Which term indicates an airtight seal created by fusion or soldering?

• A. Hammertone finish
• B. Hardboard
• C. Hermetically sealed
• D. Head panel

Answer: (C)

Airtight sealing achieved through joining materials with fusion or soldering is described as hermetically sealed. This term specifically communicates that the seal prevents air and moisture from passing in or out, creating a truly airtight boundary. In practice, achieving this kind of seal relies on techniques that fuse surfaces or apply solder to form a continuous, gas-tight barrier, which is essential for protecting contents from exposure to the surrounding environment.

The other terms don’t convey an airtight seal. Hammertone finish refers to a textured paint appearance, hardboard is a dense wood-fiber panel, and a head panel is a component of a casket. None of these imply an airtight seal created by fusion or soldering.