The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("the WCB") that their claim was not acceptable. A hearing was held on June 18, 2024 to consider the worker's appeal.

Issue

Whether or not the claim is acceptable.

Decision

The claim is not acceptable.

Background

The worker submitted a Worker Hearing Loss Report to the WCB on September 23, 2020, reporting a gradual hearing loss they became aware of in 2020 which they related to their employment with the employer. The worker noted on the report hearing protection was provided by the employer when they began their employment and later became mandatory. Further, the worker noted their hearing was tested yearly at work. The worker listed non-occupational exposure to noise including power boating, home power tool operation and noted they hunted annually, possibly shooting 4 to 5 times while hunting and noted they were a right-handed shot. On the Work History Summary also submitted by the worker, they noted exposure for 8 hours per day with their previous employer without hearing protection. With their current employer, the worker indicated 2 to 3 hours of noise exposure per day since they began with the employer in 1986 to the present. The worker noted they did not initially wear hearing protection until it became mandatory. Also provided was a September 1, 2020 audiogram, which noted a notch at the 4,000 Hz level at the left ear and an unremarkable exam for the right ear.

On October 1, 2020, the WCB contacted the worker to discuss their claim and gather further information. The worker confirmed the information on the report and noted in their current position with the employer, they work in a shop 20% of the time repairing items using hand tools and outside of the shop 80% of the time. They also confirmed their exposure to noise for 2 to 3 hours per day. The worker advised they first noticed a gradual decline in their hearing in 2010, with their left ear worse than their right. The worker further confirmed they had yearly hearing tests done by their employer. The WCB advised the worker the threshold for accepting noise-induced hearing loss claims was exposure to noise levels at or above 85 dBA for a minimum period of 2 years, for 8 hours per day and further investigation was required.

The employer provided the WCB with an Employer Hearing Loss Report on October 20, 2020. The report noted the worker started their employment on January 13, 1986 and noted the hearing protection program started in 1999/2000, with hearing protection provided to the worker. The employer provided the worker’s job description and a list of the different positions the worker had during their employment. The employer also provided the WCB with copies of the audiologic testing for the worker from 1991 to 2016, with a significant shift in the worker’s hearing noted during the 2013 testing. An Employer Hearing Loss Report was also received from the worker’s previous employer on November 23, 2020, indicating the worker was exposed to continuous noise from the constant operation of machinery and that hearing protection was available for the worker.

The worker’s WCB adjudicator placed a memorandum to file on December 4, 2020 noting the worker’s previous employers, including the most recent previous employer the worker was employed with between June 1978 and January 1986. With this employer, it was noted the worker was exposed to noxious noise 8 hours per day without hearing protection and industry standard noise levels were noted to be 86 dBA on average. The adjudicator found that the criteria for noise induced hearing loss had been met. The worker’s file was reviewed by the WCB’s Ear, Nose and Throat (ENT) specialist who placed notes to the worker’s file on December 8, 2020 and December 17, 2020. On December 8, 2020, the specialist noted “The June 27, 1991 audiogram shows a dip at 6000 Hz in the right ear and a dip at 4000 and 6000 Hz in the left ear. Although missing the reading for 8000 Hz, it is suggestive of early signs of NIHL (noise induced hearing loss). Based on this audiogram, a hearing aid is not needed for the right ear and the borderline need for a left hearing aid would be on the basis of the worker’s history of right-handed firearm use.”

On December 17, 2020, the ENT specialist opined the earliest audiogram to indicate signs of NIHL in the left ear was the 1991 audiogram, with NIHL in both ears indicated in a 2013 audiogram. The WCB provided the worker with a formal decision letter on December 18, 2020 advising their claim for noise-induced hearing loss was not acceptable as it had been determined a relationship between their hearing loss and their job duties could not be established. On January 7, 2021, the worker provided the WCB with another copy of the September 1, 2020 audiogram and a January 7, 2021 report from their treating ENT specialist, which indicated “The configuration of the audiograms are consistent with noise induced hearing loss from many years of workplace noise exposure” and recommended hearing aids for both ears. On January 11, 2021, the WCB provided the worker with a further decision letter advising the new medical information had been reviewed but there would be no change to the earlier decision their claim was not acceptable.

On January 13, 2021, the worker requested reconsideration of the WCB’s decision to Review Office. The worker advised in their request their treating audiologist and ENT specialist both support the worker’s hearing loss was noise-induced hearing loss related to their employment.

Review Office found on February 1, 2021, the worker’s claim was not acceptable. Review Office agreed with the opinion of the WCB’s ENT specialist that the first audiogram to indicate NIHL for the worker was in 1991 and was for their left ear only. Review Office found that NIHL is typically symmetrical and concluded the worker’s right-handed firearm use could account for the worker’s loss being asymmetrical. In addition, Review Office accepted the opinion of the specialist that the 2013 audiogram was the first indication of bilateral NIHL for the worker and noted the employer had a mandatory hearing protection program in place at that time and as such, the worker’s hearing loss was found to not be related to their employment.

The worker provided detailed information on their job duties to Review Office on February 19, 2021 and requested reconsideration of the earlier decision. The worker noted in their submission, several of their job duties involved hammering metal on metal, with these tasks done for the majority of their day. The worker further noted some of those duties can take several hours to complete.

Review Office again determined on March 15, 2021, the worker’s claim was not acceptable. Review Office acknowledged the new information provided by the worker regarding their job duties and how some of those duties may have exposed their left ear to more noise while at work however, Review Office found that as the evidence provided hearing protection was not mandatory prior to 1999/2000, the worker’s right ear would also not have been protected and would have expected to see evidence of some NIHL in the right ear along the same time as NIHL was first found in the left ear, being 1991. However, NIHL was not indicated in the worker’s right ear until 2013. As such, Review Office determined the worker’s hearing loss was not related to the worker’s employment.

The worker’s representative submitted a June 18, 2021 report from the worker’s treating audiologist on June 30, 2021 and requested Review Office reconsider the previous decision. The audiologist’s report indicated the worker was exposed to noise levels of up to 148 dB while performing job duties including hitting steel with a hammer and noted even with hearing protection in the form of ear plugs, the worker would have been exposed to noise levels of 128.25 dBA, which was above the WCB’s threshold for noise exposure. The audiologist opined the worker’s hearing assessment on October 22, 2020 indicated the worker had a “…moderate high frequency sensorineural hearing loss in the right ear and moderate-severe high frequency sensorineural hearing loss in the left ear.”

The representative presented the argument that the worker had been exposed to noxious noise above the 85 decibels required by the WCB’s policy at 128.25 decibels with hearing protection, and the required exposure time at that decibel level would be less than 1.5 minutes daily, with the worker reporting that job duty taking 10 minutes up to 8 hours per day.

Review Office found the worker’s claim was not acceptable on July 7, 2021. Review Office noted in the information on file from the worker and the employer indicated a hearing protection program was put in place in approximately 1999/2000 and found that as the employer determined a program was needed, the worker’s job duties produced noxious levels of noise. However, Review Office found the employer did not have any sound level assessment conducted for the areas where the worker worked. Review Office again noted the worker’s asymmetrical hearing loss indicated in 1991 and found that when the worker’s NIHL became bilateral in 2013, the employer’s hearing protection program was in place and the worker would have been required to wear appropriate hearing protection. Review Office found it speculative that the employer did not regulate the hearing loss program to reduce the excess noise levels the worker was exposed to.

The worker contacted the WCB on February 24, 2022 to advise they were aware that the employer had conducted noise level testing in all areas, including the job sites they had worked in.

On July 15, 2022, the WCB contacted the employer to request copies of the testing, which was received on July 18, 2022. The WCB provided the worker with a further decision letter on August 25, 2022, advising the noise level testing from the employer established the noise level for their position at 85 dB for a time weighted average of 8 hours however; with the use of hearing protection, the noise exposure would have been reduced to 73.5dB and as such, it was determined their claim was not acceptable.

On October 20, 2023, the worker’s representative submitted additional information and requested Review Office reconsider the earlier decisions that the worker’s claim was not acceptable. The information provided included a report from the worker’s second treating ENT specialist supporting the worker’s previous ENT specialist’s opinion that the worker’s hearing loss was indicative of noise exposure at work, and audiological testing results from areas where the worker worked indicating some of the workers in those areas were exposed to noxious noise levels.

Review Office requested a review of the worker’s file by an audiology consultant, which took place on November 2, 2023. The consultant opined the 1991 audiogram was the first date NIHL was indicated in the worker’s left ear. It was noted with respect to the worker’s right ear that “…hearing thresholds returned to the normal range for multiple assessments from 1995-2002, and again in 2005. As such the loss seen in 1991 was not a permanent hearing loss, with the worker’s exposure to occupational noise ending in 2000. The consultant further provided hearing loss due to noise exposure does not progress when the exposure ends and accordingly, any decline in the worker’s hearing after 2000, would not be attributable to earlier noise exposure. A copy of the consultant’s opinion was provided to the parties on November 27, 2023, with the worker’s representative providing a response on December 7, 2023.

Review Office again determined the worker’s claim was not acceptable on December 12, 2023. Review Office agreed with and accepted the opinion of the WCB audiology consultant and found the worker was exposed to loud noise without hearing protection for a portion of their employment, with asymmetrical NIHL indicated in their left ear in 1991. Review Office found the worker’s hearing, including the asymmetrical left ear NIHL, did not change for multiple years and determined that had the worker been exposed to ongoing noxious noise, there would have been some change to either the asymmetrical loss or the loss would have become bilateral. In addition, Review Office found the worker’s hearing loss in the right ear occurred many years after the implementation of a hearing loss protection program by the employer.

The worker’s representative filed an appeal with the Appeal Commission on February 15, 2024 and a hearing was arranged.

Reasons

Applicable Legislation and Policy

The panel is bound by The Workers Compensation Act (“the Act”), regulations under the Act, and policies established by the WCB's Board of Directors. The provisions of the Act in effect as of the date of the worker's accident are applicable.

A worker is entitled to benefits under subsection 4(1) of the Act where it is established that the worker was injured as a result of an accident at work.

The Act defines "accident" as a chance event occasioned by a physical or natural cause; and includes

(a) a wilful and intentional act that is not the act of the worker, 

(b) any 

(i) event arising out of, and in the course of, employment, or 

(ii) thing that is done and the doing of which arises out of, and in the course of, employment, and

(c) an occupational disease,

and as a result of which a worker is injured.

The WCB's Board of Directors has established Policy 44.20.50.20, Noise-Induced Hearing Loss, (the "NIHL Policy"). The NIHL Policy outlines the WCB's approach to claims arising from long-term exposure to occupational noise that causes hearing loss.

The NIHL Policy provides that a

“claim for noise-induced hearing loss is accepted by the WCB when a worker was exposed to hazardous noise at work for a minimum of two years, based generally upon an average of 85 decibels for 8 hours of exposure on a daily basis. For every increase in noise level of 3 decibels, the required exposure time will be reduced by half”.

It goes on to state:

“Permanent hearing loss can be caused either by a workplace event (trauma or a single exposure to occupational noise) or prolonged exposure to excessive noise. This policy applies to claims arising from long-term exposure to occupational noise that causes hearing loss. These claims are called noise-induced hearing loss claims.”

Worker’s Position

The worker appeared in the hearing represented by a worker advisor. The worker advisor made an oral submission on behalf of the worker, and the worker provided testimony in answer to questions posed by the worker advisor and by members of the appeal panel. Written submissions from the worker and the worker advisor were also provided to the panel.

The worker’s position is that the evidence confirms that the worker was exposed to noxious noise in the workplace and developed NIHL as a result of that exposure, which was noted as early as 1991. As such, the worker’s claim should be accepted.

The worker advisor outlined that the worker had been employed as a machinist with their first employer from 1977 to 1986, and later as an industrial mechanic and millwright for a second employer from 1986 until their retirement in 2020. In the early years of their employment, the worker did not wear hearing protection.

The worker testified to the nature of their work and the circumstances when they needed to use hearing protection during the years it was required and provided. The worker confirmed that they used ear plugs and earmuffs and began doing so around 1999. However, the worker repeatedly stated that it was only in the last ten years, when a new safety administrator was appointed, that they strictly adhered to their employer’s safety program.

The worker advisor noted that the earliest audiogram to show signs of NIHL in the left ear is dated 1991. The earliest audiogram to show signs of NIHL in both ears is dated 2013.

The worker advisor also relied on a June 18, 2023 audiologist report which provides an opinion that the worker’s noise exposure is a consequence of hitting steel with a hammer which can have noise levels up to 148dBA. Furthermore, the report goes on to state that when the worker is wearing hearing protection, they are still being exposed to noise levels of up to 128.25dBA which is still able to damage the worker’s hearing.

In sum, the worker’s position is that the evidence supports a finding that the worker’s hearing loss, more likely than not, arose out of and in the course of the worker’s employment and as such, the claim should be acceptable.

Employer's Position

The employer did not participate in the appeal.

Analysis

The issue on appeal is whether the claim is acceptable. To find that the claim is acceptable, the panel would have to determine that the worker has hearing loss, that is, on the balance of probabilities, the result of exposure to noise in the workplace. The panel was not able to make such a finding based on the evidence and arguments before us.

The panel adheres to commonly accepted principles in evaluating claims for occupational NIHL. The panel accepts that a primary characteristic of occupational NIHL is that it is symmetrical in both ears. An additional guiding principle is that hearing loss from noise exposure does not typically progress once such exposure is discontinued. The panel also recognizes that not all hearing loss is caused by or the result of noise exposure in the workplace. Further, not all workers experience hearing loss from such workplace noise exposure.

The panel carefully considered the testimony of the worker, and reviewed the available audiograms on file. The worker testified that there have been no discernible changes to the kind of work that they carried out as a millwright and as an industrial mechanic since 1986. There was no evidence presented that would suggest a material increase in the intensity of occupational noise that the worker was exposed to.

The worker testified that for the first ten or so years of his employment, they typically did not wear hearing protection, and that it was only when the appointment of their employer’s Safety Officer on or about 2010, that implementation of safety protocols and hearing protection was strictly enforced.

Despite the relatively stable noise conditions in the worker’s work environment, and the increased usage of hearing protection since 2010, the worker’s audiograms evidence hearing loss throughout the years. However, the evidence presented to the panel does not suggest that the worker’s hearing loss arose from his employment.

The baseline levels from available audiograms on file are from a 1991 audiogram. From the 1991 audiogram, signs of hearing loss in the left ear is recorded. However, from the period of 1991 to 2005, the worker’s hearing improved. There is no evidence presented to the panel that the left ear hearing loss is due to their employment, and the improvement recorded in the audiograms appears to suggest the loss was temporary.

Furthermore, the audiograms disclose a fluctuation between the normal and mild hearing loss range from 1995 to 2002, and again in 2005. It appears to the panel in general, that for this period of time, non-noise induced hearing loss was fairly consistent.

No work-related explanation was presented to the panel as to why the worker’s hearing deteriorated in 2013 and 2014, and why the worker’s hearing level returned to baseline in 2015.

There is no viable explanation presented to the panel as to why the worker’s hearing deteriorated in the last decade of his employment. The worker’s own admission was that no material change occurred in the type of work that they carried out, and that in the last ten years of his employment, his workplace saw a stricter adherence to hearing safety.

As it pertains to noise exposure at work, the worker advisor relies primarily on the June 18, 2023, audiologist report which provides an opinion that the despite the worker wearing hearing protection, the worker is still being exposed to noise levels of 128.25dBA, as the report alleges, that “the consequence of hitting steel with a hammer can have noise levels up to 148dBA”. However, the June 18, 2023, audiologist report provided no data or explanations as to how noise levels were measured. The panel places less weight on this report.

The panel prefers the evidence from the employer’s Noise Level Hazard Assessment, which it conducted on October 5, 2021. This report was conducted after the worker’s retirement. The noise assessment documented the noise levels in the locations where the worker would ordinarily perform his work. Measuring devices were placed on test subjects working on the same tasks as the worker. The noise assessment revealed a dosimeter reading of 85 decibels (dBA). With the use of hearing protection, the worker’s exposure to noxious levels of noise would have been reduced to below the 85-decibel requirement as per the NIHL Policy.

While there is evidence of the worker’s current condition of a moderate high frequency sensorineural hearing loss in the right ear and moderate-severe high frequency sensorineural hearing loss in the left ear, the panel is unable to link the noise exposure from work and the worker’s claim of hearing loss given the findings from the noise assessment.

The panel is not able to establish that the worker’s hearing loss is the result of noise exposure at work. The medical evidence here indicates that there was a possibility that there was a NIHL component to the worker’s hearing loss in their left ear, however, such a finding would not be consistent with the principal that occupational NIHL is symmetrical, unless there is a reason for the asymmetry. Furthermore, the continued degradation of the worker’s hearing from 2013 is also inconsistent with the principle that hearing loss does not progress once noise exposure is discontinued.

The panel finds that the worker's right ear hearing ranges were considered to be normal during periods of time they were exposed to loud working environments, and not utilizing hearing protection (i.e. from 1995 to 2005). The panel is also of the opinion that the decline seen in their right sided hearing around 2013 is not related to, nor caused by, his exposure to occupational noise.

As such, while the panel accepts that the worker has hearing loss, we are unable to determine based on the evidence before us and on the standard of a balance of probabilities that this hearing loss is the result of their workplace exposure to noise. We therefore conclude that the claim is not acceptable, and the worker’s appeal is dismissed.

Panel Members

R. Mamucud, Presiding Officer
J. Peterson, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

R. Mamucud - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 16th day of August, 2024