WHILE THE MANAGEMENT is being changed

at the Environmental Protection Agency, the evidence of recent poor judgment continues to pile up. Now it develops that the EPA has closed the small laboratory in Beltsville that tested hospital disinfectants. This retreat comes at a time of rising concern about new and tenacious hospital infections.

It is disingenuous of the EPA to say that closing the lab has nothing to do with the budget. The official explanation is that the people in that lab were needed for other work. No doubt; but they were needed for other work because the Reagan administration has cut the EPA's funds well below the minimum necessary to carry out its responsibilities.

This kind of testing could in theory be carried out by the states, or by the hospitals themselves. But it is hard to think of a more wasteful practice than to have each state, let alone each hospital, do its own tests of these standard compounds. Three states are now doing it, and you will not be reassured to know that one of them reports about a third of the tested samples to be ineffective.

There are fields in which less regulation means greater efficiency. Health care, notoriously, is not one of them. But the departed management of the EPA never seemed to get even as far as that basic point. It never gave any evidence of understanding that its job was the protection of public health. That, fortunately, is a point on which William Ruckelshaus, now returning to the administrator's office, has never needed any instruction.

There are now half a dozen congressional subcommittees examining the recent history of the EPA. One or another of them might usefully ask Mr. Ruckelshaus to take a look at his predecessors' decision to drop the disinfectants from their list of proper public concerns.