Sound solutions. Applied to hearing loss prevention.

We understand the needs of Canadian workers loud and clear. What level of hearing protection are your employees actually receiving? Every employee is different. Every job is different. Every ear is different. Noise induced hearing loss is 100% preventable. Discover how 3M science helps you get smarter about hearing protection.

Worker Training

Noise Induced Hearing Loss


The Path to Prevention

Developing and managing an effective hearing conservation program can be overwhelming and challenging, especially if you don't know where to start. At 3M we have extensive experience working with our Canadian customers helping them solve their most complex hearing conservation challenges. It's through these experiences that we make available to you a comprehensive collection of training tools, regulatory updates and general insights to support our common goal of preventing Noise Induced Hearing Loss in the workplace.


Frequently Asked Questions


  • When do I need hearing protection?

    You need to consult the regulations in the jurisdiction you work within.
    • According to CSA Z94.2-14,when the 8-hour average noise exposure limit is greater than 85 dBA.
    • As a rule of thumb when you feel the need to shout in order to be heard 1 meter/three feet away, the noise levels are probably 85 dBA or more and hearing protection may be required.
  • What noise level requires hearing protection?

    According to CSA Z94.2-14, all individuals exposed to noise greater than 85dBA shall be provided with appropriate hearing protection.
    • Consult the local authority in your jurisdiction to confirm noise level requirements in your workplace.
  • Is there a proper technique for inserting foam earplugs?

    1. 1. Slowly roll and compress foam earplugs into a very thin crease-free cylinder.
    2. 2. Insert compressed earplug well into ear canal while pulling ear outward and upward with opposite hand.
  • How do I insert reusable earplugs properly?

    Reach around the head and pull outward and upward on the ear. Insert the rounded tip, gently twist until ear feels sealed, leaving stem outside for removal. Carefully twist or rock the earplug to break the seal for a slow, safe removal.
  • How do I know if my 3M™ Earplugs fit correctly?

    After proper insertion while listening to a steady noise, press cupped hands firmly over your ears. With properly fitted plugs, the noise levels should be about the same whether or not the ears are covered.
  • What are the best hearing protectors?

    The ones that fit your ears well and are comfortable.
    • Hearing protectors must fit properly to block noise.
    • Hearing protectors that fit comfortably are more likely to be:
      • worn correctly, and
      • worn for the entire time you are exposed to potentially hazardous noise
  • How is hearing protection rated?

    Each hearing protection device is labelled with both the Noise Reduction Rating (NRR) and CSA class. It is required by CSA that the NRR is derated to better reflect the level of protection a worker will receive. Please consult the standard for the NRR derating scheme and CSA class assignment.
  • What is the Noise Reduction Rating (NRR)?

    It is a description of how much attenuation (noise reduction) the hearing protectors provided in a laboratory test
    • The NRR describes the ‘best fit’ of hearing protectors when they are worn under ideal conditions.
    • Like the mileage rating label on a new car, the NRR does not take into account the conditions under which the buyer may use the product.
  • Is the NRR a good estimate of how much protection will be obtained by people who wear these devices?

    No. At work or at home, the noise reduction obtained by wearers varies widely.
    • Among a group of people wearing the same hearing protectors, some individuals obtain high noise reduction while others obtain much less due to differences in:
      • hearing protector fit
      • the fitting skill of the wearer, and
      • motivation of the wearer
    • CSA recommends individual fit testing using a Field Attenuation Estimation System such as the 3M™ E-A-Rfit Validation System to measure the noise reduction each person obtains from their hearing protectors.
  • Are hearing protectors with a Noise Reduction Rating (NRR) of 32 decibels (dB) more effective than those with an NRR of 30 dB?

    No, differences in NRR of 3 dB or less are not significant when comparing hearing protectors
    • Because of the variability of the laboratory procedure used to measure the attenuation of hearing protectors, differences between NRR values of 3 dB or less are not statistically significant.
  • How much noise reduction is enough?

    For most people, 10-15 dB of effective noise reduction is enough to lower their Time-Weighted Average (TWA) noise exposure to 85 dBA– the level recommended by CSA.
    • More noise reduction may be needed for:
      • TWA noise exposures higher than 95 dBA, and
      • Longer exposure times (more than 8-hours) at TWA levels higher than 90 dBA, and
      • People who have already experienced a hearing loss due to loud noise exposure
    • CSA requires employers to provide hearing protectors that are capable of lowering TWA employee noise exposures to below 85 dBA. Consult the local authority in your jurisdiction for your noise exposure limits.
      • Employees who have experienced a hearing loss known as a Significant or Standard Threshold Shift (STS) must be provided with hearing protectors capable of reducing their TWA exposure to 85 dBA.
  • Do high NRR earplugs always provide more protection than earmuffs?

    No. Workplace studies indicate that earmuffs often provide more noise reduction than earplugs despite differences in the Noise Reduction Rating (NRR).
    • Obtaining a good fit with earmuffs is relatively easy, even with minimal training, and
    • Compared to earplugs, earmuffs may fit more consistently each time they are worn.
  • How much extra noise reduction can be obtained when earmuffs are worn together with earplugs?

    According to CSA Z94.2-14, ‘Dual-Protection’ provides 5 dB of additional noise reduction over what is provided when the device with the highest NRR is worn by itself.
    • The combined noise reduction is influenced primarily by the fit of the earplugs
    • The amount of extra noise reduction obtained is:
      • Greater for low frequencies than for high frequencies, and
      • About the same regardless of which earmuffs are worn.
  • Is there a way to measure the effectiveness of my earplugs or earmuffs?

    Yes, fit-testing is available by 3M for both earplugs and earmuffs using the 3M™ E-A-Rfit Dual-Ear Validation System.
    • A fit-testing system provides a Personal Attenuation Rating (PAR) which indicates the level of protection the worker is receiving from his / her protection device.
    • A new standard, CSA Z1007-16, includes fit-testing as one of the four selection methods used when determining the most appropriate hearing protector.
  • What effect do safety glasses have on the noise reduction provided by earmuffs?

    The noise reduction may be lower when eyeglasses, goggles or respirator straps are worn between the sealing surface of the earmuff cushions and the sides of the wearer's head.
    • The amount of noise reduction lost may be as high as 3 to 8 dB; more for low frequencies, less for high frequencies.
    • For best noise reduction, select eyeglasses or goggles that have thin, flat temples or straps which will minimize interference with the seal of the earmuff cushions.
    • Pull long hair back to the extent possible and remove other items that may degrade the earmuff seal such as pencils, hats, jewelry or earbuds.
    • 3M recommends fit-testing your earmuffs while wearing your safety glasses to identify if the temples are impacting the level of protection you need.
  • Are hearing protectors effective for shooting?

    Yes. Hearing protectors are capable of significantly reducing the risk of damage to your ears caused by gunfire.
    • For maximum noise reduction, wear disposable foam earplugs fit deeply in the ear canal in combination with comfortable, lightweight earmuffs
    • For improved communication and/or situational awareness, wear level-dependent earplugs or earmuffs.
      • These hearing protectors, though not as protective as foam earplugs or conventional earmuffs, provide noise reduction that increases with sound level. This allows protection against very loud gun shots but the wearer can hear conversation or ambient sounds in between shots.
      • Types of level-dependent hearing protectors include:
        • 3M™ Peltor™ Tactical Earmuffs
    • More noise reduction may be needed when you are shooting:
      • A large number of shots, and
      • High-powered firearms
  • Can disposable foam earplugs be washed and reused?

    Washing foam earplugs is generally not recommended but they can be reused several times before they are thrown away.
    • Replace foam earplugs when they are:
      • Damaged, dirty or coated with earwax, or
      • No longer soft and pliable or do not return to their original uncompressed shape when removed from the ear.
  • Am I more likely to have ear infections if I wear earplugs?

    No. The incidence of ear infections among people who regularly wear earplugs is no higher than among the general population.
    • To prevent irritation of the skin in the ear canal, always wear clean earplugs
    • Never attempt to clean your ear canal with a cotton swab.
  • What is the purpose of metal detectable ear plugs?

    3M™ Metal Detectable Earplugs contain a medical grade stainless steel ball bearing and the cord contains a metal oxide for detection at manufacturing facilities.
    • Metal Detectable Corded Earplugs are ideal for use in the food production and processing industries where contamination prevention is critical
  • What is the CSA “exchange rate” for noise exposure?

    The CSA exchange rate describes the increase or decrease in sound level (dB) that is required to cause the daily noise dose of a worker to double or be reduced by half.
    • CSA uses a 3 dB exchange rate. When the worker’s 8-hour TWA noise exposure increases by 3 dB, his daily noise dose doubles. When the TWA noise exposure decreases by 3 dB, the daily noise dose is reduced by half.
    • Whenever the noise dose increases, the amount of time (in hours) that the worker may be exposed to that sound decreases. Conversely, when the noise dose decreases, more time each day at that level is allowed.
    • Consult the local authority in your jurisdiction for your exchange rate. Example: it is 5 dB in province of Quebec
  • Is hearing loss preventable?

    Noise Induced Hearing Loss (NIHL) is 100% preventable.
    • The first step to prevention is to eliminate the noise at the source and if this is not feasible, then hearing protection devices must be used.
    • According to CSA, if a person has an average 8 hour exposure of over 85 dBA than hearing protection should be used.