For underwater ultrasound, the recommended immersion medium is which?

For underwater ultrasound, the recommended immersion medium is which?

• A. Distilled water
• B. Salt water
• C. Tap water
• D. Sea water

Answer: (A)

When underwater ultrasound is used, the immersion medium should provide predictable, minimal attenuation and be inert to the equipment. Distilled water is pure and free of dissolved minerals and salts, so it offers very stable acoustic properties and reduces the risk of electrical conductivity, corrosion, or residue forming on the transducer. Salt-containing waters (sea water or salt water) change the sound speed and attenuation and can cause corrosion or buildup, while tap water contains minerals and impurities that introduce variability. Distilled water therefore gives the most consistent coupling for accurate ultrasound transmission and measurement.

When underwater ultrasound is used, the immersion medium should provide predictable, minimal attenuation and be inert to the equipment. Distilled water is pure and free of dissolved minerals and salts, so it offers very stable acoustic properties and reduces the risk of electrical conductivity, corrosion, or residue forming on the transducer. Salt-containing waters (sea water or salt water) change the sound speed and attenuation and can cause corrosion or buildup, while tap water contains minerals and impurities that introduce variability. Distilled water therefore gives the most consistent coupling for accurate ultrasound transmission and measurement.