Which of the following is NOT solid waste that welders produce?

• A. Filtered air from an environmentally friendly exhaust
• B. Metal shavings
• C. Used welding rods
• D. Slag and dross

Answer: (A)

The key idea is distinguishing solid waste from emissions. Welders produce solid wastes like metal shavings from cutting or grinding, slag and dross that form during welding, and used welding rods as consumable residues. The exhaust system is meant to remove fumes and particulates from the welding plume; once the air passes through the filter, what exits is clean air, not a solid residue. So, filtered air is not solid waste produced by welding. (Note: the filter media or collected particulates inside the exhaust can become solid waste, but the air leaving the system itself is not.)