A port has installed a thermal scanner to screen departing passengers for coronavirus symptoms.
Portsmouth International Port said it was the first port in the UK to deploy the technology to detect travellers with a temperature.
The port said the camera would be available to test foot passengers on ferries and cruise ships once travel restrictions are eased.
Scientists say not all people with coronavirus have a raised temperature.
The thermal imaging camera, accurate to within 0.2C, will be offered to ferry and cruise operators to test passengers before boarding, the port said.
A high temperature would trigger an alarm and a medical team would decide whether to allow the passenger to travel.
Port director Mike Sellars said: "As we plan for recovery we felt that the scanner would bring confidence to passengers."
Brittany Ferries, which is currently only running freight services, said thermal cameras could be useful in the longer term.
However it said it did not expect to carry foot passengers initially once leisure travel resumes.
Sam Clifford, a research fellow at the London School of Hygiene and Tropical Medicine, said not all people with Covid-19 would have a raised temperature.
He said: "We need to be careful not to fool ourselves into thinking that this will catch absolutely everybody."
The World Health Organization has warned temperature screening for Covid-19 could yield false positives and is not effective for those who are asymptomatic.
The port said it did not plan to screen arrivals, but the scanner would be available for that purpose if the government required it.
Thermal scanners have already been introduced at some UK airports including Heathrow and Bournemouth.