How much current can cause the heart to go into fibrillation?

Fibrillation of the heart can occur when the heart experiences a significant amount of electrical current passing through it. This can disrupt the normal rhythmic contractions of the heart muscles and lead to a potentially fatal condition. Various studies and safety standards indicate that currents as low as 100 milliamps (ma) can be sufficient to induce ventricular fibrillation in a human heart under certain conditions.

At this level of current, the heart cannot stabilize its rhythm, leading to chaotic electrical activity. While lower currents may also pose risks, particularly in sensitive individuals or under certain circumstances, 100 ma is commonly recognized in many electrical safety guidelines and standards as a threshold that can result in fibrillation.

Understanding this threshold is crucial for those working in electrical fields, as it underscores the importance of safety measures and awareness regarding electrical shock risks.