What precautions should I take regarding fumes and gases when welding?

Keep your head out of the fumes and do not breathe them. If inside, ventilate the area and/or use local forced ventilation at the arc to remove welding fumes and gases. If ventilation is poor, wear an approved air-supplied respirator. Do not weld in locations near degreasing, cleaning, or spraying operations, and do not weld on coated metals like galvanized, lead, or cadmium plated steel without proper ventilation and respiratory protection.