If high-tech devices are not available, drawing _____ lines over cracks and watching the lines move out of alignment or using an observer can assist with monitoring potential collapse.

• A. Chalk
• B. Marker
• C. Tape
• D. Paint

Answer: (A)

When high-tech devices aren’t available, you rely on simple, visually observable cues to detect movement. Drawing chalk lines over cracks creates a sharp, high-contrast mark that is easy to see on dusty or rough surfaces common in collapse environments. Chalk is temporary and easily re-marked, so you can compare a new line to the original to detect any widening or misalignment without leaving permanent changes to the structure. It won’t seal or alter the crack, and it’s quick and inexpensive to apply.

Markers can smear or fade with dust and moisture, tape can peel or distort, and paint is permanent and harder to rework, potentially obscuring cracks or complicating later assessment.