Dead Zones
Quick definition
Dead zones are areas of a mask where LEDs stop lighting properly, so part of your face gets less treatment than the rest.
The Science
Dead zones usually appear when internal wiring, connectors, or LED clusters fail. They are more common in flexible masks that are folded too aggressively or stored badly over time. A mask can still switch on overall while quietly losing coverage in one cheek, around the mouth, or near the nose.
Why it matters for your skin
Uneven coverage means uneven dosing. If part of the mask stops working, results become less predictable and the device may no longer be worth using for a full-face routine.