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.
E