If you mean an FLIR (infra red) camera, yes,. they are very handy for checking if there are gaps in insulation or missing pieces. I've read that they can sometimes be handy for finding leaks, who knows? On the last new build I did we had a surveyor out who went round with one and identified areas where the insulation was sub-par, allowing us to take remedial action before the air test (perhaps this is what you meant by a "draft test"?). It is possible to buy FLIR add-on modules for many smart phones at £200 and upwards (TBH something I am seriously considering) - they have a narrow field of view and relatively low resolution agsinst a proper FLIR camera, but still seem good enough to find defects in insulation. Sadly, a lot of newer buildings have poorly installed insulation - this is partly because on many builds insulation gets installed in a haphazard and poorly controlled manner with little care taken to ensure the required tight fits and little ot no supervision.
In an air test the doors and windows are all closed and a large fan mounted in a baffle plate is installed in the front door opening and the edges sealed. The fan is switched on and generates negative pressure in the building. You then go round finding air leaks using a non-toxic smoke spray (
@JohnD's suggestion of joss sticks works just as well) - and wherever possible sealing the leaks with expanding foam and/or silicone. You can get a domestic air test done, but it won't really help you locate defects in insulation.
