The full memo can be found here: PDF – The Quarantine Act and Essential Travel

Entry into Canada

By The Quarantine Act, the Government of Canada is enforcing a 14-day mandatory quarantine period for all persons entering Canada, except if:

“You are identified as an individual who is exempted from this Order because you meet the
definition of an essential service worker.”

For Ontario, automotive manufacturing and transportation are listed as an essential service (see 23 & 21 respectively)

This provincial designation exempts employees of automotive suppliers and the transportation
employees that carry their products in and out of Canada from mandatory quarantine. However, anyone who is travelling cross-border in these endeavours are strongly encouraged to reasonably self-isolate.

View Canada Health’s guidance for more information.

Guidance on Essential Services and Functions in Canada During the COVID-19 Pandemic released by Public Safety Canada classifies “critical infrastructure” and clearly states that the authority to determine if a specific job is deemed essential falls to Provincial or Territorial government

View Public Safety Canada’s guidance for more information.

NOTE: The above relates only to entry into Canada.

The full memo can be found here: PDF – The Quarantine Act and Essential Travel