<human>: Is it safe to use a sandblaster to remove paint from a metal door?
<bot>: Yes, it is safe to use a sandblaster to remove paint from a metal door. Sandblasting uses compressed air and abrasive materials to blast away the paint. The abrasive material is made of silica or aluminum oxide. Silica is an inorganic compound that is non-toxic and can be handled safely without any protective equipment. Aluminum oxide is also an inorganic compound that is non-toxic and can be handled safely without any protective equipment.