Question

Which of the following is NOT suitable for making a cast of footprints in snow ?

• A. Plaster of Paris
• B. Snow Print wax
• C. Sulphur
• D. Paraffin

Hint:

Never use Plaster of Paris directly on snow → Heat melts impression. Use snow wax first.

Answer 1

The Correct Option is A

Concept: Casting of footprints is an essential technique in forensic investigation. However, different surfaces require different casting materials. Snow is a delicate and temperature-sensitive surface, so the choice of casting material must prevent melting or distortion.

Step 1: Understanding the nature of snow impressions.
Snow is fragile and easily melts when exposed to heat or pressure. Therefore, any casting material used must not generate heat or exert excessive pressure.

Step 2: Evaluating Plaster of Paris.
Plaster of Paris (POP) undergoes an exothermic reaction (releases heat) while setting. This heat can melt the snow, thereby destroying the footprint impression.
Thus, it is NOT suitable.

Step 3: Evaluating Snow Print Wax.
Snow print wax is specifically designed to stabilize snow impressions before casting. It prevents melting and preserves details.
Thus, it is suitable.

Step 4: Evaluating Sulphur and Paraffin.
Sulphur and paraffin can be used in specialized casting methods as they can solidify quickly and capture details without significantly damaging the impression when used properly.

Step 5: Final evaluation.
Among all options, Plaster of Paris is the only material that can damage snow impressions due to heat generation. Final Conclusion:
Hence, the correct answer is (1) Plaster of Paris.