What can happen if a standard temperature penetrant is applied to a hot test specimen?

When a standard temperature penetrant is applied to a hot test specimen, it may produce volatile fumes and a surface residue, making this option the correct choice. The reason behind this is that when penetrants are heated, their solvent components can evaporate quickly due to the elevated temperature. This can lead to the formation of fumes, which may be hazardous if inhaled. Additionally, as the solvent evaporates, it can leave behind a residue on the surface of the specimen, which can affect the effectiveness of the inspection process.

Applying a penetrant at high temperatures can compromise its ability to penetrate defects or discontinuities in the material, as the rapid evaporation might hinder proper wetting and penetration into cracks. This situation emphasizes the importance of adhering to the recommended application temperatures for penetrants to ensure accurate and safe testing results.