Lightweight defenders

fitted with flexible headband, for a secure, comfortable fit, this model suits for long wearing periods. Here are ear-defenders that operatives are less likely to take off, as soon as you've turned your back.  

• Moderately good attenuation - SNR 22dB - generally suitable for use with hedge trimmers, shredders and most portable power tools.
• Conforms to EN352.
• Compatible with most, head mounted Face-shields and visors.
• Excellent value. 

Some information about Noise and its effects on the ear.

It's an old adage, amongst occupational safety experts that: moderate protection for all of the time is better than maximum protection for none of the time.

Nowhere is this more truly reflected that in the areas of noise and respiratory protection, where mostly pathogenesis is insidious and un-noticed, until symptoms develop and where (excepting where there is profound and immediate danger) illness develops from a regular barrage of insults and minor, imperceptible injuries.

Occupational Deafness and pulmonary fibrosis are just such examples.

Attenuated frequency band hearing loss is usual in all adults - men more than women and, without the encouragement of workplace (or 'clubbing') noise, by the age of twenty-five, the upper frequencies of hearing perception will have degenerated by around 4 KHz  (Vibrations of 4000 times per second). When we are children, our hearing range will usually be from about 15 to =>16,000 Hz.

The effect of high range attenuation is similar to how a person with 'normal' hearing might listen to a Hi-fi with the base turned right up and the treble turned down. It noticeably affects perception of sounds above 1Kz (which is two octaves above middle 'C', on a piano, for example.

Where work place noise is regular and exposure long, noise levels above 90 dB(A) {deci-bells in the 'key' of A - to which harmonic, the human ear is most sensitive} will cause damage when time weighted average sound pressures endure for eight hours. For this reason, EU Regulation demands that average sound pressure is less than 85 dB(A) and employers must take action to reduce the noise at source (preferably), or otherwise (as a last resort) to issue and train operatives in using suitable ear-defenders.

The relationship between Sound pressure (measured say in Pascal per unit area) and perceived loudness (Bells or decibels) is logarithmic. That is to say, for example; that when noise rises from 90 to 93 db(A), the sound pressure acting on the ear drums, will more or less double. Noise from normal conversation is usually between 55 and 70 dB(A). The noise from woodworking machinery is often between 95 and 130 dB(A) - just to paint a picture of valid comparisons. 

Ear defenders attenuate sound pressure from the environment, generally in a range from 5 to 35 dB(A) and almost always, they reduce the 'top end' frequencies more than lower frequencies - so actually, when wearing them, it's a bit like having frequency attenuated deafness! Because of this frequency bias, when wearing ear defenders, it will be easier to hear men talking than women - Quite useful, some might suggest!

We use our ears to listen for danger, to gauge when equipment is not running properly and to interpret many other signals of what is out of the ordinary.

Thus, when using ear-defenders, it is important to be conscious that these signals are less obvious and therefore, we must use our other senses to interpret danger or unusual events. You may not hear a vehicle moving towards you, for example.

It may now be clear why ear-defenders should be issued only as a ‘last resort’ in mitigating noise effects and also; why using ear-plugs might be a preferred option to ‘heavier duty’ ear defenders.

Using any or all Personal Protective Equipment presents some kind of physical challenge or restriction to our usual abilities and senses and, unless there is clear and immediate danger, which needs mitigating by using PPE, it is ILLEGAL to insist that operatives wear it!

I wish a few of our ‘Corporates’ and local authorities could come to terms with that fact – especially in the light that relative injury rates, per ‘blue-collar’ job, having actually risen, since the Health and Safety at Work Act and (later) the PPE Directive came in to force, in 1974.

It is most important to know WHEN and WHERE to be protected by using PPE; to be PROPERLY able to assess risk and to mitigate it against REAL, rather than perceived, dangers.

For this reason alone, I have taken the time to share a little of the reasoning and science behind the regulations and standards designed for your effective protection.

WP