Electrostatic discharge (ESD) hazard — body charge on carpet As a person walks across a carpet, what level of static charge (approximate voltage) can the human body accumulate under dry conditions?

Introduction / Context:
Electrostatic discharge (ESD) can silently damage sensitive semiconductor devices. The human body can accumulate surprisingly high voltages, especially in low humidity and on insulating surfaces such as carpet. This question highlights why ESD controls are critical whenever handling CMOS or other sensitive ICs.

Given Data / Assumptions:

• Dry environment and carpeted flooring increase triboelectric charging.
• Human-body capacitance and friction determine accumulated voltage.
• Semiconductor gates (especially MOS) can be damaged by far lower voltages than humans can feel.

Concept / Approach:
While a person may feel a “zap” at only a few thousand volts, the body can charge to tens of kilovolts on carpet. IC damage thresholds can be below 1,000 V for many devices, so strict ESD precautions are needed: grounded wrist straps, antistatic mats, conductive packaging, and controlled humidity.

Step-by-Step Solution:

Verification / Alternative check:
ESD industry references (HBM models) often cite body voltages exceeding tens of kilovolts in uncontrolled environments, far above safe levels for MOS gates.

Why Other Options Are Wrong:

• A/B/C understate peak voltages observed in practice, particularly in very dry conditions.

Common Pitfalls:
Believing that if a user cannot feel a shock, components are safe; many failures are latent and appear later as reliability issues.

Final Answer:
Over 30,000 volts