INTERACTIVE LESSON & SIMULATOR
Interactive Physics: Phone Radiation & Distance Rules
Visualize near-field cellular transmitter bursts, inverse-square law falloff at 1 ft vs 6 ft, and airplane mode isolation.
It's near-field magnetic induction, not radio
Qi wireless charging works by near-field magnetic induction between two coils, operating at roughly 85–205 kHz — far below radio frequencies, and closer in physical mechanism to an induction cooktop than to a phone's cellular or Wi-Fi antenna. The Qi standard is built for charging distances of a few centimeters at most, delivering roughly 5–15 watts to a phone-sized device.
How it's tested and regulated
Wireless charging equipment sold in the US is evaluated against FCC RF exposure rules, with specific test guidance published for wireless-charging applications; in Europe, testing follows the IEC/EN 62311 framework, which covers electronic equipment against human-exposure restrictions from 0 Hz up to 300 GHz. These frameworks require manufacturers to demonstrate compliance with reference exposure limits before a charger can be sold.
What's actually known and not known
Published testing methodology for wireless chargers is well documented, but we did not find publicly reported measurement results or compliance data for specific consumer charging pads on the market — the available sources describe how testing is done, not field-strength numbers from tested products. That's a real gap in publicly available information, not a claim that current chargers are unsafe.
A reasonable way to think about it
Because it's near-field and low-frequency, the field drops off quickly with distance from the coil — which is also why the phone has to sit almost directly on the pad to charge at all. A charging pad a few centimeters away from you while charging is a fundamentally different exposure profile than an RF source like a phone actively transmitting to a cell tower.