The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("WCB") that their claim is not acceptable. A hearing was held on December 15, 2021 to consider the worker's appeal.

Issue

Whether or not the claim is acceptable.

Decision

The claim is not acceptable.

Background

The worker filed a Worker Hearing Loss Report with the WCB on November 1, 2019, reporting gradual hearing loss that they attributed to their 35-year employment with the employer. The worker reported first noting their loss of hearing approximately 15 to 20 years previous via regular hearing tests done by the employer. The worker also reported wearing hearing protection through their whole career with the employer.

On November 13, 2019, the WCB contacted the worker to obtain further information about the claim. The worker confirmed they noticed gradual hearing loss some 15 – 20 years earlier and that they believed the employer was aware of this, as the employer conducted regular hearing tests for their employees. Further, the worker confirmed they wore hearing protection during the whole time they were employed and noted minimal exposure to noise outside of work. The worker confirmed they had their hearing tested on January 25, 2019.

The WCB requested and received a copy of the January 25, 2019 audiogram, which indicated "…a normal to moderate sensorineural loss on the right and a normal to mild sensorineural hearing loss on the left."

On December 12, 2019, the employer provided the WCB with the Employer Hearing Loss Report, noise level testing results, information on their hearing testing program and the type of protection worn by the worker, as well as copies of the worker's audiograms conducted in 1999, 2002, 2004, 2009 and 2011 and copies of 23 tests conducted on the worker between 2013 and 2018 regarding proper use of personal protection equipment.

The WCB adjudicator reviewed the information and noted to the worker's file on January 16, 2020 the worker's advice that they had not worn hearing protection consistently until approximately the last five years of their employment when use of hearing protection was mandatory. The adjudicator also noted the noise levels provided by the employer for the area of the worker's job site ranged from 77.5 to 92.5 dBA.

On January 29, 2020, a further hearing assessment conducted by a certified audiologist indicated the worker has "…a moderate high frequency sensorineural hearing loss for the right ear and a mild high frequency sensorineural loss for the left ear."

A WCB Ear, Nose and Throat (ENT) specialist reviewed the worker’s file on January 30, 2020 and concluded that noise induced hearing loss was first indicated on an October 9, 2002 audiogram in the worker's right ear. The ENT specialist stated "The worker has an asymmetric hearing loss with the right ear being worse. Based on the bone conduction testing, the hearing thresholds are within the normal range in the left ear and the configuration is consistant (sic) with warning signs of NIHL (noise induced hearing loss)."

The WCB contacted the worker on February 11, 2020 for further information regarding the asymmetric hearing loss. The worker provided further detail about their job duties but could not provide an explanation for the greater loss of hearing in their right ear.

On February 12, 2020, the WCB advised the worker that the evidence confirmed exposure to noxious noise during their employment with the employer. Further, the evidence supported a finding of NIHL in their right ear in 2002 but only warning signs of NIHL in their left ear. But, Review Office found that as occupational noise induced hearing loss is normally bilateral and symmetrical, a relationship between their hearing loss and job duties could not be established and therefore the claim was not acceptable.

The worker requested reconsideration of the decision to Review Office on February 28, 2020, indicating the treating audiologist advised that the fact the worker is right-hand dominant and used tools in their right hand would explain why their hearing loss was worse in their right ear. On April 30, 2020, the employer provided a submission in response to the worker's request, noting the worker participated in a noise exposure study in 2015 that indicated with hearing protection used the worker’s maximum workplace exposure to noise was 78.5 dBA. Further, the employer provided photographs of workers using similar power tools as the worker would have used and noted the tools were used in front of the worker, not at their side, and as such, the noise exposure would have been to both ears equally resulting in bilateral noise exposure. The WCB provided the employer's submission to the worker on May 4, 2020 and the worker provided a response on May 8, 2020, noting the photographs the employer provided depicted smaller power tools, but the power tools the worker used were generally larger than those shown on the photographs and were used in a different manner.

Review Office determined on May 14, 2020 that the worker's claim was not acceptable. Review Office noted the worker's description of how they used the equipment would not have exposed the worker's right ear to significantly more noise than the left and did not provide an explanation for the worker's hearing loss being greater on the right. Further, Review Office noted the worker's audiograms first indicated right ear NIHL in 2002, and the worker had essentially normal hearing in their left ear until 2020, after their retirement in 2019. Review Office found that some hearing loss would have been expected in the worker's left ear; however, no such loss was indicated on the audiograms.

The worker's representative filed an appeal with the Appeal Commission on August 16, 2021. A hearing was arranged for December 15, 2021.

Reasons

Applicable Legislation and Policy

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

Section 4(1) of the Act provides that where a worker suffers personal injury by accident arising out of and in the course of employment, compensation shall be paid. The Act defines “accident” in s 1(1) as follows:

"accident" means 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 "Policy"), which provides, 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 appeared at the hearing represented by a worker advisor, who made a submission on behalf of the worker. The worker offered evidence through answers to questions posed by the worker advisor and by appeal panel members.

The worker’s position, as outlined by the worker advisor, is that the hearing loss demonstrated by the audiological reports in the file is the result of exposure to noise in the workplace and therefore the claim should be accepted. The worker advisor provided that the findings of asymmetrical hearing loss can be explained by a combination of the worker’s handedness and their specific workplace exposures to noxious noise.

The worker advisor noted that the audiological testing results confirm the worker’s right ear hearing loss as early as 2002 and left ear hearing loss from 2019. The worker indicated that they first became aware of their hearing loss at least 15 years ago as others would make comments to the worker about not hearing them. The worker confirmed that they did not undergo any hearing testing between 2011 and 2019. The WCB ENT specialist confirmed the worker’s NIHL in the hearing assessment memo dated January 30, 2020 which sets out that the “…worker has an asymmetric hearing loss with the right ear being worse. Based on the bone conduction testing, the hearing thresholds are within the normal range in the left ear and the configuration is consistent with the warning signs of NIHL.”

The worker advisor argued that the correct application of the Policy requires a finding that the worker’s claim is acceptable when there is workplace exposure to noise above the threshold set out in the Policy and there evidence of noise induced hearing loss. As set out in the January 16, 2020 file note, the WCB case manager determined that the worker was exposed to noxious workplace noise based upon the evidence provided by the employer. This was further confirmed in a memorandum to file from the case manager dated February 11, 2020, based upon further information the worker provided at that time and in the WCB’s letter to the worker of February 12, 2020.

With respect to the asymmetry of the worker’s hearing loss, the worker advisor outlined the worker’s position that this is due to their right handedness and associated body positioning when using power tools in the course of their work. The worker advisor pointed the panel to consider the January 20, 2021 opinion of the treating ENT specialist who stated that the worker:

“…has a high tone hearing loss similar to that seen with acoustic trauma. It is worse in the right ear. It is possible that the right ear may have been more affected due to the work space that [the worker] was involved with….My feeling is this is a noise induced hearing loss which has affected [the worker’s] right ear more so.”

The worker advisor urged the panel to accept the “head shadow effect” as a potential explanation for the worker’s asymmetrical hearing loss, stating that the impact of noise exposure is greatest on the side nearest the noise source. In the worker’s case, given their right handedness, the worker’s right ear would have been nearer to any power tools used in their work and as explained by the worker to the panel, the primary sources of ambient noise in the workplace were located to the right and forward or behind their workstation. The worker testified to the panel as to where the noise sources were located in relation to their position while working, noting that when using heavy power tools they would lean into the tool with their body weight for stability, leaning to the right while operating the tools at hip to waist height. The worker confirmed that their use of such tools continued into 1999 but that from 2000 onwards, their job involved controlling a machine from a control panel, with very noisy hydraulic equipment located 8 – 15 feet to the right of the worker’s location. In addition, the worker noted they were exposed to significant ambient noise from other sources including employee radios at various workstations through the building.

The worker confirmed their retirement date of February 1, 2019 and noted that they insisted upon a hearing test being conducted before that date. This test took place on January 25, 2019 as outlined in a letter of November 14, 2019 from the testing practitioner to the WCB.

The worker indicated to the panel that outside of work, they engaged in hobbies that did not expose them to noxious noise. With respect to the shooting activity noted on file, the worker explained that as a child they took part in some target shooting with their father, using a .22 caliber rifle, but had not done so since then.

In sum, the worker’s position is that their bilateral, asymmetric hearing loss is the result of their exposure to noxious noise in the workplace over the course of some 35 years of employment with the employer and therefore, the claim should be accepted.

Employer’s Position

The employer did not participate in the appeal.

Analysis

The issue on appeal is whether or not the claim is acceptable. For the panel to find that the claim is acceptable, it would have to determine that the worker’s hearing loss is the result of exposure to noise in the workplace. The panel was not able to make such a finding for the reasons that follow.

While the evidence supports that the worker now has bilateral sensorineural hearing loss and that there was a history of workplace noise exposure, not all hearing loss is caused by or the result of noise exposure in the workplace. Further, not all workers experience hearing loss as a result of such noise exposure.

In this case, the employer provided noise level exposure information to the WCB including noise level studies from 2016 for the worker’s position at their specific workplace which indicate average exposure of 92.5 dBA over 8 hours, increased to 101.5 to 107.5 dBA while using certain tools. Further, the employer provided a summary of noise level measurement from 2003 that indicated a range for the worker’s position of 84.9 – 103.9 dBA, and an average of 91.3 dBA. The employer further confirmed the worker’s appropriate personal protective equipment on 21 tests conducted between 2013 – 2018. The employer also provided noise monitoring evidence for the worker’s workplace set out in a report dated January 22, 2015 that sets out the average exposures as ranging from 84.1 – 89.6 dBA before taking into account hearing protection used. In the submission of April 30, 2020 to Review Office, the employer outlined the tempering effect of using hearing protection based on the highest average noise level for employees in the worker’s job description of 92.5 dBA and based on the highest average personal noise exposure level from the 2015 study, of 85.7 dBA. Based upon this information, the worker’s maximum average noise exposure wearing hearing protection would have ranged from 71.7 – 78.5 dBA.

The panel noted that although the worker initially set out in their claim that they consistently used hearing protection through all their working years with the employer, on further questioning by the WCB adjudicator, the worker indicated that their use of hearing protection was not consistent until the last five years of work. In offering testimony during the hearing, the worker stated that they did not use hearing protection much as an apprentice, but in later years wore hearing protection plugs most of the time. The worker’s testimony before the panel suggested that they would remove their plugs as required to communicate in the workplace, but generally wore them while working.

The WCB initially determined that the worker was exposed to noise levels above the minimum threshold required by the Policy and the Review Office accepted this finding, but the panel finds that the evidence supports that the worker’s average workplace noise exposure would have been tempered by the worker’s use of hearing protection in the course of their work. On the basis of the noise level study evidence in the worker’s file and the information provided by the worker, we agree that the worker was exposed to noise levels above the threshold average of 84 dBA for 8 hours daily, but we also accept the worker’s evidence that they generally used hearing protection through their years of employment, although less consistently in their early years. Taking the use of hearing protection into account, the panel is not satisfied that the workplace noise exposure was sufficient to exceed the threshold set out in the Policy.

Further, the panel also considered that generally, noise induced hearing loss due to workplace noise exposure is symmetrical. The worker’s position is that as a result of the noise exposure over the course of their 35-year employment, they developed NIHL at first in the right ear, evident from 2002, and later in the left ear, beginning in 2019. The panel noted the treating ENT specialist offered an explanation for the lack of symmetrical findings, that “It is possible that the right ear may have been more affected due to the work space that [the worker] was involved with.” The panel considered this opinion, in light of the worker’s testimony and submissions. We note that the treating ENT specialist has not provided any more specific occupational explanation for the asymmetry in the worker’s hearing loss other than referencing that the worker is right-handed and making a general comment about the possible impact of the workspace. The panel heard the worker’s detailed descriptions of their work environment and positioning when undertaking their job duties. We are not satisfied by the explanations offered that the worker’s right handedness and body positioning when using power tools through 1999 accounts for the asymmetrical development of hearing loss in the subsequent years, nor are we satisfied that the ambient noise emitted by the operation of loud machinery situated at some distance from the worker’s position, after 2000 accounts for this asymmetry. We find that the offered occupational explanations do not adequately account for the worker’s right ear hearing loss from 2002 with normal left ear hearing until 2019.

On the basis of the evidence reviewed and heard and on the standard of a balance of probabilities, the panel is unable to establish that the worker’s asymmetrical, sensorineural hearing loss is the result of their workplace exposure to noise. We therefore conclude that the claim is not acceptable.

The worker’s appeal is dismissed.

Panel Members

K. Dyck, Presiding Officer
J. Peterson, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

K. Dyck - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 11th day of January, 2022