How Are Helmet-Mounted Ear Defenders Tested for Safety and Performance?

When it comes to hearing protection, it’s essential that mounted ear defenders are tested to be fully compatible with the helmets they’re paired with. This process goes beyond just checking the fit — both physical and acoustic tests are needed to ensure they’ll actually perform at the right level. Even after testing, these ear defenders and helmets need to be certified as a combination, which allows a certified authority to keep an eye on their ongoing compliance.

Physical Testing

Adjustability
Mounted ear defenders have to fit within a specific size range, so they’re attached to a helmet and tried on test headforms of various sizes to make sure they’ll work for real people.

Cup Rotation
The cups need to rotate enough to create a solid seal around the ear, which is key for blocking out sound effectively. For this test, the ear defenders and helmet are put on a special fixture that rotates the cups, ensuring the cushions stay in contact and maintain the seal.

Headband Force
Ear defenders have to provide a tight seal without being too tight, so this test looks at the force created by the headband when paired with a helmet. A good seal is essential for protection, but the force should stay below 14N for comfort.

Cushion Pressure
This test checks the pressure the cushions exert against the wearer’s head by dividing the headband force by the cushion area, and it shouldn’t exceed 4500 Pa.

Drop Resistance
To make sure everything holds up on the job, the helmet and ear defenders are attached to a test rig and dropped from a height of 1 metre, slamming into a steel plate. They need to remain intact and functional afterward.

Headband Force Change
Since gear gets used repeatedly, the headband is flexed 1000 times to see if the force it applies changes over time. After all those cycles, it’s measured again to confirm it doesn’t exceed 14N and stays within 15% of the original reading.

Leakage Resistance
Fluid-filled cushions are placed under a 28N load to check for any leaks or ruptures, ensuring they can handle pressure without failing.

Ignitability
Safety equipment should be as fire-resistant as possible. All ear defender parts, including the supporting arms, are tested with a steel rod heated to 650°C to make sure they won’t catch fire or keep glowing.

Acoustic Testing

Insertion Loss
This test uses a microphone to measure how well the ear defenders block out noise across different frequencies, ensuring they offer adequate noise reduction without big variations in performance.

Sound Attenuation
People test out the ear defenders by listening to controlled sounds in a noise chamber. First, they listen without protection, then with the ear defenders on, to gauge the difference in what they hear.

Testing for Different Helmet Combinations

After ear defenders are certified with one helmet, they can be tested with additional helmet models to confirm compatibility. These tests focus on adjustability and headband force, and further sound testing is only needed if the headband force isn’t within set limits.

Why Certification Matters

Certification ensures that ear defenders and helmets are continuously compliant with safety standards. As a category III PPE item, hearing protection must pass regular audits and retests by a certified body. Certification isn’t just a one-time event; it ensures that if the product design or manufacturing changes, any necessary testing is done to confirm performance.

Having properly certified, well-tested gear can mean the difference between effective protection and a potential safety risk. To ensure your safety and comfort, shop for quality PPE and safety workwear at PPE Store!