CBSA Provides Additional Guidance on Use of Non-Medical Masks for Border Crossing Thursday April 16, 2020 | Border & Customs, COVID-19, News Releases, Operations & Safety Canada Border Services Agency (CBSA) has provided the Canadian Trucking Alliance (CTA) additional guidance on the Public Health Agency of Canada’s (PHAC) directive that CBSA implement a policy, effective immediately, requiring all essential workers crossing the border to wear a non-medical mask or face covering.