Decision #52/15 - Type: Workers Compensation
Preamble
The worker is appealing the decision made by the Workers Compensation Board ("WCB")that his claim for noise induced hearing loss was not compensable. A hearing was held on April 10, 2015 toconsider the matter.
Issue
Whether or not the claim for noise induced hearing loss isacceptable.
Decision
That the claim for noise induced hearing loss is notacceptable.
Decision: Unanimous
Background
In July 2012, the worker filed a claim with the WCB for noise induced hearing loss ("NIHL") which he attributed to his employment as a locomotive engineer. The worker reported that his hearing loss came on gradually and that he first became aware of a hearing problem approximately 7 to 10 years ago.
On September 12, 2012, the worker provided the WCB with the following information:
- he has intermittent ringing in his left ear only. He mentioned it to company doctors at the time of his annual physical.
- his left ear problem was related to the deadman whistle in the yard engines. The whistle was located under the seat and it goes off when he takes his foot off the pedal. It was a safety device on yard engines only.
In a letter dated September 20, 2012, the employer provided the WCB with a job description related to the job duties of a yardman. The employer noted that hearing protection was provided to all employees in the early 1970s but it was unknown whether the worker used them.
The WCB obtained audiogram and MRI results related to the worker's hearing loss which were reviewed by a WCB ear, nose and throat ("ENT") consultant on March 24, 2013. The ENT consultant noted that the 1995 audiogram showed normal hearing in both ears and that subsequent audiograms showed progressive sensorineural hearing loss in the left ear only. The hearing in the worker's right ear remained normal until the last audiogram in 2012. This was a progressive unilateral sensorineural hearing loss. He stated that occupational NIHL was usually bilateral and symmetrical and that the MRI ruled out the possibility of an acoustic neuroma.
On May 15, 2013, the worker noted that his right ear was pointed towards the window so it was not exposed to as much noise as his left ear. He was a yard engineer for 25 years and was exposed to noise from the deadman whistle. This was put in place so engineers did not fall asleep while driving the train. The whistle was directly under the left hand side of the chair. When you take your right foot off the pedal, a piercing loud whistle would blow to wake you up. It would go off several times a shift and he would try to cover his left ear when he knew the whistle would sound as it was a very high piercing noise.
On September 10, 2013, a WCB adjudicator indicated that she discussed the worker's claim file with the WCB ENT consultant. She stated:
According to audiograms, the worker has had normal hearing in both ears up to 1995. He has been employed with [accident employer] from 1979 to 2013.
Between 1995-1997 something happened in the left ear. The first change for the left ear was noted in 1997 and the audiogram configuration is not typical of noise induced hearing loss. There are many nonoccupational causes for example viral, autoimmune system, vascular issues etc which may have caused a difference in the left ear.
We reviewed the worker's job duties and noise exposure at [accident employer]. Based on this information, the worker's hearing loss should have been symmetrical in both ears. It could not be determined there was more noise exposure on the left side than the right side to account for the significant difference in his left ear.
On September 10, 2013, the worker was advised that his claim for NIHL was not compensable based on the following rationale:
Audiogram findings noted that you had normal hearing in both ears until 1997. At that time, there was a change in your left ear and the configuration of the audiogram was not indicative of noise induced hearing loss. Further audiograms noted changes to your left ear where your right ear had normal findings.
Information was obtained from you and your employer with regard to your noise exposure at work. Noise induced hearing loss is symmetrical in both ears. It was determined that your work environment would have exposed both ears to the same noise exposure. As the configuration of the audiogram for your left ear is not typical for noise induced hearing loss and your right ear has normal findings, we are unable to determine a work related cause for your left hearing loss. Therefore this claim for hearing loss has been denied.
On January 10, 2014, the worker appealed the September 10 decision to Review Office.
On March 14, 2014, Review Office confirmed that the claim was not acceptable. Review Office stated:
The worker's explanation for the one-sided hearing loss is the instrumentation configuration of the cabs in the locomotives he operates. He argues that the positioning of a radio loudspeaker and some brake valves would conduct sound directly to his left ear, with his body possibly shielding noise to his right ear.
...Review Office is unable to draw this conclusion given the closed environments of locomotive cabs and the nature of sound transmission. It is simply not probable given the hard surfaces shown in the pictures provided by the worker that loud noises would be "baffled" by the worker's body as he suggests in his appeal.
There is a mention from the worker on file that engineers typically have worse hearing in their left ears than their right, however this statement is not substantiated by evidence and thus given no weight by this office.
In conclusion, while the worker has provided evidence that would support the existence of sufficient environmental noise exposure that could lead to hearing loss, there is insufficient evidence it caused an injury or occupational disease as required by the Act to accept his claim.
On January 13, 2015, the worker appealed Review Office's decision to the Appeal Commission and an oral hearing was arranged.
Reasons
Applicable Legislation
In considering this appeal, the panel is bound by The Workers Compensation Act (the “Act”), regulations and policies of the Board of Directors.
Under subsection 4(1) of the Act, where a worker suffers personal injury by accident arising out of and in the course of employment, compensation shall be paid to the worker by the WCB.
Claims for hearing loss due to exposure to noise in the workplace are adjudicated pursuant to WCB Policy 44.20.50.20, Noise-Induced Hearing Loss. The policy states that noise induced hearing loss occurs gradually and may not involve a loss of earnings. The policy notes that not all hearing loss is caused by exposure to noise at work and sets the threshold for acceptance of a NIHL claim by the WCB as exposure 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.
Worker's Position
The worker was represented by his union representative. The worker answered questions from the panel.
The worker representative referred to WCB Policy 44.20.50.20.01, Hearing Loss. He noted that the policy does not state that there must be symmetrical hearing loss in both ears for a claim to be accepted. He said the worker is not exposed to noise in other aspects of his life and that the only explanation for the worker's hearing loss is the effect of noise exposure at work.
The worker's representative noted the report of the worker's audiologist and the article which she provided dealing with asymmetrical hearing loss. He also noted the March 12, 2013, opinion of the specialist in Rhinology and Endoscopic Sinus Surgery, who found that the worker's "...asymmetric sensorineural hearing loss is not due to retrocochlear pathology, and it is very likely that it represents work-related noise-induced hearing loss, particularly in that ear, working as a train operator (he describes that for many years, the whistle was on the left side of the train, exposing the left ear to far more noise than the right)."
The worker submitted that his hearing loss is due to his job as a locomotive engineer. He said his hearing loss is worse in his left ear due of the proximity of the radio and whistle to the left ear. He described the cabin that he works in, including the locations of the radio and whistle. He said that the whistle causes a high pitched noise and is frequently blown. The radio is next to his left ear and is almost continuously running. He thinks the radio is the main problem.
The worker's representative advised there is also an air exhaust sound caused by the brakes. He said the only change to the brakes has been to vent the air through the floor.
The worker reviewed other duties he performed prior to becoming an engineer and also the difference between working in the yard and on the road. He advised that he has been a road engineer since 2007.
Employer's Position
The employer was represented by its WCB specialist who advised that the employer agrees with the WCB Review Office decision. She agreed with the Review Office that the asymmetrical hearing loss is not characteristic of noise induced hearing loss.
In answer to a question about noise levels of the deadman whistle, the employer representative advised that she was not aware of any noise testing done on the noise level of the whistle. The employer representative was not aware of any noise testing done in the cabin.
Analysis
The issue in this appeal is whether or not the worker's claim for NIHL is acceptable. There are two ways in which a worker may sustain compensable NIHL as a result of an accident at work. The first is an acute acoustic trauma. This involves an instantaneous NIHL resulting from a single exposure at close range. The other way a worker may sustain compensable NIHL is by long-term exposure to noxious levels of occupational noise.
In this appeal there is no evidence of an acute acoustic trauma, as a result the panel must decide whether the worker has an acceptable claim for NIHL caused by long term exposure to occupational noise. In order for the worker’s appeal to be successful, the panel must find that during the course of his employment with the accident employer, the worker sustained NIHL due to exposure to the levels of noxious noise as set out in the policy. On a balance of probabilities, the panel finds that the evidence does not establish that the worker suffered a NIHL caused by long-term workplace noise exposure, and accordingly his claim is not acceptable.
In reaching this decision, the panel notes that the worker's hearing loss is asymmetrical; it is significantly worse in his left ear than his right. While it is possible for a worker to sustain a one- sided NIHL claim, the facts in this case do not support a finding that the noise exposure to the left ear was significantly different from the noise exposure to the right ear. The worker submitted that the cause of the left ear hearing loss was noise caused by the operation of a warning device (air whistle) nearer his left ear than his right and the location of a radio nearer to his left ear. The panel considered this argument, but is unable to find that the worker's left ear is exposed to significantly greater noise than his right ear. The panel considered the layout of the cabin, including the location of the whistle and radio, but cannot attribute the significantly increased exposure that would be necessary for the asymmetrical hearing loss to this factor.
The panel notes that it is unusual in cumulative NIHL cases for there to be such a significant difference between the hearing loss in the worker's ears. The progression of the loss in the left ear versus right ear cannot be explained by the noise exposure in the workplace.
The panel attaches significant weight to the opinion of the WCB ENT consultant who reviewed the hearing tests and concluded that:
"The audiogram of 1995 shows normal hearing in both ears. The subsequent audiograms show progressive sensorineural hearing loss in the left ear only. The hearing in the right ear remains normal till the last audiogram dated 2012. This is a progressive unilateral sensorineural hearing loss. Occupational NIHL is usually bilateral and symmetrical. MRI rules out the possibility of acoustic neroma."
The panel notes that the worker's representative relied upon the evidence of an audiologist and a specialist in Rhinology and Endoscopic Sinus Surgery. The panel is unable to attach weight to these opinions because they are based on the worker's description of his duties and noise in his workplace, specifically that his left ear sustained greater exposure to noise than his right ear. As noted above, the panel does not accept that the noise exposure in the cabin was significantly greater for the worker's left ear than his right ear. The panel finds this is not consistent with the evidence.
Finally, the panel notes that the policy provides that the worker must have been exposed to noxious 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. The evidence does not establish that this noise threshold was met.
The panel is unable to find, on a balance of probabilities, that the worker sustained a NIHL as a result of his job duties with the employer.
The worker's appeal is dismissed.
Panel Members
A. Scramstad, Presiding OfficerA. Finkel, Commissioner
P. Walker, Commissioner
Recording Secretary, B. Kosc
A. Scramstad - Presiding Officer
Signed at Winnipeg this 1st day of May, 2015