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Setting Priorities - Chemical Hazard Assessment and Prioritization (CHAP)


Chemical safety within the workplace is important. However, understanding how hazardous different chemicals are can be difficult. Small and medium-sized workplaces often get much of their information on chemicals from the Safety Data Sheets (external link)  that come with each chemical. The Safety Data Sheets have information on how hazardous the chemical is, and on the correct use of the chemical.

One way of assessing and ranking chemical hazards is through ‘hazard banding’ (external link) . In this approach, the hazards associated with a chemical are allocated to different ‘hazard bands’. For example, a chemical assigned an “A” ‘hazard band’ is a ‘low’ hazard, up to an “E” ‘hazard band’, which is an ‘extremely high’ hazard. By looking at what ‘hazard band’ a chemical is allocated to, you are able to determine how hazardous the chemical is.

CHAP uses the hazard banding approach to assess chemical hazards. For CHAP, we use the term 'hazard level' (instead of 'hazard band') due to it being more easily understood by users. Our approach is designed to assist small to medium sized workplaces to:

  • Better understand (and assess) the hazards and risks associated with the chemicals they are using; and
  • Prioritize the most ‘hazardous’ or 'risky' chemicals for additional assessment of the control measures which are currently in-place.

The hazard levels used in CHAP come directly from a peer-reviewed article published in the journal Regulatory Toxicology and Pharmacology. The citation for the article is: Arnone, M., Kopposch, D., Smola, T., Gabriel, S., Verbist, K., Visser, R. Hazard banding in compliance with the new Globally Harmonised System (GHS) for use in control banding tools. Regulatory Toxicology and Pharmacology 2015; 73: 287-295. (external link) 

An important consideration is that hazard banding was designed to be used for chemicals/mixtures that lack sufficient toxicological or health data to assign exposure limits. In Ontario, where CHAP was developed, occupational exposure limits are available for only a few chemicals. CHAP helps users to understand how hazardous a chemical is, which is useful when an exposure limit is not available.

Versions of CHAP

(1) CHAP paper version: This is the original version of the CHAP tool. To use this version, users are to print and complete the forms provided.

(2) eCHAP-Basic: This is an adaptation of CHAP, created into a Microsoft Excel spreadsheet, that assesses up to 10 chemicals. It is primarily used to help new users familiarize themselves with the process of assessing chemical hazards through CHAP.

(3) eCHAP-Advanced: This is an expanded version of eCHAP-Basic. Created in Excel like eCHAP-Basic, this tool can assess an unlimited amount of chemicals. Companies and firms can assess as many chemicals as they have in their inventory using this tool. 

(4) CHAP-Risk: This is the latest CHAP tool and allows workplaces to undertake a simple risk assessment of the chemicals they use. The CHAP-Risk tool uses the 'hazard banding' approach of the other CHAP tools and adds to this exposure and risk assessment components that are based on the approach used by COSHH Essentials (external link) . The CHAP-Risk tool allows you to assess up to 10 chemicals, with the tool providing an assessment of health and safety risk to workers along with a recommended control approach based on the level of risk calculated by the tool.

Why you should use the CHAP Tools

Benefits of the CHAP tools include:

  • They help workplaces meet their WHMIS (external link)  obligations
  • Improved understanding by and communication with workers (external link)  of the hazards posed by the chemicals they use
  • Improved management of chemical hazards with a focus on improved control measures (external link)  and protection of workers
  • Easy-to-use software packages that do not require internet access
  • Results of the assessments reside on in-house computer systems and can be used to create improved chemical inventories