Which statement about pneumatic chipping tools is TRUE ________.
A.The operator must wear safety goggles or glasses
B.The equipment must be grounded to prevent shock hazard
C.The chipping mechanism is made of a non-sparking material that is safe to use near explosive atmospheres
D.The needles of the needle-type chipping gun must be replaced when they have been blunted more than 1/2 of their diameter