Air operated diaphragm pumps have become standard throughout almost every manufacturing and process industry in the U.K. The advantages they have over conventional pumps is that they can run dry, they self prime, they can handle solids, and they are abrasion resistant. They can cope with a wide range of nasty, high viscosity chemicals and if they are dead headed against a closed discharge valve, they simply stall. They are built to be almost idiot proof.
They can also be used in potentially explosive atmospheres and are therefore ideal for use on hazardous applications such as where petrol has been spilled, in paint factories, distilleries and any other area where there is the potential for dangerous, flammable fumes to ignite. They of course, have to be properly earthed, to avoid the possibility of a spark due to static electricity, but generally air operated double diaphragm pumps are a Number 1 solution.