Determine the SSD mass of the specimen after drying it thoroughly with a dry towel.

• A. Wet mass
• B. SSD mass after drying
• C. Dry mass after air drying
• D. Saturated mass

Answer: (B)

Saturated Surface Dry (SSD) mass is the mass of a specimen after surface water has been removed while the pore spaces remain filled with water. Drying with a dry towel accomplishes this: you wipe away any free moisture on the surface, but the moisture stored in the pores stays inside. That’s exactly the SSD condition, so the measured mass is the SSD mass after drying.

The other options don’t fit because wet mass includes surface water, dry mass would mean all moisture is removed (oven-dry or air-dried to the point of no moisture), and saturated mass would imply the pores are fully filled with water with no surface moisture removed.