Decision #95/21 - Type: Workers Compensation

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("WCB") that his claim is not acceptable. A videoconference hearing was held on May 27, 2021 to consider the worker's appeal.

Issue

Whether or not the claim is acceptable.

Decision

That the claim is not acceptable.

Background

The worker filed a Worker Hearing Loss Report with the WCB on September 12, 2019, reporting a loss of hearing which he attributed to his employment with "…five employers in industrial settings." The worker noted that his hearing loss came on gradually and that he used hearing protection in the form of ear plugs and ear muffs at different times "off and on for 30 years." The worker provided a Work History Summary, listing his employers from 1975 to 2015, and noted that in the period of employment from 2003 to 2009 "…some hearing loss showed up" during testing.

On September 17, 2019, a WCB adjudicator contacted the worker to review his claim. The worker confirmed the details of his job duties, the machinery and tools he used, his exposure to noise and the use of hearing protection for each of the employers listed on the Work History Summary. The adjudicator explained the WCB's criteria for a hearing loss claim to be acceptable and advised that an audiogram consistent with noise exposure would be required.

On September 19, 2019, the worker attended for an audiological assessment. Following that assessment, the attending audiologist opined that the worker had sustained a bilateral sensorineural hearing loss and had "…been exposed to industrial noise for many years."

The employer filed an Employer Hearing Loss Report with the WCB on December 17, 2019, noting the worker had been employed by them from October 2002 to March 2008. The employer provided an audiometric history for the worker, with annual test results from 2002 to 2006, and noted that the worker's pre-placement audiogram from October 2002 had shown an abnormal baseline. The employer advised that the worker performed his job duties in a location with noise levels from 82 to 86.8 dBA, and provided an ambient noise survey map of the employer's plant indicating the noise levels in different areas of the facility. The employer further confirmed that they had implemented a noise protection program in 1985 and that the worker had been provided with protective hearing devices in the form of foam ear plugs throughout his employment with them.

In a note to file dated December 18, 2019, the worker's WCB adjudicator indicated that based on the information provided by the employer, the worker would not have been exposed to sufficient noxious noise levels to meet the minimum WCB threshold. The adjudicator further indicated that she would have the WCB's ear, nose and throat ("ENT") consultant review the October 8, 2002 baseline audiogram to determine if the worker's hearing loss at that time was consistent with noise-induced hearing loss ("NIHL").

On December 22, 2019, the WCB's ENT consultant reviewed the 2002 audiogram and opined that "The 2002 audiogram shows normal hearing thresholds in both ears except for a dip at 6000 and 8000 Hz in the right ear and 8000 Hz in the left ear. This configuration is not typical or diagnostic of NIHL."

On December 23, 2019, the WCB's Compensation Services advised the worker that his claim for NIHL was not acceptable as they were unable to relate his hearing loss to the performance of his job duties. Compensation Services determined that the available information did not establish work-related exposure to noise that met the WCB's minimum threshold requirement for a claim for NIHL. Compensation Services further determined that the worker's employment prior to 2002 could not be considered, as the information on file indicated his hearing was within normal thresholds and there was no hearing loss at that time.

On August 10, 2020, the worker requested Review Office reconsider Compensation Services' decision. The worker noted that some of the information provided by the accident employer was incorrect. The worker noted, in particular, that he worked in a different building from the one the employer had indicated, where the noise level was much higher, averaging 95 decibels in his primary area of employment. The worker also disagreed with Compensation Services' use of the 2006 audiogram results, noting he worked two more years for the accident employer and a post-employment audiogram was never conducted. The worked submitted that the 2006 results were not representative of his hearing loss when he left that employment in 2008.

On September 22, 2020, Review Office determined that the worker's claim was not acceptable. Review Office acknowledged the worker's statement that he worked at a location with higher noise levels, but found that the evidence did not support he was exposed to the levels of noxious noise which were required to satisfy the minimum criteria for acceptance of an occupational NIHL. Review Office also accepted the opinion of the WCB's ENT consultant that the test results in the 2002 audiogram were not typical or diagnostic of NIHL, and found that occupational NIHL was not indicated in the test results through to 2006. Review Office further stated that they were unable to give weight to the worker's 2019 test results as the evidence did not indicate he was exposed to noxious noise at work which would account for the findings of that audiogram.

On January 14, 2021, the worker appealed the Review Office decision to the Appeal Commission and a videoconference hearing was arranged.

Reasons

Applicable Legislation and Policy

The Appeal Commission and its panels are bound by The Workers Compensation Act (the "Act"), regulations and policies of the WCB's Board of Directors.

Subsections 1(1) and 4(1) of the Act set out the circumstances under which claims for injuries can be accepted by the WCB, and state that the worker must have suffered a "personal injury by accident arising out of and in the course of" employment. Once such an injury has been established, the worker is entitled to the benefits provided under the Act.

With respect to claims for hearing loss, the injury can be caused by either a workplace event (trauma or a single exposure to occupational noise) or prolonged exposure to excessive noise. The worker's claim has been advanced on the basis of long-term exposure to noxious levels of occupational noise resulting in NIHL.

WCB Policy 44.20.50.20, Noise-Induced Hearing Loss (the "Policy"), outlines the WCB's approach to claims arising from long-term exposure to occupational noise causing hearing loss, where the date of notification of the claim is on or after October 1, 2013. The Policy states, in part, that:

Not all hearing loss is caused by exposure to noise at work. 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.

Worker's Position

The worker was self-represented and provided a written submission in advance of the appeal. The worker was accompanied by his spouse at the hearing. The worker made an oral presentation and responded to questions from the panel.

The worker's position was that the evidence on file and as submitted prior to and at the hearing supported that he has a NIHL and his claim should be accepted.

The worker stated that he did not know how the WCB could question whether he met the applicable criteria. The worker noted he worked in the same building, in a compressor room, for 20 years, the last five of which were with the accident employer. The worker referred to a 2012 noise survey map of that building from the accident employer, which he had provided in advance of the hearing and which showed that the sound level in the compressor room averaged 95 decibels.

The worker submitted that he also did some maintenance work in the building, a lot of which was noisy work and included using sledgehammers.

The worker relied on a December 24, 2020 letter from his audiologist which he had filed prior to the hearing and in which the audiologist stated that he believed the worker's hearing loss was NIHL. The worker noted that the audiologist also provided a link in his letter to an online research study which implicated chronic noise exposure in the acceleration of age-related hearing loss, and asked that the panel take that into consideration when adjudicating his appeal.

Employer's Position

The employer did not participate in the appeal.

Analysis

The issue on this appeal is whether or not the claim is acceptable. For the appeal to be successful, the panel must find, on a balance of probabilities, that the worker sustained a NIHL during the course of his employment due to exposure to high levels of noxious noise as set out in the Policy. The panel is unable to make that finding, for the reasons that follow.

The Policy provides that not all hearing loss is caused by exposure to noise at work. The Policy further sets out the criteria which must be met in order to establish that a NIHL occurred at work.

Based on our review of all of the information which is before us, the panel accepts that the worker worked in a noisy environment and was exposed to loud noise at work. The panel also accepts that the worker has hearing loss. The panel is unable, however, to connect the worker's hearing loss to his employment. In particular, the panel is unable to find that the available medical information supports that the worker suffered NIHL as a result of his exposure to any such workplace noise.

In this regard, the panel places weight on the opinion of the WCB ENT consultant who stated on December 22, 2019 that the configuration in the 2002 audiogram was "not typical or diagnostic of NIHL."

The panel is satisfied that the worker's audiometric test results from 2002 to 2006 are also not consistent with NIHL. It is the panel's understanding that test results which indicate NIHL have a unique "reverse checkmark" type of configuration, with a typical notch around the 4000 Hz level which is characteristic of that kind of hearing loss. The panel notes that such a pattern or configuration does not appear to be present in the worker's 2002 to 2006 test results. The panel further notes that the worker was not diagnosed with NIHL in respect of those years.

The worker indicated that he worked in the same building and the same compressor room for another employer for 15 years prior to 2002, but that no hearing tests were performed during that period of time. Given that the 2002 audiometric test results indicate, however, that the worker did not have NIHL at that time, the panel is unable to find that the worker had developed NIHL prior to that date.

The worker further suggested that it was significant that he did not have a hearing test prior to leaving his employment with the accident employer in 2008. The panel finds, however, that there is no indication that anything had changed in terms of the worker's hearing as at that date.

The panel notes that the worker's next hearing assessment was not until September 3, 2019, when the attending audiologist opined that the worker had sustained a bilateral sensorineural hearing loss. The panel is unable to relate the results of that assessment and the audiologist's opinion to the worker's employment with the accident employer more than 11 years previously or to his employment subsequent to 2008.

While the worker also relied at the hearing on the December 24, 2020 letter of support from his treating audiologist, the panel is unable to place much weight on that letter. The panel notes that the audiologist commented, in part, that:

Clinical research suggests that exposure to chronic occupational noise above 85 dBA for several years can have the effect of synergistically interacting adversely with age-related hearing loss. In other words, excessive noise exposure can accelerate the progress of age-related hearing impairment in later life. Given [the worker's] current audiometric pattern, it seems conceivable that his early occupational noise exposure could have played a central role in the severity of his current hearing loss beyond what age would produce alone. The extent to which his noise exposure deleteriously influenced the progression of the age factor would be difficult to disambiguate or discern, but I do believe this possibility is worth considering in re-evaluating his case for benefits. Chronic noise exposure can produce subclinical cochlear synaptic and auditory nerve injury that may not manifest audiometrically until age effect sets in later in life. I am speculating that during the screening years of 2002-2006, there may possibly have been noise-induced cochlear injury that wasn't overtly evident on the audiograms, but may be clinically and functionally consequential as he is aging into seniorhood. (Italics added)

The panel finds that, as indicated in the above passage, the audiologist's comments or opinion as to the late onset of the worker's hearing loss, or the worker's hearing loss being partly or possibly due to earlier exposure to workplace noise, are speculative, and do not meet the standard of a balance of probabilities which applies in this case.

The panel also considered the online study which was referred to by the audiologist in his December 24, 2020 letter, but is unable to place much weight on that study. The panel notes that the study provides certain general findings, but there is a lack of any indication that these are accepted by the larger medical community, and the panel is unable to relate such findings to the worker's case or a diagnosis of NIHL.

Based on the foregoing, the panel is unable to find that the worker's hearing loss and ongoing hearing problems were causally related to his work or job duties. The panel therefore finds, on a balance of probabilities, that the worker did not sustain a NIHL during the course of his employment due to exposure to high levels of noxious noise as set out in the Policy, and the worker's claim is not acceptable.

The worker's appeal is dismissed.

Panel Members

M. L. Harrison, Presiding Officer
J. Peterson, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

M. L. Harrison - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 26th day of July, 2021

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