Fingertight

Today I discovered that while 'fingertight' HPLC fittings are truly easy to install, it's almost impossible to determine whether there is pressure behind one. With a Valco fitting, if you  loosen a joint, it will bleed a small amount of high-pressure fluid. If you try that with the  'fingertight' fittings the tube just jumps out and sprays fluid all over the place. It's a good thing  I was using carbon dioxide when this happened the first time!