â¢ Position the grinder in a way that the guard provides the maximum protection to the operator from sparks and/or flying debris. â¢ Use caution when grinding in corners because a sudden, sharp movement of the grinder may occur when the wheel strikes the secondary surface.
A boater may not approach within 100 yards of a military vessel; it must slow to minimum speed within 500 yards of any naval vessel. 8 people found this useful.
In general the aircraft must be at least 500 feet away from any person, vessel, vehicle, or structure. In congested areas the aircraft must stay 1000 feet above the highest obstacle within a 2000 foot radius of the aircraft. There are special rules for helicopters that allow them to fly closer than these general limits.