Unions at Cornwall's largest hospital are angry that ambulances have once again been forced to queue.
At one point on Tuesday eight paramedic teams were tied up while waiting to hand over their patients at the Royal Cornwall Hospital's A&E department.
It comes despite assurances from hospital managers last month that the problem would be addressed.
The hospital said Tuesday was an exceptional day with 195 patients seen at Accident and Emergency.
At one point 40 people were bought in in four hours.
Unison says this is now becoming a regular occurrence and it could have a drastic effect on response times.
Spokeswoman Sue Wolstenholme said: "There's going to be some waiting time and there was.
"Part of the work we have been doing with the Westcountry Ambulance Service is to work with crews and they have been phenomenally helpful in the A&E department.
"We are all working together to get patients seen and treated more quickly."
Ian Knight, chairman of the Westcountry Ambulance Unison branch, blamed the lack of hospital beds.
He said: "We thought the problem had been solved, but it has started to reappear, so we are getting incidents like this every fortnight."
The union is hoping to meet hospital managers next week for talks on the issue.