WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 1059/15

Transcription

1 WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 1059/15 BEFORE: S. Martel: Vice-Chair HEARING: May 21, 2015 at Toronto Written DATE OF DECISION: June 3, 2015 NEUTRAL CITATION: 2015 ONWSIAT 1205 DECISION UNDER APPEAL: WSIB Appeals Resolution Officer (ARO) decision, dated March 17, 2014 APPEARANCES: For the worker: For the employer: Interpreter: A. LaDouceur, Union representative Not participating N/A Workplace Safety and Insurance Appeals Tribunal Tribunal d appel de la sécurité professionnelle et de l assurance contre les accidents du travail 505 University Avenue 7 th Floor 505, avenue University, 7 e étage Toronto ON M5G 2P2 Toronto ON M5G 2P2

2 Decision No. 1059/15 REASONS (i) Introduction [1] The worker appeals a decision of the ARO, which denied entitlement for Noise-Induced Hearing Loss (NIHL) because the worker did not meet the minimum threshold of 22.5dB of hearing loss in each ear. [2] The hearing proceeded in writing in accordance with the Tribunal s Practice Direction on Written Appeals. Mr. LaDouceur provided written submissions to the Tribunal on March 12, (ii) Issue [3] The issue under appeal is the worker s entitlement to occupational NIHL. (iii) Background [4] The worker was born in He worked as a crane operator for a steel company from 1965 to 1993, when he was laid off. He then retired in His last day of work was in February There is no dispute that the worker did not have occupational noise exposure beyond [5] The worker first filed a claim for NIHL in 1984 but at that time his claim was denied because he had insufficient hearing loss. The worker submitted additional audiograms in 1992 and 1995, which he submits show sufficient hearing loss to qualify for NIHL. The Board again denied his claim. The worker appealed this denial in The Board obtained information from the employer in 2008, which showed that the worker would have been exposed to noise levels ranging from 76 to 88 db(a) from 1964 to 1971 and from 88 to 96 db(a) from 1971 to Based on these figures, the Board calculated that the worker met the minimum exposure levels found in its policy. The Board held, however, that the 1992 and 1995 audiograms failed to show sufficient hearing loss. [6] The worker now appeals the denial of NIHL. One of the issues on appeal is whether the bone conduction (BC) or air conduction (AC) measurements should be used. [7] There are two measurements used when measuring hearing loss: AC or BC. The Tribunal discussion paper on hearing loss and tinnitus ( Hearing Loss and Tinnitus, Dr. John Rutka, MD, FRCSC, February 2003, Revised July 2013) describes the pure tone audiogram as follows: An individual's threshold hearing to pure tones at different frequencies ( Hz) is performed. Air conduction (AC) thresholds are delivered via headphones and the individual is asked to respond to the sound of the lowest intensity (in db) they hear at the frequency being tested. When a conductive hearing loss is suspected the ear canal and inner ear mechanisms for transmission of sound energy to the inner ear are bypassed by placing a bone vibrator over the mastoid which directly stimulates the inner ear. Bone conduction (BC) thresholds are obtained in this fashion. In complex situations (mixed hearing losses) it may also be necessary to mask the ear not being tested (to prevent crossover of sound to the other ear).

3 Page: 2 Decision No. 1059/15 In a pure sensorineural hearing loss, AC thresholds should be the same as BC thresholds. In a pure conductive hearing loss BC thresholds will be better than AC thresholds. In a mixed hearing loss, elements of both sensorineural and conductive hearing loss are present. When AC thresholds are better than BC thresholds in a tested ear this usually implies an exaggerated hearing loss is present. [8] The Board audiologist used the BC thresholds in the left ear where these differed from the AC thresholds. Mr. LaDouceur submits that the AC thresholds are the only ones that should be used in this case because Dr. O Neill, an otolaryngologist, diagnosed the worker with a bilateral nerve loss consistent with noise exposure and there is no suggestion that there is any conductive component to the worker s hearing loss. (iv) Law and policy [9] While the worker first filed his NIHL claim in 1984, there is no dispute that he did not have sufficient hearing loss at that time to qualify for benefits. Accordingly, I have considered this claim under the pre-1997 Workers Compensation Act for accidents that arise between 1990 and [10] Operational Policy Manual (OPM) Document No , Noise-Induced Hearing Loss, On/After January 2, applies to this appeal because the issue concerns the audiograms of 1992 and 1995 and whether they demonstrate sufficient hearing loss to qualify for NIHL entitlement. [11] OPM Document No sets out the test for initial entitlement in cases of hearing loss and states, in part: Guidelines Description of the condition Noise-induced hearing loss (NIHL) is a permanent loss of hearing in both ears resulting from sensorineural (inner ear) damage due to prolonged, continuous, hazardous noise exposure. Entitlement Workers with occupational NIHL that is sufficient to cause a hearing impairment may be entitled to benefits. Entitlement to health care and rehabilitation benefits begins with a hearing loss of 22.5 db in each ear when the hearing loss in the 4 speech frequencies (500, 1000, 2000, and 3000 Hertz) are averaged. The following is persuasive evidence of work-relatedness in claims for sensorineural hearing loss continuous exposure to 90 db(a) of noise for 8 hours per day, for a minimum of 5 years, or the equivalent, and a pattern of hearing loss consistent with noise-induced sensorineural hearing loss. A presbycusis (aging) factor of 0.5 db is deducted from the measured hearing loss (averaged over the 500, 1000, 2000, and 3000 Hz frequencies) for every year the worker 1 The Board in this case mistakenly advised that OPM Document No Occupational Noise-Induced Hearing Loss for accidents before January 2, 1990 applied to this appeal. The ARO decision on appeal, however, and Mr. LaDouceur s submissions, correctly rely on OPM Document No and this is the policy that I have relied upon. Given that Mr. LaDouceur s submissions rely on OPM Document No , I have not deemed it necessary to ask him for further submissions regarding the applicable policy because I am applying the policy he relies upon.

4 Page: 3 Decision No. 1059/15 is over the age of 60 at the time of the audiogram. The hearing loss that remains after the presbycusis adjustment is then used to determine entitlement to benefits. Entitlement to health care and rehabilitation benefits is available when the adjusted hearing loss is at least 22.5 db in each ear.... Permanent impairment Permanent impairment from sensorineural hearing loss is determined using the rating schedule prescribed in section 18(1), O. Reg 175/98. This rating schedule is the American Medical Association Guides to the Evaluation of Permanent Impairment, 3rd edition (revised) (AMA Guides). Those claimants whose hearing loss is sufficient to result in a permanent impairment benefit as recognized by the AMA Guides (at or above 26.25/26.25 db or 25/32.5 db in the better/worse ear, respectively) are referred for a Non-Economic Loss (NEL) determination. Average hearing losses are never rounded for permanent impairment calculations using the AMA Guides. Exceptions Since individual susceptibility to noise varies, if the evidence of noise exposure does not meet the above exposure criteria, claims will be adjudicated on the real merits and justice of the case, having regard to the nature of the occupation, the extent of the exposure, and any other factors peculiar to the individual case. [12] The policy is silent regarding the use of AC or BC thresholds when calculating hearing loss. (v) Analysis [13] In this case, the Board ultimately accepted that the worker met the minimum noise exposure requirements. Information provided by the employer shows that the worker was exposed to up to 94 db(a) over the course of 22 years. I am satisfied that he meets the policy s requirement of continuous exposure to at least 90 db(a) of noise for eight hours per day, for a minimum of five years. [14] The Board also accepted that the hearing loss was consistent with noise-induced hearing loss with notching in the 4000 Hz area of the audiograms. The claim was denied, however, because the Board concluded that the noise-induced hearing loss did not meet the minimum threshold of 22.5 db in each ear required for entitlement under OPM Document No [15] The issue on appeal concerns the measurements the Board used in calculating the average hearing loss in the four speech thresholds. [16] There are two relevant audiograms, dated 1992 and The 1992 audiogram was done shortly before the worker last worked and the 1995 audiogram was done about 2 ½ years after he stopped working. The worker was 60 years old at the time of the 1992 audiogram and 63 years old at the time of the 1995 audiogram. [17] The Board audiologist reviewed the 1992 and 1995 audiograms and provided the following calculations:

5 Page: 4 Decision No. 1059/15 November 9, 1992 Loss of Hearing (decibels) Audiogram at Hz Right Ear Left Ear 500 Hz (BC) 1000 Hz Hz Hz (BC) Average 130/4= /4=21.25 Presbycusis factor 0 0 Adjusted September 19, 1995 Loss of Hearing (decibels) Audiogram at Hz Right Ear Left Ear 500 Hz (BC) 1000 Hz Hz Hz Average 135/4= /4=22.50 Presbycusis factor Adjusted [18] The audiologist appears to have taken BC measurements rather than AC measurements for the left ear at 500 Hz and 3000 Hz in the 1992 audiogram and the BC measurement rather than air conduction measurement at 500 Hz in the 1995 audiogram. At other frequencies, the AC and BC measurements were the same. The explanation the audiologist provided for such was as follows: Noise induced hearing loss is typically a symmetrical hearing loss that is completely sensory neural in nature. Bone conduction measures the cochlear function. Occupational noise damage affects the cochlea and not the outer or middle ear structures. The professional standard in Ontario for manual pure-tone Audiometry is to include air and bone conduction and masking when necessary.

6 Page: 5 Decision No. 1059/15 The worker has no conduction hearing loss and bone conduction is used to obtain the response of the cochlea. [19] Mr. LaDouceur relies on the Tribunal discussion paper regarding BC and AC thresholds, which states: The pure tone audiogram forms the basis for assessing if an individual qualifies for Workplace Safety and Insurance Board (WSIB) benefits in the Province of Ontario. A weighted pure tone average from frequencies at 500, 1000, 2000 and 3000 Hz is required for this determination from AC thresholds if a pure sensorineural hearing loss is present or from BC thresholds if any conductive element to hearing loss is present. [Emphasis added] [20] Mr. LaDouceur submits that in this case, the worker does not have a conductive element to his hearing loss and that accordingly, the AC testing results should be used. If the AC testing results are used, he submits that the 1992 audiogram meets the minimum threshold. [21] Using AC results only, the following calculations would apply: November 9, 1992 Loss of Hearing (decibels) Audiogram at Hz Right Ear Left Ear 500 Hz Hz Hz Hz Average 130/4= /4=25 Presbycusis factor 0 0 Adjusted hearing loss September 19, 1995 Loss of Hearing (decibels) Audiogram at Hz Right Ear Left Ear 500 Hz Hz Hz Hz Average 135/4= /4=23.75 Presbycusis factor Adjusted

7 Page: 6 Decision No. 1059/15 [22] I note that the worker meets the minimum threshold using the 1992 audiogram but not the 1995 audiogram, although the figure of in the left ear is just shy of the minimum qualification for health care benefits. In any event, I prefer the 1992 audiogram because it was done about four months before the worker stopped working and therefore best represents his occupational hearing loss. [23] I also agree with Mr. LaDouceur s submissions that AC thresholds can be used in this worker s case as there is no suggestion in any of the medical reports that there is a conductive element to his hearing loss. Furthermore, the differences between the AC and BC thresholds are not very significant, which suggests that the AC thresholds are an accurate measurement of the worker s sensorineural hearing loss. I note that a similar approach was recently followed in Decision No. 566/14 (June 9, 2014), which relied on the Tribunal discussion paper prepared by Dr. Rutka and found that AC measurements could be used in a pure sensorineural hearing loss. Alternatively, I would rely on subsections 4(4) of the pre-1997 Workers Compensation Act and 124(2) of the Workplace Safety and Insurance Act, which state that in determining a claim for benefits, if it is not practicable to determine an issue because the evidence for or against it is approximately equal in weight, the issue shall be resolved in favour of the claimant. I therefore rely on the 1992 audiogram, which shows a hearing loss of 32.5 db in the right ear and 25.0 db in the left ear, using AC measurements. [24] I find the worker s hearing loss in 1992 meets the Board policy requirement of at least 22.5 db hearing loss in each ear. [25] Accordingly, the appeal is allowed.

8 Page: 7 Decision No. 1059/15 DISPOSITION [26] The appeal is allowed. The worker has sufficient hearing loss in each ear to satisfy the threshold of hearing loss in OPM Document No DATED: June 3, 2015 SIGNED: S. Martel