) is required, the employer must make sure that workers are thoroughly trained in its selection, fit, use and maintenance. Refer to the SDS for guidance on selection.

Key Storage Information for Flammable Products

  • Keep away from incompatible materials. Check SDS for incompatibles.
  • Use equipment designed for flammable storage - e.g., flammable storage fridge, flammable cabinets, or flammable safety cans.
  • Always keep the lids on containers holding flammable products to prevent the release of vapours.
  • Store in a cool, dry, well-ventilated area, away from direct sunlight and exit paths. Post warning signs.
  • Keep away from potential ignition sources such as heat, sparks or open flames. No smoking near flammable storage.
  • Avoid storing large quantities if possible.
  • Inspect containers and storage area regularly for signs of leakage or damage. Contain spills or leaks by storing in trays made from compatible materials.
  • Ensure that appropriate firefighting and spill cleanup equipment is readily available.
  • Avoid storing flammable products in basements. Ground floor storage is preferred as it provides easier access for emergency situations.
  • Follow by-laws and regulations such as Fire Codes and health and safety regulations that apply to the workplace in your jurisdiction.

Flame over Circle

flame over circle

What are Oxidizing Hazards?

The pictogram for oxidizing products is an "o" with flames on top of it. The "o" is for oxygen and the flames show that oxidizers are significant fire hazard if they are not handled properly. There are three types of oxidizing product: oxidizing gases, oxidizing liquids and oxidizing solids.

The basic components for a fire are a source of fuel (such as combustibles), a source of oxygen, and a spark or source of ignition.

With most fires, the source of oxygen comes from the air (air has about 21% oxygen).

With oxidizers, these products readily give off oxygen or other oxidizing substances (such as bromine, chlorine, or fluorine) and this is a significant fire/explosion risk. Oxidizers do not burn by themselves but oxidizers can:

  • greatly increase the development of a fire and make it more intense (burns hotter and faster than the fire would under "normal" fire conditions),
  • cause substances that do not normally burn in air to burn rapidly,
  • cause some combustible materials to burn spontaneously without the presence of obvious ignition sources such as a spark or flame.

Examples include:

  • oxidizing gases: oxygen, ozone
  • oxidizing liquids: nitric acid, perchloric acid
  • oxidizing solids: potassium permanganate, sodium chlorite.

What hazard classes use the flame over circle pictogram?

The oxidizer hazard pictogram is used for three different oxidizer hazard classes:

  • Oxidizing liquids
  • Oxidizing solids
  • Oxidizing gases

Although the three classes of oxidizer may have different physical states, they share the characteristics of oxidizers and they all pose fire hazards if appropriate handling and storage needs are not followed.

Are there other potential hazards associated with oxidizers?

The primary hazard of oxidizing products is fire and explosion. In addition to property damage, if an oxidizer product contaminates the skin or clothing, there is a high risk of very significant personal injury in the event of a fire.

Other concerns with oxidizing hazards include:

  • Health hazards - Oxidizing products can have other hazardous properties as well so carefully read the label and SDS for other potential hazards (e.g., health, corrosivity, reactivity).
  • Incompatible materials - Oxidizers are very reactive. NEVER return unused product to the original container, even if it does not appear to be contaminated.

Key Handling Information for Oxidizers

  • Check the label and SDS for information about the hazards and necessary precautions for the oxidizing product you are using.
  • Eliminate ignition sources and combustible materials. Promptly remove combustible wastes, including wood, paper and rags, from work areas. Ensure that there is no smoking.
  • Keep away from incompatible materials - particularly greases, lubricants, cleaning solvents, paints, or thinners.
  • Keep valves and fittings free from oil and grease.
  • Use only in well-ventilated areas.
  • Keep containers tightly closed when not in use.
  • Avoid spilling product and contaminating your skin or clothing. Immediately report leaks, spills or failures of the safety equipment (e.g., ventilation system). In the event of a spill or leak, exit the area immediately.
  • Keep work areas clean and tidy. Wipe up spills and keep surfaces clean to prevent contact with skin or incompatibles. Prevent accumulation of dust or other residues on ledges or other surfaces.
  • Do not smoke, eat or drink in work areas. Wash hands thoroughly after handling. Wash hands before eating, drinking, smoking or going to the toilet.
  • Remove contaminated clothing and leather shoes or boots since they can be a severe fire hazard. Wash contaminated items, where applicable, immediately and thoroughly in water before re-wearing or discarding.
  • Maintenance personnel need to know the hazards and any special procedures and precautions needed before work begins.
  • Be very cautious about mixing oxidizers with water. Follow the chemical supplier's directions. Some oxidizers will generate large amounts of heat when they are mixed with water.
  • Never return unused product to the original container.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary.
    • Ensure that appropriate fire extinguishers are available.
    • Be aware of at least two different exit paths in the event of fire.
    • Ensure that eyewash and emergency shower are readily available in the immediate work area. These devices must be tested regularly. Follow first aid instructions listed on the SDS or label.
    • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE, nonsparking tools, etc.).
      Avoid using combustible or reactive materials (such as paper towels or sawdust) to clean up or absorb spills.
  • If personal protective equipment (PPE) is required, the employer must ensure that workers are thoroughly trained in its selection, fit, use and maintenance. Refer to the SDS for guidance on selection.
  • Fire resistant or flame retardant clothing may be required.

Key Storage Information for Oxidizers

  • Keep away from incompatible materials. Check SDS for incompatibles.
  • Store in a cool, dry, well-ventilated area and away from direct sunlight and exit paths. Post warning signs. Be aware of any other special storage conditions.
  • Keep away from potential ignition sources such as heat, sparks or open flames. No smoking near the oxidizer storage area.
  • Avoid storing large quantities if possible.
  • Inspect containers and storage area regularly for signs of leakage or damage. Contain spills or leaks by storing in trays made from compatible materials.
  • Store in containers that the supplier recommends. Normally these are the same containers in which the product was shipped.
  • Empty containers may contain hazardous residue. Store separately. Keep closed.
  • Do not use wooden pallets or other combustible pallets for storing containers of oxidizing products. Walls, floors, shelving, and fittings in storage areas should be constructed of non-combustible materials.
  • Ensure that appropriate firefighting and spill cleanup equipment is readily available.
  • Follow by-laws and regulations such as Fire Codes and health and safety regulations that apply to the workplace in your jurisdiction, including the disposal of empty containers.

Gas Cylinder

gas cylinder

What are gases under pressure?

Thousands of products are available which contain gases and mixtures of gases that are stored under pressure in cylinders.

There are four different hazard categories of gases under pressure:

  • compressed gas,
  • liquefied gas,
  • refrigerated liquefied gas, and
  • dissolved gas.

Compressed gas (Non-liquefied gas):

Non-liquefied gases are also known as compressed, pressurized or permanent gases. These gases do not become liquid when they are compressed at normal temperatures, even at very high pressures. Examples are oxygen, and nitrogen.

Liquefied gas and Refrigerated liquefied gas:

Liquefied gases are gases which can become liquids at normal temperatures when they are inside cylinders under pressure. Refrigerated liquefied gases are those gases that are made partially liquid because of its low temperature. Initially the cylinder is almost full of liquid, and gas fills the space above the liquid. As gas is removed from the cylinder, enough liquid evaporates to replace it, keeping the pressure in the cylinder constant. Examples: anhydrous ammonia, chlorine, propane, nitrous oxide and carbon dioxide

Dissolved gas:

Acetylene is the only commonly used dissolved gas. Acetylene is chemically very unstable and at atmospheric pressure, acetylene gas can explode. However, acetylene is routinely stored and used safely in cylinders because the acetylene cylinders are packed with an inert, porous filler. The filler is saturated with acetone or other suitable solvent. When acetylene gas is added to the cylinder, the gas dissolves in the acetone to create a stable solution.

What Hazard Classes Use this Pictogram?

Only Gases under pressure use this pictogram.

Are there other potential hazards associated with Gases under pressure?

There are many other hazards associated with Gases under pressure.

  • Health - Many gases under pressure have other properties such as being toxic, flammable, corrosive or reactive. If these properties meet the criteria for other classes, they will also use the hazard pictogram for that class (e.g., flammable gas).
  • All compressed gases are hazardous because of the high pressure inside the cylinder. Gas can be released deliberately by opening the cylinder valve, or accidentally from a broken or leaking valve. Even at a low pressure, gas can flow rapidly from an open or leaking cylinder. Damaged cylinders can rocket or spin out of control causing significant injury and damage. This type of incident is often caused when an uncapped or unsecured cylinder has been knocked over, breaking the cylinder valve.
  • Asphyxiation (suffocation) - Inert gases such as argon, helium, neon and nitrogen are not toxic and do not burn or explode but they can cause injury or death by asphyxiation if they displace the oxygen in a space. For example, a litre of liquid nitrogen forms 700 litres of nitrogen gas at room temperature.
  • Frostbite - Gases escaping from a cylinder may be very cold and cause frostbite. Severe frostbite can lead to serious permanent damage to unprotected skin or eyes. Some gases may be labelled as cryogenic which means the escaping gas is capable of causing frostbite.

Key Handling Information for Gases under pressure

  • Prevent the release of gas into the workplace. Use compressed gases only in well-ventilated areas. Close all valves when cylinders are not in use.
  • Use the smallest practical cylinder size for a particular job.
  • Keep away from flames and heat sources. No smoking.
  • Inspect all cylinders and valves for damage and proper labels. Make sure cylinders are not giving off odours or making hissing sounds. Never open a damaged valve.
  • Secure cylinders to a wall or rack in an upright position. Leave the cylinder cap in place until the cylinder is secured and ready for use.
  • Use the appropriate regulator. Make sure that equipment is compatible with cylinder pressure and contents. Do not use homemade adaptors or force connections between cylinder valve and gas handling equipment. Never tamper with safety devices in cylinders, valves or equipment.
  • Do not apply any lubricant, jointing compound or tape to cylinder valves, fittings or regulator threads. Keep dirt, rust, oil or grease away from all cylinders or fittings.
  • Do not drop or bang cylinders against each other. Move cylinders using a hand truck or cart designed for the purpose.
  • Maintenance personnel must be aware of the possible hazards and any special procedures and precautions before they begin to work.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary.
    • Ensure that appropriate fire extinguishers are available. Be aware of at least two different exit paths in the event of fire.
    • Ensure that eyewash and emergency shower are readily available in the immediate work area. These devices must be tested regularly
  • Avoid direct skin contact with extremely cold liquids or compressed gases escaping from the cylinder. Never wear watches, rings or bracelets because they can freeze to exposed skin if splashed by a cold gas. When using gases that are harmful by skin contact (e.g., frostbite), wear protective gloves, aprons or other clothing depending on the risk of skin contact.
  • Always wear eye protection when working with gases under pressure. Wear chemical safety goggles - safety glasses may not provide enough protection. In some cases, a faceshield will also be necessary.
  • If personal protective equipment (PPE) is required, the employer must ensure that workers are thoroughly trained in its selection, fit, use and maintenance. Refer to the SDS for guidance on selection.

Key Storage Information for Gases Under Pressure

  • Store compressed gas cylinders in cool, dry, well-ventilated areas, away from incompatible materials and ignition sources. Ensure that the storage temperature does not exceed 52°C (125°F). No smoking. Keep away from exits. Post warning signs.
  • Store compressed gas cylinders in the upright position and securely fastened in place with cylinder valve protection cap in place.
  • Avoid storing large quantities if possible. Do not keep cylinders longer than the supplier recommends.
  • Properly and promptly dispose of "empty" or unlabelled cylinders.
  • Ensure that appropriate firefighting equipment is readily available.
  • Follow by-laws and regulations such as Fire Codes and health and safety regulations that apply to the workplace in your jurisdiction.

Corrosion

corrosion

What are corrosive products?

Any product that can chemically damage or destroy steel or aluminum is considered "corrosive to metals".

This pictogram is also used to indicate two health hazard classes for products that can cause destructive, irreversible damage to the skin and eyes. The two hazard classes are:

  • Skin corrosion/irritation - Skin corrosion (Cat. 1, 1A, 1B and 1C)
  • Serious eye damage/eye irritation - Serious eye damage (Cat. 1)

Corrosive products such as strong acids and strong bases can attack (corrode) metal or our skin/eyes. Common acids include hydrochloric acid, nitric acid and sulfuric acid. Common bases are sodium hydroxide (caustic soda) and ammonia. Check the labels and read the SDS (Section 10: Stability and reactivity) for additional information.

What hazard classes use this pictogram?

This pictogram is used by the 'corrosive to metals' hazard class (physical hazard group) to indicate products that can cause corrosion or damage to metal containers and structures upon contact.

This pictogram is also used by two health hazard classes for products that can cause destructive, irreversible damage to the skin and/or eyes.

This pictogram indicates that the damage caused by exposure to the corrosive material is very significant and likely irreversible. Lower hazard categories (e.g., skin or eye damage that will heal/be reversible) for the two health classes will use the exclamation mark hazard pictogram or no pictogram in some cases.

Are there other potential hazards associated with corrosive products?

  • Containers can become weak and eventually leak or collapse, spilling the contents into the workplace. Corrosives can also damage metal equipment and building components which may lead to injuries and collapse of structures.
  • Many corrosive products, both liquid and solid, generate large amounts of heat when they are mixed with water. For example, a glass of water thrown into a bucket of concentrated sulfuric acid is converted instantly to steam which will eject the entire contents of the bucket into the air. If the corrosive requires dilution with water, always add the corrosive to water (do NOT add water to a corrosive), slowly, in small amounts, with frequent stirring. Always use cold water.
  • Corrosive products often have additional hazards such as reactivity, flammability, and toxicity.
  • Corrosives are incompatible with many other chemicals and may result in toxic or explosive products if they contact each other. The SDS for a corrosive will explain which metals or other products, such as plastics or wood, it will attack (check Section 10: Stability and reactivity). Pay attention to using the proper containers.

Key Handling Information for Corrosives

  • Understand all of the hazards associated with the product and how to use it safely. Consult the SDS for information about the hazards and necessary precautions for the corrosive product you are using.
  • Inspect containers of corrosive product for damage or leaks before handling.
  • Do not add water to corrosive product because this can cause a violent reaction. If it is absolutely necessary to mix a corrosive with water, do so slowly adding the corrosive to cold water, in small amounts, and stir frequently.
  • Prevent the release of corrosive product (dust, mist, gas or vapour) into the workplace.
  • Use corrosive product only in well-ventilated areas. Use the smallest amount necessary.
  • Dispense corrosives carefully and keep containers closed when not in use.
  • Use corrosion-resistant equipment such as pumps, scoops or shovels.
  • Use only the types of resistant containers recommended by the manufacturer or supplier.
  • Move containers of corrosive product with caution. Move large drums using drum cradles. Carboy caddies and safety bottle carriers are available for smaller, common container sizes.
  • Avoid direct contact with corrosive product. Clean up any spills and buildups of corrosives promptly and safely. Immediately report leaks, spills or failures of the safety equipment (e.g., ventilation system). In the event of a spill or leak, exit the area immediately.
  • Do not smoke, drink, chew gum or eat in areas where these products are used. Wash hands before eating, drinking, smoking or going to the toilet. Avoid touching your skin with contaminated hands. Clean your skin thoroughly at the end of the workday. Remove and clean contaminated clothing before wearing it again, or discard it.
  • Do not reuse empty containers - hazardous corrosive residue could remain inside.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary.
    • Ensure that eyewash and emergency shower are readily available in the immediate work area and know how to use them. These devices must be tested regularly.
    • Flush contaminated eyes or skin with water for at least 20-30 minutes, sometimes longer, in case of accidental contact. Call immediately for emergency medical assistance.
    • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE, non-sparking tools, etc.). Avoid using combustible or reactive materials (such as paper towels or sawdust) to clean up or absorb spills.
    • Ensure that appropriate fire extinguishers are available. Be aware of at least two different exit paths in the event of fire.
  • Wear the appropriate personal protective equipment (PPE) as specified by your employer for the job. This equipment may include respiratory protection, goggles, face shield and chemical protective clothing like an apron and gloves made from corrosion resistant material.
  • If personal protective equipment is required, the employer must ensure that workers are thoroughly trained in its selection, fit, use and maintenance.
    Refer to the SDS for guidance on selection.

Key Storage Information for Corrosives

  • Inspect containers and storage area regularly for signs of leakage or damage. Store in the original, labelled shipping container.
  • Store containers at a convenient height for handling, below eye level if possible. High shelving increases the risk of dropping containers and the severity of damage, injury and/or exposure if a fall occurs.
  • Keep the amount of these products in storage as small as possible.
  • It is good practice to use a "first in/first out" policy and to mark the date that the container was received and the date it was first opened.
  • Store in containers that the chemical supplier recommends (usually the same container in which the material was shipped).
  • Store away from incompatible materials and in a cool, dry, well-ventilated area and out of direct sunlight. Store corrosive on plastic trays. Keep away from incompatible materials. Check the SDS for specific information. Post warning signs.
  • Use proper corrosive storage cabinets for large quantities of corrosive products. These units have corrosion-resistant interiors and hardware (e.g., door hinges and shelf brackets). Flammable storage cabinets are NOT corrosion-resistant.
  • Ensure that appropriate firefighting and spill cleanup equipment is readily available.
  • Empty containers may contain hazardous residue. Store separately. Keep closed.
  • Follow by-laws and regulations such as Fire Codes and health and safety regulations that apply to the workplace in your jurisdiction.

Skull and Crossbones

skull and crossbones

What is acute toxicity?

These products are fatal, toxic or harmful if inhaled, following skin contact, or if swallowed.

Acute toxicity refers to effects occurring following skin contact or ingestion exposure to a single dose, or multiple doses given within 24 hours, or an inhalation exposure of 4 hours.

Acute toxicity could result from exposure to the product itself, or to a product that, upon contact with water, releases a gaseous substance that is able to cause acute toxicity.

Toxicity of a chemical does not change, but the risk of exposure from using it can be controlled and minimized through proper handling and storage practices.

For example: A highly toxic chemical can have a low health hazard if it is used with proper precautions and care. On the other hand, it is possible that a chemical of low toxicity may present a high health hazard if it is used inappropriately. These differences make proper handling and control measures very important.

What hazard classes use this pictogram?

The only class that uses this pictogram is acute toxicity.

There are many categories within the acute toxicity class. There are categories used to describe the different ways the product can enter the body ( e.g., oral (ingested/eaten), dermal (skin), or inhalation (breathed in).

Are there other hazards associated with acute toxicity?

  • Other health hazards - It is not uncommon for toxic products to have other health hazards associated with it besides acute toxicity.
  • A toxic product may also have other properties such as being corrosive, flammable or reactive. Always read the label and the SDS to be sure you understand what is in the product and how to work with it safely.

Key Handling Information for Acute Toxicity Hazards

  • Consult the label and SDS for information about ALL of the hazards and potential routes of exposure and be aware of the necessary precautions for the product you are using.
  • If it is not possible to eliminate the toxic product, evaluate whether it is feasible to substitute a less hazardous product (e.g., products that are acute toxicity category 3 or 4 are less toxic than acute toxicity category 1 or 2).
  • Avoid generating or releasing toxic product into the air (e.g., as vapours/ mists/aerosols/dusts). Keep containers tightly closed when not in use.
  • Reduce the amount that is used - do not stockpile.
  • Work with the smallest amount possible.
  • Use only in well-ventilated areas.
  • Maintain good housekeeping (e.g., clean surfaces, no accumulation of dust).
  • Avoid dry sweeping of solid product. Use a pre-wetting technique or vacuum equipped with high efficiency filter(s) instead.
  • Inspect containers of toxic product for damage or leaks before handling. Open containers slowly and carefully to prevent spillage and dispersal into the air.
  • Never eat, drink, smoke or chew gum in work areas where toxic products are used.
  • Wash hands regularly throughout the day, including before washroom breaks, before lunch or coffee breaks or any other instances where an employee leaves the area.
  • Report spills, leaks or problems with control measures immediately.
  • Maintenance personnel need to know about the possible hazards of the products they might be exposed to.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary.
    • Ensure that eyewash and emergency shower are readily available in the immediate work area. These devices must be tested regularly.
    • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE etc.).
    • Be aware of the typical symptoms of an overexposure and appropriate first aid procedures. Any signs of illness should be reported immediately to the supervisor.
    • Ensure that appropriate medical response is available (e.g., antidotes, copy of SDS for emergency physician, firefighter, etc)
  • If personal protective equipment (PPE) is required, the employer must ensure that workers are thoroughly trained in its selection, fit, use and maintenance. Refer to the SDS for guidance on selection. Emergency respiratory protection may be required in some situations.

Key Storage Information for Acute Toxicity Hazards

  • Store in a cool, dry, well-ventilated area, away from direct sunlight and exit paths. Post warning signs. Be aware of any other special storage conditions.
  • Avoid storing large quantities if possible.
  • Inspect containers and storage area regularly for signs of leakage or damage. Contain spills or leaks by storing in trays made from compatible materials.
  • Keep containers closed and sealed with tight-fitting lids.
  • Empty containers may contain hazardous residue. Store separately. Keep closed.
  • Store containers at a convenient height for handling, below eye level if possible. High shelving increases the risk of dropping containers and the severity of damage, injury and/or exposure if a fall occurs.
  • Ensure that appropriate firefighting and spill cleanup equipment is readily available.
  • Follow by-laws and regulations such as Fire Codes and health and safety regulations that apply to the workplace in your jurisdiction.

Health Hazard

health hazard

What types of health hazards are covered by this pictogram?

This pictogram is used for products that cause chronic health effects and those products with targeted health effects.

Chronic health effects occur from exposure to a product over a period of time, often measured in days, months or years. Long-term health effects such as carcinogenicity (cancer causing) or respiratory sensitization are included under this pictogram. In addition, this pictogram is used for products which can cause targeted health impacts on a specific organ system (such as the kidneys, nerves or liver) that develop after a single exposure or after repeated exposure.

Chronic toxicity is different than acute toxicity. Acute toxicity refers to immediate health effects as a result of exposure to a toxic product. Chronic toxic effects tend to develop over time, often as a result of long-term exposure to a particular product. As an example, smoking a single cigarette is unlikely to cause a lasting toxic effect but smoking many cigarettes over time is linked with numerous adverse health effects. Chronic toxicity can also refer to a persistent adverse health effect that occurred as a result of a short-term exposure to a toxic product. For some chronic toxicity hazards, there is no known safe amount to which a person can be exposed.

What hazard classes use this pictogram?

This pictogram is used by a number of hazard classes in the health hazard group. If you see this pictogram on a product, it indicates that regular exposure could result in serious health issues. The health impacts will not be obvious right away. Always read the SDS and compare it with the label for the product. Understand how to use the product safely. Ask questions if you are not sure.

The hazard classes that use this hazard pictogram are:

  • Respiratory or skin sensitization - Respiratory sensitizer (Category 1, 1A and 1B) - A respiratory sensitizer is a product that may at first cause a person to experience symptoms similar to a cold or allergies such as hay fever. With continued exposure, the symptoms progress and can resemble asthma with symptoms such as chest tightness, shortness of breath, difficulty breathing and/or coughing. A severe attack could result in death without proper medical attention.
  • Germ cell mutagenicity - This hazard class includes products that can cause permanent changes (mutations) to the cells that can be passed on to future generations.
  • Carcinogenicity - This hazard class includes product that can cause cancer.
  • Reproductive toxicity - This hazard class addresses products that have a negative impact on sexual function and fertility in adult males and females. It also addresses developmental toxicity in the developing fetus. There is an additional category which includes products that may impact children who are breastfeeding but the health hazard pictogram is NOT used for this category.
  • Specific Target Organ Toxicity - Single exposure (STOT - single) - This hazard class covers products that can have an impact on specific organs or systems in the body (e.g., liver, kidneys, blood) following a single exposure. Category 3 under STOT - single does not use the health hazard pictogram; instead it uses the exclamation mark. This category is for products that cause respiratory tract irritation or narcotic effects (such as drowsiness or dizziness).
  • Specific Target Organ Toxicity - Repeated exposure (STOT - repeated) - This hazard class covers products that can have an impact on specific organs or systems in the body (e.g., liver, kidneys, blood) following prolonged or repeated exposures.
  • Aspiration hazard - This hazard class is for liquids or solids that can enter the lungs, either through swallowing or from vomiting. Once the product enters the lungs, it can cause serious injury such as chemical pneumonia (which can also be fatal). The primary factor that determines the risk of aspiration is viscosity or whether the liquid is "thin" (more like water) or "thick" (more like honey). Low viscosity hydrocarbons (e.g., "thin" like turpentine and gasoline) can enter the lungs easily.

Are there other hazards associated with health hazards?

In addition to chronic toxicity hazards, remember that a product may have additional hazardous properties such as being acutely toxic (e.g., can have immediate toxic effects) or it may have other hazardous properties such as being corrosive or flammable.

ALWAYS check the product's SDS and label on the containers to ensure that you know what is being used and the full range of potential hazards associated with a product.

Key Handling Information for Health Hazard Products

  • Check the SDS for information about the hazards and necessary precautions for the product being used.
  • If it is not possible to eliminate the chronic toxicity hazard, evaluate whether it is possible to substitute with a less hazardous product.
  • Prevent uncontrolled release of the chronic toxicity hazard (e.g., dust, mist, vapour) into the air.
  • Use only in well-ventilated areas.
  • Reduce the amount that is used - do not stockpile.
  • Work with the smallest amount possible.
  • Avoid repeated or long-term skin contact with product or with contaminated equipment or surfaces.
  • Keep work surfaces clean. Wipe up spills. Prevent accumulation of dust or other forms of residue. Prevent contamination of surfaces that unprotected personnel may use.
  • Inspect all containers for damage or leaks before handling. Keep containers tightly closed when not in use or empty.
  • Do not reuse empty containers - hazardous residue could remain inside.
  • Immediately report leaks, spills or failures of the safety equipment (e.g., ventilation system). In the event of a spill or leak, exit the area immediately.
  • Never eat, drink, smoke or chew gum in work areas where chronic toxicity hazards are used.
  • Maintenance personnel need to know the possible hazards of the products they might be exposed to.
  • Wash hands regularly throughout the day, including before washroom breaks, before lunch or coffee breaks or any other instances where an employee leaves the area.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary.
    • Ensure that eyewash and emergency shower are readily available in the immediate work area. These devices must be tested regularly.
    • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE etc.).
    • Be aware of the typical symptoms of an overexposure and appropriate first aid procedures. Any signs of illness should be reported immediately to the supervisor. In event of a possible exposure, get medical attention. Symptoms can be delayed.
  • If personal protective equipment (PPE) is required, the employer must ensure that workers are thoroughly trained in its selection, fit, use and maintenance. Refer to the SDS for guidance on selection. Emergency respiratory protection may be required in some situations.

Key Storage Information for Health Hazard Products

  • Inspect containers and storage area regularly for signs of leakage or damage. Store in the original, labelled shipping container.
  • Keep amount in storage to an absolute minimum.
  • Keep products cool and dry, in a well-ventilated area and away from direct sunlight. Post warning signs. Restrict access to authorized personnel only.
  • Keep products away from incompatible materials. Check the SDS for specific information.
  • Store the product on shelves closest to floor level (avoid storage above eye level). Do not store on high cabinets or shelves.
  • Keep containers closed. Keep in closed containers with tight-fitting lids.
  • Empty containers may contain hazardous residue. Store separately. Keep closed.
  • Ensure that appropriate firefighting and spill cleanup equipment is readily available.
  • Follow by-laws and regulations such as Fire Codes and health and safety regulations that apply to the workplace in your jurisdiction.

Exclamation Mark

exclamation mark

What kind of health effects are covered by this pictogram?

This pictogram refers to health hazards such as skin irritation or sensitisation, and eye irritation.

What hazard classes use this pictogram?

The health impacts covered by this pictogram may not be obvious to the worker right away, but the effects are generally reversible and of relatively short duration with proper medical treatment (and when further exposure is prevented). Always read the SDS and compare it with the label for the product. Understand how to use the product safely. Ask questions if you are unsure.

The hazard classes that use this hazard pictogram are:

  • Respiratory or skin sensitization - Skin sensitizer (Category 1, 1A and 1B) - Skin sensitization is an allergic-type skin response involving symptoms such as itching, swelling, blisters, redness. Often an individual does not show any symptoms after the first exposure but with subsequent exposures, the skin reacts. Products such as latex (e.g., in gloves) and nickel are common skin sensitizers.
  • Specific target organ toxicity - Single exposure (Category 3) - This category includes products that can cause irritating effects on the respiratory tract (such as coughing, throat irritation).
  • Skin corrosion/irritation - Skin irritation (Category 2) - This category includes products which can cause reversible damage such as redness or inflammation after exposure.
  • Serious eye damage/eye irritation - Eye irritation (Category 2 and 2A) - This category includes irritant products causing reversible effects within 21 days of exposure, or products that are severe skin irritants.
  • Acute toxicity - Oral, Dermal, Inhalation (Category 4) - A product in this category fits the defined LD50 or LC50 values, and is used for products that are known to be harmful if swallowed, if inhaled, or when they come in contact with the skin.

Note: The exclamation mark may also be used to indicate products that contribute to the depletion of the ozone layer. Recall that classification and labelling of the environmental hazard group is not mandatory in Canada. However, suppliers may indicate these hazards on labels and SDSs if they choose to.

Are there other hazards associated with products with this pictogram?

In addition to meeting the criteria for this hazard pictogram, remember that a product may have additional hazardous properties such as being acutely toxic (e.g., can have immediate toxic effects) or it may have other hazardous properties such as being corrosive or flammable.

ALWAYS check the product's SDS and the label on the containers to ensure that you know what is being used and the full range of potential hazards associated with a product.

Key Handling Information for Products using the Exclamation Mark Pictogram

  • Check the SDS for information about the hazards and necessary precautions for the product you are using.
  • If it is not possible to eliminate the product, evaluate whether it is possible to substitute with a less hazardous product.
  • Prevent uncontrolled release (e.g., dust, mist, vapour) into the air or the environment.
  • Use in well-ventilated areas.
  • Prevent contamination of surfaces that unprotected personnel may use.
  • Avoid repeated or prolonged skin contact with product or with contaminated equipment or surfaces.
  • Keep work surfaces clean. Wipe up spills. Prevent accumulation of dust or other forms of residue.
  • Inspect all containers for damage or leaks before handling.
  • Never eat, drink, smoke or chew gum in work areas.
  • Wash hands regularly throughout the day, including before washroom breaks, before lunch or coffee breaks or any other instances where an employee leaves the area.
  • Understand and practice emergency procedures so that you know what to do if it becomes necessary.
    • Ensure that eyewash and emergency shower are readily available in the immediate work area.
      These devices must be tested regularly.
    • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE etc.).
    • Be aware of the typical symptoms of an overexposure and appropriate first aid procedures. Any signs of illness should be reported immediately to the supervisor.
  • If personal protective equipment (PPE) is required, the employer must ensure that workers are thoroughly trained in its selection, fit, use and maintenance. Refer to the SDS for guidance on selection. Emergency respiratory protection may be required in some situations.

Key Storage Information for Products using the Exclamation Mark Pictogram

  • Inspect containers and storage area regularly for signs of leakage or damage. Store in the original, labelled shipping container.
  • Keep cool and dry, in a well-ventilated area and away from direct sunlight. Keep containers closed.
  • In general, store away from process and production areas and away from incompatible materials. Check the SDS for specific information pertaining to incompatible materials and conditions to avoid.

Environment

environment

What are hazards to the environment?

This hazard pictogram is used for products that can have a negative effect on the aquatic environment.

Recall that classification and labelling of this hazard group is not mandatory in Canada. However, suppliers may indicate these hazards on labels and SDSs if they choose to.

If the product only has this pictogram, the main concern is its toxicity for aquatic life. If the material has other pictograms, it is also hazardous to humans in the workplace (e.g., physical or health hazards).

Aquatic hazards may include "acute hazards to the aquatic environment" which evaluates short-term toxic impacts on various aquatic life forms (such as fish, crustaceans, algae and aquatic plants). It also includes "long-term hazards to the aquatic environment" which evaluates long-term (chronic) negative impacts on aquatic life forms such as bioaccumulation (buildup of material in organism) and degradation (persistence, or how long it will remain in the environment). Examples of long-term impacts for the aquatic environment could include reduced spawning, genetic problems in offspring and behavioural changes.

What hazard classes use this pictogram?

This pictogram covers acute (short-term) effects and chronic (long-term) effects on aquatic life.

Key Handling and Storage for Environmental Hazards

  • Check the SDS for information about the hazards and precautions.
  • Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE, etc.). Contain spill quickly by diking with spill socks or suitable absorbent material (kitty litter, vermiculite, etc.). Do not leave spill site unattended.
  • Dispose of product as hazardous waste properly - not by flushing down the drain.
  • Prevent product from contaminating ground water, surface waters and sewer system. Protect floor drains, and cover the opening to sewer if able to do so and appropriate.
  • Store the product in a secure, dry, well-ventilated location. Storage area should have sills and prevent leaks from escaping into sewers.
  • Regularly inspect and maintain the equipment used for handling the substance.
  • Use secondary containment for containers such as drip trays to contain leaks or spills. Empty trays regularly to avoid overflow. Monitor use of product. Unexpected increased use may indicate leakage.
  • Isolate loading and unloading areas from surface water drainage systems. If not possible, protect drains using covers, sandbags, etc.
  • Be aware of applicable legislation in your jurisdiction concerning materials that are hazardous to the environment (e.g., permits). Report leaks, spills to the people responsible for handling emergencies where you work.

Biohazardous Infectious Materials

biohazardous infectious materials

What are biohazardous infectious materials?

These materials are organisms or the toxins they produce that can cause diseases in people or animals. Included in this class are bacteria, viruses, fungi and parasites. As these organisms can live in body tissues and fluids, they should be treated as toxic. Urine and feces should be treated as toxic only if they are visibly contaminated with blood.

What hazard classes use this pictogram?

Only biohazardous infectious materials use this pictogram.

Where are biohazardous infectious materials found?

Biohazardous infectious materials are usually found in a hospital, health care facility, laboratories, veterinary practices and research facilities. Workers in these places do not usually know which tissues or fluids contain dangerous organisms. For this reason, the workers assume that every sample is hazardous and proper protection is used all the time. Examples of biohazardous infectious materials include the AIDS/HIV virus, Hepatitis B and salmonella.

Materials in this class should only be used or handled by individuals who are thoroughly trained and aware of the hazards and how to control them. This level of training is beyond the scope of this course.

Consumer Products


Consumer products are chemical products sold to Canadians for general household use that have certain hazards (such as toxic, corrosive, flammable). Consumer products use different symbols than WHMIS.

Consumer product symbols are framed by one of two shapes, which signify whether it is the contents of the container or the container itself that is dangerous.


octagon

An octagon (stop sign) means the contents of the container are dangerous.

 

upside-down triangle
The upside-down triangle means that the container is dangerous.

The following table lists the types of hazards identified on consumer products.

Symbol Danger Product Examples
      Explosive
explosive
This container can explode if it is heated or punctured. Flying pieces of metal or plastic can cause serious injuries, especially to the eyes. Water repellant for shoes or boots in an aerosol container
Spray paint in an aerosol container
       Corrosive
corrosive

This product can burn skin or eyes on contact, or throat and stomach if swallowed. Toilet bowl cleaner
Oven cleaner
      Flammable
flammable

This product or its vapour, can catch fire easily if it is near heat, flames or sparks. Contact adhesives
Solvents
           Toxic
toxic

Licking, eating, drinking, or sometimes smelling, this product can cause illness or death. Windshield washer fluid
Furniture polish

Adapted from: Stay Safe - A Safety Education Guide to Household Chemical Products for Children 5 to 9 years of age. Consumer Product Safety (CPS), Health Canada. Available online at:
http://publications.gc.ca/site/eng/449934/publication.html

Below the symbol will appear a signal word. The signal words and their meaning are:

  • CAUTION means temporary injury may be frequent. Death may occur with extreme exposure.
  • DANGER means may cause temporary or permanent injury or death.
  • EXTREME DANGER means exposure to very low quantities may cause death or temporary or permanent injury.
  • The back or side label of regulated containers will always have some type of bordered area. Inside the border, you will find safety instructions, the words FIRST AID TREATMENT along with instructions in case of injury and a list of harmful substances in the product.

Example

FIRST AID TREATMENT

This product contains ammonia.

If splashed on eyes or skin, flush thoroughly with water.

If swallowed, drink 240-300 mL (8 to 10 oz.) of water.

DO NOT INDUCE VOMITING.
CALL PHYSICIAN OR POISON CONTROL CENTRE IMMEDIATELY.

Note: Consumer Products are partially covered under WHMIS — an SDS is not required, but employers must still educate employees on the hazards and safe handling procedures for these products.

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