Modern head and face personal protective equipment (protective helmets, face shields) allow the headband diameter to be precisely adjusted with minimal effort using a ratchet mechanism or a headband strap lock.
Smooth adjustment is performed using a ratchet: turning it adjusts the headband diameter to the required size without removing the PPE from the head.
The PPE headband can also be adjusted using the headband strap lock as follows:
- Open the lock. Pinch the lock between the thumb and forefinger so that the retaining strap moves freely within the lock.
- Open the headband. Slide the retaining strap to the last notch so that a free end of the strap remains.
- Adjust to head size. Put on the PPE and, while wearing it, tighten the retaining strap to fit the head.
- The headband must be adjusted each time the helmet is worn.
