Members of the Westminster and Scottish Parliaments also sought details on how the inspectors apparently managed to carry explosives, guns and knives through the airport's security checks undetected.
The inspectors, from the Department of the Environment, Transport and the Regions made the spot check at Edinburgh airport last week.
Airport staff failed to notice a gun strapped to one inspector's back, while another inspector who had Semtex in his briefcase passed successfully through baggage control. A third had a butterfly knife strapped to her leg, according to reports. Only one of the inspectors who tried to smuggle weapons on to domestic and international flights was detected and halted.
The spot checks demonstrate how hard it is to catch weapons and explosives even with sophisticated equipment. Security experts point out that watching video screens is boring, yet it requires close concentration to notice the one-in-a-million case of dangerous material passing through.
"It is obviously bad news that three out of the four got through undetected," said Dr Jim Swire, a spokesman for Lockerbie Families - Flight 103 whose daughter died in the 1988 bombing. "Things are not right at Edinburgh airport and will have to be improved. The good news is that this shows that the Department of Transport is checking security. This will keep people on their toes."
Gwyneth Dunwoody, chairman of the Select Committee on Transport, said the results of the spot check must be acted on quickly. "It is important that Parliament is informed of what has happened. I am assuming that information will, in due course, be made available."
Donald Gorrie, the Liberal Democrat MP and MSP for Edinburgh West, which covers the airport, said: "If the reports are right then it is a bad failure by security. This is a very serious lapse and the whole system will need to be tightened up."
A spokesman for the Transport Department said: "We can confirm that the checks took place last week. We don't discuss our security methods for the obvious reason that we don't want to give them away."
A spokeswoman for BAA, the airport's owner and operator, said the company did its own checks in addition to those made by the department.