Lorry drivers from across the South East took part in a protest over working hours on Friday.
Protesters also want better roadside toilets and sleeping facilities
The Transport and General Workers Union (T&G) organised a rally and leaflet handout at the entrance to the Port of Dover in Kent.
The union is calling for an end to what it calls a "long hours culture", as well as better pay and pensions.
It said drivers tired from long working hours were "more of a killer on the roads than drunk drivers".
According to T&G national secretary for transport Ron Webb, loopholes in the European Working Time Directive meant some lorry drivers were still being asked to work more than the recommended 48-hour week.
"This union remains convinced that a shorter working week, properly recognised by all not some employers, is the best way to really start reducing deaths on the road.
"All the surveys and reports I've ever seen show that drivers working long hours behind the wheel put them and other road users at an increased risk of a fatal or other serious accident.
"We want workers working 48 hours with a minimum of £25,000 per annum."
Roads minister Stephen Ladyman said he was aware of, and shared, the T&G's concerns.
"There are certainly some people who aren't implementing the directive properly," said Dr Ladyman.
He added that working time regulations were due to be reviewed at both government and European Union level as a result.