“If a Ministry of Labour, Immigration, Training and Skills Development (MLITSD) inspector did not visit your workplace last year during the Worker Exposure to Chemical Agents or WHMIS Training campaigns, expect to get a knock on the door this year,” says Tova Larsen, Health and Safety Consultant with WSPS.

The Ministry of Labour, Immigration, Training, and Skills Development (MLITSD) has extended two occupational hygiene inspection campaigns until March 31, 2026. During these campaigns, MLITSD occupational hygienists are visiting workplaces to assess worker exposure to hazardous chemicals and worker training on the new Workplace Hazardous Materials Information System (WHMIS) requirements under the amended Hazardous Products Regulations. “These inspections are already underway,” says Tova.

Occupational disease is the leading cause of worker deaths in Ontario. According to WSIB provincial data, 69% of allowed fatality claims were due to occupational disease between 2020 and 2024. And exposure to hazardous chemicals is a known cause of occupational illness. “It would be difficult to find a workplace in Ontario that doesn’t have at least one chemical in the workplace,” says Tova, illustrating that using chemicals at work is not limited to a specific sector or type of work. “They are everywhere, and they need to be handled safely.”

What will inspectors look for?

The MLITSD inspections will focus on ensuring compliance with Ontario Regulation 833: Control of Exposure to Biological or Chemical Agents and Ontario Regulation 860: Workplace Hazardous Materials Information System under the Occupational Health and Safety Act.

Ontario Regulation 833: Control of Exposure to Biological or Chemical Agents

Under Ontario Regulation 833, every employer must take all measures reasonably necessary to protect workers from exposure to hazardous biological or chemical agents. Employers must control exposure to hazardous chemicals to ensure the occupational exposure limits (OELs) are not exceeded. “Regulation 833 contains approximately 725 Ontario-specific OELs to which employers must adhere,” says Tova.

Tova also cautions against waiting for an inspector to arrive before addressing workers’ exposure. If a workplace cannot provide adequate evidence that exposure levels are below the legislated OELs, the inspector could order the workplace to conduct occupational hygiene chemical exposure testing of the air at the company’s cost to confirm that OELs are being met.

“For example, if the last time you measured chemical exposure in your workplace was 10 years ago, that may not be considered adequate evidence. The company could be required to consult an occupational hygienist to complete air testing,” says Tova. “So, it’s in the best interest of everyone to be proactive, test the exposure levels in your workplace, implement controls, provide training, and have all the documentation ready.” This is the best way to prevent occupational illness.

Ontario Regulation 860: Workplace Hazardous Materials Information System

When it comes to Regulation 860, employers must ensure the safe handling, storage, and use of hazardous products in the workplace, and that containers entering the workplace have a label and are accompanied by a Safety Data Sheet (SDS). The MLITSD is focusing on this because we are in the middle of transitioning WHMIS to align with the seventh edition of the Globally Harmonized System (GHS). Amendments include new categories and information elements on SDSs. “So, when a chemical product comes into your workplace with a new WHMIS label, you must obtain the updated safety data sheet,” says Tova.

Suppliers must revise the label and SDS when significant changes are made to a product and provide the updated SDS to employers when the product is shipped. However, it is up to employers to ensure that all existing products have the updated label on the container and that they obtain the updated SDS. 

In addition to verifying proper WHMIS labels and SDSs, inspectors will look for evidence of updated worker training. “Once you have updated WHMIS labels and SDSs in your workplace, it triggers the need to update training. Inspectors will want to see documentation that you have provided revised training to your workers.” The goal is to ensure workers know how to handle hazardous chemicals safely.

How can employers prepare?

Start with the MLITSD Occupational Hygiene Campaigns Toolkit that WSPS developed to help guide employers. Here are five additional things employers can do to prepare.

1. Understand your legal requirements under Regulation 833 and Regulation 860.
2. Use the RACE model to recognize, assess, control and evaluate the chemical hazards in your workplace.
3. Get help if you have questions. Health and safety professionals and occupational hygienists can help your workplace develop a comprehensive hazardous chemical management program. "At WSPS, we have many free resources, including a list of Frequently Asked Questions about the inspections, as well as qualified occupational hygienists who can answer your questions and provide other services,” says Tova.
4. Have your documentation ready. Among other things, the inspector may ask for chemical inventory sheets, air assessment reports (including dates), medical surveillance, SDSs, generic and job-specific WHMIS training records.
5. Ensure a worker member of the JHSC is available to accompany the inspector. JHSC members should be knowledgeable about the company’s occupational hygiene programs. Advise them to answer questions openly and honestly. If a worker representative from the JHSC is not available, another worker will be asked to join them on the inspection.

How WSPS can help 

Free resources and support

• Preparing for a Ministry of Labour, Immigration, Training and Skills Development Inspection
• What to expect when a Ministry inspector comes to your workplace (article)
• Quick Safety Tips: WHMIS (video series)
• How to read a WHMIS Safety Data Sheet (guide)
• WHMIS Regulation 860 and 833 Compliance Checklist
• Workbook for Designated Substance Assessments
• Silica in the Workplace (guide)
• Chemical Safety for Small Business (video)
• WHMIS – Hazardous Products Regulation (HPR) Amendment (guide)

Free webinars: Safety Connections

• Keeping Workers Safe Step by Step – live, May 21st, 2025
• Burning Questions: Managing Flammable & Combustible Liquids – live, June 3, 2025
• Health and Safety by Design: Respiratory Protection and Chemical Management – live June 10, 2025
• Safety Connection: Air Assessments – What are they & MLITSD Campaign Compliance (pre-recorded)
• Burning Questions: Managing Flammable & Combustible Liquid (pre-recorded)

Consulting

Contact WSPS occupational hygiene consultants to conduct air sampling and assist with your respirator protection program development to ensure you are compliant with the legislation.

Training

• Designated Substances Awareness (eCourse, 1.5 hours)
• WHMIS Training for Workers (Instructor-led, 3.5 hours)
• WHMIS Awareness for Agriculture (2 hours)
• WHMIS Online Training (eCourse, 1.5 hours)
• Compressed Gases (eCourse, 1.5 hours)

The information in this article is accurate as of its publication date.