hard cups which fit over the ear and are sealed to the head with soft cushion seals. Two types of seal are in general use: a "liquid seal" type comprises a soft annular tube filled with liquid, more robust cushions are filled with soft plastic foam.
HEARING PROTECTION.
- Earplugs and similar devices.
- Full acoustic helmets.
- Earmuffs which can be fitted to industrial helmets.
- Ear defenders with receiver for LF induction loop.
- Ear protection with intercom equipment.
