Which current level is typically associated with no sensation?

Which current level is typically associated with no sensation?

• A. 0.5 milliamp
• B. 5 milliamp
• C. 25 milliamp
• D. 200 milliamp

Answer: (A)

Perception threshold for electrical current through the body is the key idea. At very low currents you typically don’t feel anything. The level around 0.5 milliamp is generally below the sensation threshold for standard alternating current through the body, so it’s the one most likely to produce no sensation. As current increases to about a few milliamp, a tingling becomes noticeable. Around 25 milliamp, the shock can be strong and cause muscle contraction, sometimes making it hard to let go. At much higher currents, like a couple hundred milliamp, the danger rises sharply with risks such as dangerous heart rhythms. So the current most commonly associated with no sensation is 0.5 milliamp.

Perception threshold for electrical current through the body is the key idea. At very low currents you typically don’t feel anything. The level around 0.5 milliamp is generally below the sensation threshold for standard alternating current through the body, so it’s the one most likely to produce no sensation. As current increases to about a few milliamp, a tingling becomes noticeable. Around 25 milliamp, the shock can be strong and cause muscle contraction, sometimes making it hard to let go. At much higher currents, like a couple hundred milliamp, the danger rises sharply with risks such as dangerous heart rhythms. So the current most commonly associated with no sensation is 0.5 milliamp.