CALGARY -- Air travellers looking to board a plane at Calgary International Airport now have the added step of a mandatory temperature screening.

The checks, done on departing passengers, are part of Transport Canada's plan to help slow the spread of COVID-19.

It applies to outbound passengers heading to Canadian airports — and to those departing Canada for international destinations.

The screening will be done as passengers pass through security.

Calgary International Airport joins Canada's three other large airports — in Montreal, Toronto and Vancouver — which have also added the measure to their screening process for departing passengers.

The temperature checks are being done on airport staff and personnel as well.

Any passenger that presents with a high temperature and without medical documentation to explain it will be not allowed to board and asked to re-book after a 14-day period.

Phase 3 of this federal program is expected to expand to 11 other Canadian cities in September.