Impact surface

Impact surface

• A. A painting on a wall
• B. A stair that is worn
• C. A door frame that experiences repeated impacts
• D. A heavy-use doorknob hitting a wall

Answer: (C)

An impact surface is a surface that is repeatedly struck or rubbed during normal use, which can cause paint to crack, chip, or flake and create lead-containing dust or chips. A door frame fits this idea best because doors repeatedly strike the frame every time they open and close, causing the paint on the frame to degrade over time. The other examples don’t show repeated blunt impacts as part of typical use: a painting on a wall is a decorative item rather than a surface that endures ongoing impacts; a worn stair shows wear from friction and foot traffic rather than repeated blows; a heavy-use doorknob hitting a wall describes a surface (the wall) being struck, but the example highlights the object causing the impact rather than the surface that endures repeated impacts.

An impact surface is a surface that is repeatedly struck or rubbed during normal use, which can cause paint to crack, chip, or flake and create lead-containing dust or chips. A door frame fits this idea best because doors repeatedly strike the frame every time they open and close, causing the paint on the frame to degrade over time.

The other examples don’t show repeated blunt impacts as part of typical use: a painting on a wall is a decorative item rather than a surface that endures ongoing impacts; a worn stair shows wear from friction and foot traffic rather than repeated blows; a heavy-use doorknob hitting a wall describes a surface (the wall) being struck, but the example highlights the object causing the impact rather than the surface that endures repeated impacts.