Follow the steps to complete the form with confidence.

1. Click the ‘Get Form’ button to obtain the form and open it in the online editor.
2. Begin completing the form by entering the employer's information, including the name, firm number, class/subclass, NAICS code, and the addresses for correspondence and location of the incident.
3. Describe the nature of the business and list all workers involved in the exposure incident. Make sure to provide details such as last name, given name, date of birth, date of hire, address, telephone number, and social insurance number for each worker.
4. Proceed to the details of the incident section. Select whether the exposure was to infectious substances (Section A) or chemical/other substances (Section B) by checking the appropriate box.
5. In Section A, enter the date and time of exposure and choose the type of exposure involved. Indicate the source of exposure and specify any infectious substances suspected.
6. In Section B, similarly enter the date and time of exposure, and provide a detailed account of what occurred, including any leaks, spills, or explosions. Describe the chemical or substance involved and any protective measures or emergency measures taken.
7. Answer the questions concerning any WSIB claims related to the incident, and if applicable, provide details about formal reports made to the Ministry of Labour or Ministry of the Environment.
8. Complete the report by including the name of the person completing it, their official title, and signature. Enter a telephone number and the date of filling out the form.
9. Once all sections are complete, save your changes, and you can then download, print, or share the completed form.

Complete the Canada WSIB 3959a form online today to ensure accurate reporting of workplace exposure incidents.