The second biggest teaching union advised its 223,000 members yesterday to stop taking children on school trips because "society no longer appears to accept the concept of a genuine accident".
The NASUWT, which said the ban applied to "any excursion outside the perimeter of the school", has seen three of its members blamed for causing pupils' deaths.
One, Paul Ellis, is serving a 12-month sentence after pleading guilty to the manslaughter of a 10-year-old boy who drowned on a school trip to the Lake District. Two others were criticised after two teenage girls on a trip they were supervising in the Yorkshire Dales drowned in a beck.
"It is highly regrettable that we have been forced to advise members against taking school trips but our first responsibility must be to protect their interests," said Eamonn O'Kane, the general secretary.
"When something goes wrong, the leader bears a legal responsibility so the finger of blame will almost certainly point at the teachers."
An accident was no longer treated as an accident, he said. Instead, it led to lengthy inquiries by the police, the local education authority and the Health and Safety Executive, the suspension of the teachers involved and extensive publicity.
Because of growing allegations of abuse, the union has also advised members not to give children a lift in their own vehicles, not to place themselves in a "one-to-one situation" with a child and not to drive a minibus on an educational visit.
Should be interesting to see what the Government reaction to this one is...