WHMIS Symbols

Symbols are so prevalent in everyday life; it’s almost as if they’re a language in which people of any culture can understand. In fact, in many situations, this is actually the case. Think about the little “man” or “woman” symbol on the door of a public restroom and you’ll realize that most people know what they mean.

If you’ve been a worker in Canada for any length of time, it’s very likely that you’re familiar with WHMIS, and know that one of the most important elements of it is the WHMIS Symbols.

What are WHMIS Symbols?

WHMIS symbols are graphic images that vividly highlight the types of hazards present in various hazardous products. WHMIS symbols are meant to act as visual, easy-to-understand tools for helping workers to immediately identify the types of hazards present in various hazardous products, and to handle the products according to prescribed safety measures. A quick glance at a WHMIS symbol, such as flammable, corrosive or dangerously reactive, will alert the user of the hazardous product of the potential dangers and compel him/her to take the requisite precautions.

WHMIS Symbols vs. WHMIS Pictograms

In 2015, Canada adopted GHS, resulting in WHMIS 2015. In addition to several other changes, WHMIS 2015 introduced a new set of ” WHMIS symbols” called WHMIS 2015 Pictograms.

As we move through the WHMIS transition period, pictograms are becoming more common throughout workplaces. However, the 1988 WHMIS symbols are still prevalent, and employers and workers still must clearly understand what they mean.

Differences Between WHMIS 1988 Symbols and WHMIS 2015 Pictograms

  • While WHMIS symbols are denoted with symbols inside black “circled” borders, the WHMIS pictograms are denoted by symbols inside red “diamond” shaped borders
  • Some WHMIS 1988 symbols such as the “Exclamation T “(for Other Toxic Effects) and the “R” (for Dangerously Reactive) have been entirely replaced and are non-existent in WHMIS 2015
  • The red borders of WHMIS 2015 make the black symbols inside borders more prominent and visible to all users of hazardous products than the black borders with black symbols that are used in WHMIS 1988
  • WHMIS 2015 pictograms are universally accepted symbols while WHMIS 1988 are not

WHMIS Symbols & WHMIS Classification (WHMIS 1988)

According to WHMIS 1988, there are six classes of controlled products. WHMIS Symbols are required to be displayed on supplier labels of material which have features of one or more of these classes. This means that the supplier label of a hazardous material may display a single symbol, but can also display multiple symbols.

Class A Materials – Compressed Gases

compressed-gas-whmis-symbol-class-aAny material or substance under high pressure is considered a compressed gas.

Examples of Class A Materials include tanks used for cutting, welding and brazing, forklift propane cylinders and fire extinguishers. Because compressed gases are typically under high pressure, they have the ability to explode or become dangerous projectiles if they’re heated or dropped. Additionally, depending on what material is contained within a cylinder, leaks could potentially present hazards if they occur.

Class B Materials – Flammable and Combustible

These types of materials catch fire and burn easily.whmis symbols - flammable - class b

Examples of Class B Materials Include propane, paints and solvents, and certain types of fuel. The predominant hazard with materials which display this symbol is the potential for fires. Not only can fire burn you, but it can also rob a space of its critical oxygen content which you require to stay alive. These chemicals may also create vapours and fumes when burning, which may also be damaging to your health.

Class C Materials – Oxidizing

oxidizing-whmis-symbol-class-cOxidizing materials can potentially cause fires if they were to come in contact with combustible materials.

Examples of Class C Materials include oxygen, bleach, and hydrogen peroxide. The primary hazard associated with oxidizers is their ability to act as an oxygen source; therefore, they can stimulate the combustion of certain materials such as wood and paper.

Class D1 Materials – Poisonous and Infectious – Materials Causing Immediate and Serious Toxic Effects

whmis symbols - materials causing immediate and serious toxic effects - class d1These are toxic substances which can cause severe health effects such as loss of consciousness and even death within minutes after exposure.

Examples of Class D1 Materials include chlorine, cyanide, and toluene. These materials are extremely poisonous and can cause severe health effects within a very short period after exposure; sometimes immediately and other times within minutes to hours.

Class D2 Materials – Poisonous and Infectious – Materials Causing Other Toxic Effects

whmis symbols - materials causing other toxi effects - class d2The effects of exposure to chemicals within this class can range from skin and eye irritation to more serious, permanent health effects such as cancer and congenital disabilities.

Examples of Class D2 Materials include asbestos fibres, mercury, and lead. The effects of these chemicals are not always quick. Overexposure and mishandling may have severe consequences which include cancer, allergies, reproductive problems and even changes to your genes.

Class D3 Materials – Poisonous and Infectious – Biohazardous Infectious Material

whmis symbols - biohazardous infectious materials - class d3These materials are organisms or the toxins which they produce that can cause diseases in people or animals.

Biohazardous Infectious Materials can typically be found in hospitals, health care facilities, laboratories, veterinary practices and research facilities. Examples of Class D3 Materials include bacteria, parasites, and viruses. These materials are toxic and can result in serious diseases which can lead to death.

Class E Materials – Corrosive

whmis symbols - corrosive materials - class eCorrosive Materials can cause severe burns to skin and other human tissues such as the eye or lungs on contact. Additionally, some Class E materials can attack clothes and other materials including metals.

Examples of Class E Materials include sulphuric acid, sodium hydroxide, and ammonia gas. Corrosive materials have the ability to burn human tissue on contact. The effects can vary and typically range from skin irritation to severe burns, blindness, and even death. The effects of corrosive materials are generally permanent.

Class F Materials – Dangerously Reactive

whmi symbols - dangerously reactive materials - class fMaterials which fall under this classification show the following characteristics:

  • They can react very quickly with water to create a poisonous gas
  • They may react with themselves if they get bumped, shocked or heated
  • They can join to themselves vigorously, break down or lose water, allowing them to become denser

Examples of Class F Materials include organic peroxides, aluminum chloride, and styrene. Dangerously Reactive Materials are highly volatile. They can react with water to release a toxic gas or they can explode as a result of shock, heat or friction.

Employer Duties & Training

While WHMIS symbols from the 1988 system will eventually be phased out, throughout the WHMIS transition period, employers and workers will encounter WHMIS symbols from WHMIS 1988 and Pictograms from WHMIS 2015.

Employers must ensure that their workers can identify both types of images, know what they mean, and take the required safety precautions while working with or around the hazardous products that the images are displayed on.

Facilitating high-quality WHMIS training that includes elements from both systems will be required throughout the duration of the WHMIS transition period. This can be accomplished through training your workers on site with updated WHMIS training materials or through the use of high-quality online training that covers both WHMIS 1988 and WHMIS 2015.

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