Images of iron lungs and children in braces served as the backdrop to a monumental search for a cure.

But as polio sufferers died and newer, more portable respiratory devices were developed, the number of people in iron lungs dwindled.

Equipment Presumptively Medical - Items such as hospital beds, wheel-chairs, haemodialysis equipment, iron lungs, respirators, intermittent positive pressure breathing machines, medical regulators, oxygen tents, crutches, canes, trapeze bars, walkers, inhalators, nebulizers, commodes, suction machines and traction equipment presumptively constitute medical equipment.