Section 3: Safety Practices

Lesson 3: Identifying Chemicals


Regardless of whether you are producing garden vegetables or large-scale farm crops, you may be using a variety of chemicals.
Some of these can be hazardous, and being aware of the type of hazard involved is essential to your proper and safe usage of them.
Fortunately, in Canada, there is a national workplace hazard communication standard to help us recognize dangerous products and instruct us how to use them safely.
This standard is known as WHMIS (Workplace Hazardous Materials Information System).
It functions by doing the following:
  • identifying hazardous materials and declaring them as controlled substances.

  • labelling each controlled product with a standardized, easily recognized symbol to indicate the type of hazard involved.

  • providing a Material Safety Data Sheet (MSDS), that gives information on safe use of the controlled product, as well as first-aid measures to be used in case of worker contact with the product.

Learning WHMIS Class Symbols


In WHMIS, products are first assessed to:
a) see if they are hazardous and to
b) identify the type of hazard.

Any product that has been assessed as hazardous is considered a "controlled product" and must become part of WHMIS. 

A controlled product is a hazardous substance that requires proper WHMIS labeling and handling practices.



 
Β©iStock
There are 10 hazard symbols that are used to identify controlled substances. 
Click on each pictogram name below to see the pictogram and a description of the hazard.

Gases under pressure (compressed gas, liquefied gas, refrigerated liquefied gas, dissolved gas)

 


  • Fire hazards
  • Flammables (gases, aerosols, liquids, solids)
  • Self-reactive substances and mixtures 
  • Pyrophoric liquids, solids, and gases
  • Self-heating substances and mixtures
  • Substances and mixtures which, in contact with water, emit flammable gases
  • Organic peroxides
 
                                               
  • May cause less serious health effects or damage to the ozone layer
  • Skin corrosion/irritation
  • Acute toxicity (harmful)
  • Serious eye damage/eye irritation
  • Respiratory or skin sensitization
  • Specific target organ toxicity
 

  • Can cause death or toxicity with short exposure to small amounts
  • Acute toxicity (severe)
 

  • Oxidizing gases
  • Oxidizing liquids
  • Oxidizing solids
 

  • Explosive
  • Self-reactive (severe)
  • Organic peroxide (severe)
 

  • Serious eye damage
  • Skin corrosion
  • Corrosive to metals
 

  • Biohazardous Infectious Materials
  • For organisms or toxins that can cause diseases in people or animals
 

  • Carcinogenicity
  • Respiratory Sensitization
  • Reproductive Toxicity
  • Specific Target Organ Toxicity
  • Germ Cell Mutagenicity
  • Aspiration Hazard
 

  • Aquatic Toxicity - may cause damage to the aquatic environment
 
Click here if you would you like a bookmark of the WHMIS Pictograms.



Continue to the next page to complete an exercise in WHMIS.