The news comes amidst moves by major retailers to introduce tougher criteria for engineers as they meet their responsibilities under the F-Gas regulations.
The end user group of the British Refrigeration Association want to tighten up on the standards of workmanship on new installations.
Measures being called for include insisting on naming individual engineers on new installations, routine cutting into completed joints to test brazing quality and a registration scheme for competent workers.
Bob Arthur of Marks and Spencer, who chairs the BRA end user group, is leading the drive. He said he is asking consultants to cut into several joints for every new installation, so the quality of brazing could be confirmed.
He said: “I have been shocked at the quality of some of the work I have had inspected already and it is just not good enough if we are to stop leaks. We have found substandard work and substandard materials.”
Mr Arthur has now written to all his contractors, warning them that engineers who are found to be below standard will be banned from site.