To pass a visual inspection, a fillet weld must be free of porosity. Which statement best describes porosity allowance?

To pass a visual inspection, a fillet weld must be free of porosity. Which statement best describes porosity allowance?

• A. Cracks or undercut are allowed up to 2 mm
• B. No porosity
• C. Porosity up to 1 mm is acceptable
• D. Voids up to 3 mm are allowed

Answer: (B)

Porosity are tiny gas pockets trapped in the weld as it solidifies. For a fillet weld to pass a visual inspection, the surface must be free of these pores, because any porosity indicates contamination, improper shielding, or faulty welding technique and can weaken the weld. So the only acceptable condition is zero porosity—the weld must have no visible porosity at all. The other ideas imply tolerances or describe other defects. Cracks or undercut are separate surface defects and would fail a visual check. Allowing porosity or voids (even small amounts) would contradict the requirement for a clean, pore-free weld, which is why zero porosity is the correct standard for a visual pass.

Porosity are tiny gas pockets trapped in the weld as it solidifies. For a fillet weld to pass a visual inspection, the surface must be free of these pores, because any porosity indicates contamination, improper shielding, or faulty welding technique and can weaken the weld. So the only acceptable condition is zero porosity—the weld must have no visible porosity at all.

The other ideas imply tolerances or describe other defects. Cracks or undercut are separate surface defects and would fail a visual check. Allowing porosity or voids (even small amounts) would contradict the requirement for a clean, pore-free weld, which is why zero porosity is the correct standard for a visual pass.