Hazards exist in every workplace in many different forms: sharp edges, falling objects, flying sparks, chemicals, noise and a myriad of other potentially dangerous situations. Employers must provide personal protective equipment (PPE) to their employees and ensure its use, while employees have a responsibility to properly wear and maintain their PPE. When it comes to hearing this can often be taken for granted, by both the employer and employee, especially at intermediate volumes. Unlike something like a fall, the result of which is immediate and well understood, the long term damage done by hearing loss is less of a concern and may cast aside in favor of short term comfort.

When it comes to hearing this can often be taken for granted, by both the employer and employee, especially at intermediate volumes. Unlike something like a fall, the result of which is immediate and well understood, the long term damage done by hearing loss is less of a concern and may cast aside in favor of short term comfort.

If you’re in that situation and want to commit to long term hearing health, then a Hearing Conservation Program is where you should start. However, if you already have a program in place or are just looking to learn more about the different types of hearing protection, this guide will walk you through what you need to know.

GENERAL INFO

Decibels – Decibels is the unit of measurement for sound. The higher the rating, the louder the noise is. The ratings increase logarithmically, which means that a noise at 70 dB’s is ten times louder than something that is 60dB. Below is OSHAs chart of permissible noise exposure in a work day:

NRR Rating – The performance of earplugs and earmuffs varies between brands and styles. One way to choose a hearing protector is to compare Noise Reduction Ratings. The Noise Reduction Rating, or NRR, measures the muff’s or plug’s ability to block out noise or “attenuate”; sound. This measurement is stated in decibels; a plug with an NRR of 26 blocks out a maximum of 26 decibels of noise. The NRR listed is the maximum protection that could be achieved if the plug fit the wearer perfectly and was inserted correctly. In most work situations attenuation is half of the listed NRR. For example, if the NRR is 30 the hearing protector most likely blocks out 15 decibels of noise.

TYPES OF PROTECTION

Pre-Molded Earplugs

Pre-molded plugs are made from silicone, plastic or rubber and are manufactured as either “one-size-fits-most” or are available in several sizes. Many pre-molded plugs are available in sizes for small, medium or large ear canals.

The plugs should seal the ear canal without being uncomfortable. This may take some trial and error, so test various designs and sizes to find the best fit. Also note: a person may need a different size plug for each ear, so keep that in mind when making selections.

Directions for fitting each model of pre-molded plug may differ slightly depending on how many flanges they have and how the tip is shaped, so be sure to check the box or manufacturers instructions. Insert this type of plug by reaching over your head with one hand to pull up on your ear. Then use your other hand to insert the plug with a gentle rocking motion until you have sealed the ear canal.

Advantages of pre-formed earplugs

• Effective protection with proper insertion depth
• Durable – can be washed and re-used several times until dry and cracked.
• Easily carried on uniform or clothing in earplug carrying case
• Less expensive than ear muffs and hand-formed earplugs for frequent users (in the long run)
• Fairly comfortable although adaptation period may be needed.

Disadvantages of pre-formed earplugs

• Frequent insertion may cause irritation (minimized by proper fitting)
• Works loose with jaw movement (talking, chewing) which can require user to re-insert earplug often
• Improper fit reduces effectiveness or attenuation benefit
• Employees may wear them for too long or not clean them properly
• May require a different plug for each ear

Foam Earplugs

These plugs are made of a formable material designed to expand and conform to the shape of each person’s ear canal. When worn properly these typically provide better protection than pre-formed.

Roll the expandable plugs into a thin, crease-free cylinder. You should have a smooth tube thin enough so that about half the length will fit easily into your ear canal. After insertion the plug will expand and seal the ear canal. Some individuals, especially women with small ear canals, have difficulty rolling typical plugs small enough to make them fit.

Advantages of hand-formed earplugs:

• Effective protection when properly inserted into ear canal
• Most comfortable – generally half of employees prefer them
• Universal fit – regular size fits 90% of population; small or large sizes available for other 10%
• Individual medical fitting not required
• One time use – hygienic IF hands are clean when inserting
• Least expensive of all HPD’s for full time or very infrequent use; however, cost goes up if multiple earplugs are used per day
• Good choice when hat or helmet required – nothing sticks out of canal to “catch” the helmet.

Disadvantages of hand-formed earplugs

• Must be properly molded into small smooth cylinder shape with no creases and inserted deeply into ear canal
• Easily soiled and absorbs dirt and oil that can be transferred into the ear canal
• Must be properly inserted – color of earplug should not be visible when viewed directly in front
• One-time use – so continual supply is needed; remind employees not to re-use

 

Canal Caps

Canal caps resemble earplugs on a flexible plastic or metal band. The earplug tips of a canal cap may be a formable or pre-molded material. Some have headbands that can be worn over the head, behind the neck or under the chin. Newer models have jointed bands increasing the ability to properly seal the earplug.

The main advantage canal caps offer is convenience. When it’s quiet, employees can leave the band hanging around their necks, and when noise begins again they can quickly insert the plug. However, they are typically not the best full time solution.

Advantages of ear canal caps

• Quickly inserted without soiling
• Universal fit – individual medical fit not required
• Lightweight and easily carried around neck for immediate use
• Best for intermittent and modest noise (95dB or less)

Disadvantages of canal caps

• More expensive than earplugs
• Uncomfortable after extended use
• Limited attenuation
• Poor headband tension greatly reduces effective attenuation/protection

Earmuffs

Earmuffs come in many models designed to fit most people. They work to block out noise by completely covering the outer ear. Muffs can be “low profile” with small ear cups or large to hold extra materials for use in extreme noise. Some muffs also include electronic components to help users communicate or to block impulsive noises.

Workers who have heavy beards or sideburns or who wear glasses may find it difficult to get good protection from earmuffs. The hair and the temples of the glasses break the seal that the earmuff cushions make around the ear. For these workers, earplugs are best. Other potential drawbacks of earmuffs are that some people feel they can be hot and heavy in some environments.

Advantages of ear muffs

• Effective protection or attenuation of noise
• Universal fit — as long as headband adjusts
• Individual medical fit not required
• Can be worn with earplugs for double protection in extreme noise situations
• Can incorporate communication equipment and/or Active Noise Reduction (ANR) features

Disadvantages of noise muffs

• Most expensive type of HPDs
• Bulky and heavy
• Uncomfortable in heat and humidity due to perspiration
• Hair/eyeglasses/earrings decrease fit effectiveness
• Not easily carried

**Earmuffs are also used when “double protection” is required, that is the use of both an ear plug and earmuffs together. While this does reduce the noise exposure even more, it should be noted that the NRR ratings are not added together. When using double hearing protection add 5 to the higher of the two NRR ratings. So if an employee wore NRR 26 ear plugs and NRR 30 ear muffs, their effective noise reduction would be 20 (30/2 + 5).

About Martin

Martin Supply is ready with the right solution and product expertise to help your company with safety compliance and OSHA laws/standard changes. Our goal is to strategically partner with our customers to develop the best custom tailored safety solutions for your workforce. To learn more about Martin’s Custom Tailored Safety Solutions, contact us today and we’ll come out to your facility and help you make sure that your facility is protected from hazardous noise.