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. 2017 May;38(2):212–222. doi: 10.1055/s-0037-1601576

A Hearing Loss Prevention Outreach Program for Farmers and Motorsports Enthusiasts

Melanie Buhr-Lawler 1,✉
PMCID: PMC5435472  PMID: 28522895

Abstract

Many farmers and motorsports enthusiasts in rural areas attend tractor pulls, which are loud motorsport competitions using tractors and trucks with powerful, modified engines. The high noise levels experienced by farmers and motorsports fans in their recreational and occupational activities are not addressed by traditional hearing conservation programs. The University of Wisconsin–Madison audiology group has established an annual hearing loss prevention outreach project at the Dairyland Super National Truck and Tractor Pull in Tomah, Wisconsin. The objectives of the outreach are to provide hearing protection to those at the tractor pull, to document tractor pull noise levels, and to encourage tractor pull attendees to use hearing protection at work and in their other recreational activities. This study establishes that hearing loss prevention outreach at tractor pulls is necessary due to the high noise levels during the competitions. The number of earplugs distributed and the percentage of individuals who accept them indicates that this outreach is effective in the short term. It is yet to be determined if this type of hearing loss prevention project can create long-term shifts in cultural attitudes about rural noise and lead to increased hearing protection usage in the occupational and recreational lives of tractor pull attendees.

Keywords: Hearing loss prevention, hearing conservation, recreational noise exposure, sound level measures, audiology outreach, rural noise, farm noise, tractor pull, motorsports, earplugs, hearing protection

Learning Outcomes: As a result of this activity, the participant will be able to determine if rural hearing loss prevention outreach at a tractor pull is warranted and effective.

A tractor pull is a motorsport event wherein trucks and tractors compete to determine the machine that can pull a heavy weight the longest distance on a track. The trucks and tractors that compete in pulls have modified engines, and in many cases, multiple engines (Fig. 1). Tractor pulls have been described as the world's heaviest and most powerful motorsport by event organizers and enthusiasts.1 There are different classes of tractors in the competitions, depending on the machine type and its weight. The trucks and tractors contain modified engines that may include jet and aircraft engines as well as military machinery and drag racing components.1

Figure 1.

Figure 1

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A farm tractor competes at the 2011 Dairyland Super National Truck and Tractor Pull in Tomah, Wisconsin. LaCrosse Tribune file photo. Reprinted with permission of La Crosse Tribune, La Crosse, Wisconsin.

Due to the large, powerful engines used in the competitions, tractor pulls are anecdotally understood to be extraordinarily loud events. The National Institutes of Health (NIH) Noisy Planet Web site briefly mentions tractor pull noise in their Monster Noise Levels at Monster Truck Rallies publication.2 In the Morley et al research cited by the NIH, however, only motocross and monster truck rally noise levels were surveyed. At motocross and monster truck events, the peak slow-rate sound levels were 120 decibels, A-weighted sound level (dBA) in the crowd and 125 dBA for employees.2 3 High noise levels at other motorsports, such as car racing, motorcycle racing, and monster truck rallies,4 5 6 have been documented; however, no formal studies have been published on noise levels at tractor pull competitions.

The Budweiser Dairyland Super National Truck and Tractor Pull was established in 1976 and is attended by ∼60,000 fans annually.7 The event is commonly known as the Tomah Tractor Pull, because of its location in Tomah, Wisconsin. Tomah is a town of ∼9,300 residents in central Wisconsin, surrounded by rural farmland. Approximately 5.7 million people live in the state of Wisconsin, with ∼1.5 million of those individuals residing in rural areas of the state.8 9 The 2013 National Tractor Pull Association (NTPA) Tomah Tractor Pull Demographic Survey found that the most common occupation for tractor pull attendees was agriculture/forestry (29.1% of respondents). The survey also found that attendees of the Tomah Tractor Pull are predominately male (76.8%), with the largest group of attendees being between ages 35 and 59 years (52.9%).10

According to the most recent agricultural census conducted by the United States Department of Agriculture in 2012, there are 69,754 farms in the state of Wisconsin.11 Workers on these farms who make up the largest demographic group at the Tomah Tractor Pull are at risk for occupational hearing loss due to their noisy profession. Farm equipment, such as tractors and combine harvesters without cabs, can reach levels ≥ 90 to 100 dBA.12 13 14 15 Newer, modern tractors with enclosed cabins for the driver can lower daily noise exposure to safe levels.16 However, many farmers do not remain inside tractor cabs the entire work day. Other noisy equipment is also frequently utilized on farms, such as grain dryers and chainsaws, which can reach levels of 110 dBA.17 Farm animals also can create high noise environments for farmers; for example, pig squeals are documented to reach 100 dBA.14 As a result of their noisy profession, farmers have a higher percentage of sensorineural hearing loss than the general population.18 19 20

Most workers who are exposed to high noise levels, such as factory employees, are regulated by the Occupational Safety and Health Administration (OSHA). OSHA's regulations limit noise exposure and recommend or mandate hearing protection to prevent occupational noise-induced hearing loss. Specifically, OSHA requires that employers administer a hearing conservation program when employees are exposed to ≥85-dBA time-weighted average over an 8-hour work day.21 This is referred to by OSHA as the action level. OSHA designates a 90-dBA time-weighted average over an 8-hour day as the permissible exposure limit, or PEL. OSHA regulates that workers cannot be exposed to levels at or above this PEL due to risks for noise-induced hearing loss.21 The National Institute for Occupational Safety and Health has standards that are more protective than the OSHA standards.22 For the purposes of benchmarking noise levels in this study, however, OSHA guidelines will be used, as OSHA's regulations are the current legal requirements in the United States.

Workers on farms that employ 10 or fewer employees are exempt from traditional OSHA regulated hearing conservation programs under the Appropriations Act.23 Although many farms are high-noise environments, small-scale farmers must implement their own hearing conservation program to protect themselves and their employees from occupational hearing loss.

In addition to their occupational noise exposure, many Tomah Tractor Pull attendees are exposed to noise in their recreational hobbies. According to the 2013 NTPA Tomah Tractor Pull Demographic Survey, 38.9% of tractor pull attendees reported their hobbies include hunting, 24.4% reported NASCAR, 23.4% reported tractor restoration, and 23.3% reported snowmobiling.10 (p.15) Further, the NTPA survey found that 81.4% of the attendees had attended the Tomah Tractor Pull for 2 or more years, with 25.8% of the survey participants attended for 16 or more years.11 The high noise levels in tractor pull attendees' hobbies, in conjunction with common occupational noise exposure, place them at high risk for noise-induced hearing loss.

Farmers' perceptions and attitudes pose potential challenges to hearing loss prevention outreach. Some farmers may not be well informed about the effects of noise exposure because of the OSHA exemption from hearing conservation program enrollment. Among farmers who are aware of the risk of permanent hearing loss, some believe that hearing loss is unavoidable.24 Further, many farmers who are aware of the potential for noise-induced hearing loss and the importance of hearing protection remain unlikely to regularly use hearing protection at work or in recreation.25 Farmers commonly report the use of hearing protection interferes with communication with others while working.24 Gates and Jones suggest that creating habits of regular hearing protection usage, increasing accessibility of hearing protection, raising awareness of high noise levels, and creating positive relationships with the farming community may increase the use of hearing protection by farmers.25

Rationale

The purposes of this informal study were to better understand the needs of a rural population underserved by traditional hearing conservation programs, and to determine how university outreach programs might benefit the people at an annual rural tractor pull event.

Methods

This study was conducted as part of a hearing loss prevention outreach project at the Tomah Tractor Pull. Data were collected over three successive tractor pulls (2014 to 2016). The study consists of three components: an observation of the number of earplugs provided each year; cross-sectional recordings of sound levels during tractor pull events; and informal, qualitative discussions about attitudes toward hearing loss prevention.

Outreach Project Overview

The University of Wisconsin–Madison Audiology Hearing Loss Prevention Outreach Project was inspired by the department's long-standing commitment to audiology outreach, hearing loss prevention, and an enduring University of Wisconsin–Madison concept, known as the Wisconsin Idea. In brief, the Wisconsin Idea is a concept that the University's mission should extend beyond the classroom into the community and the state. Approximately three audiologists and five Au.D. students comprised each outreach group. The outreach took place over 2 consecutive days at the 4-day Tomah Tractor Pull each year.

There were three objectives to the outreach: (1) to provide people at the Tomah Tractor Pull with the means to protect themselves from the immediate risk of permanent, noise-induced hearing loss via earplugs; (2) to implement an effective educational program that encourages carryover of hearing protection into participants' personal and professional lives in a sustainable way; and (3) to provide University of Wisconsin–Madison Au.D. students with the opportunity to experience the benefits of direct community engagement in their future profession. Data collection stemmed from the first two outreach objectives as well as the desire to document tractor pull noise levels.

Hearing Protection Provided

Free disposable earplugs were distributed by the outreach group throughout the entire tractor pull grounds, which included the puller area, vendor areas, midway, audience areas, and pit. The group walked throughout the grounds in University of Wisconsin–Madison attire carrying signage identifying them and the free earplugs. The group also was stationed in the annual Kids Club event to distribute earplugs to the numerous children doing activities, eating, and meeting tractor pullers. All the earplugs were labeled prior to the event with a positive message to promote healthy hearing habits. The labels read: “Bucky Badger wants YOU to protect your hearing. The sound of a tractor pull can reach 110 decibels and can cause permanent hearing loss if no hearing protection is used. Protect your hearing while you enjoy the Tomah Tractor Pull. It's never too late to keep your ears safe.” In 2015 and 2016, the outreach group had a booth in the midway where people could obtain earplugs. The booth had a custom-made poster promoting healthy hearing, as shown in Fig. 2. Each year, the outreach group tracked the number of earplugs distributed. In 2016, the group members estimated that the majority of individuals took earplugs when they were offered to them.

Figure 2.

Figure 2

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University of Wisconsin–Madison Au.D. student Ariel Young by the 2015 audiology booth at the Tomah Tractor Pull. Photo taken by the author and used with permission.

Sound Level Measurements

The hearing loss prevention outreach project piloted at the Tomah Tractor Pull in 2014, and informal sound level measures were conducted in the grandstand area via an iPad (Apple Inc., Cupertino, CA) sound level measurement application Decibel 10th Professional Noise Meter (SkyPaw Co. Ltd, Hanoi, Vietnam).

In 2015, sound levels were measured using a 3M (St. Paul, MN) sound level meter, as shown in Fig. 3, in the front viewing area of the tractor pull grounds. In 2016, sound level measurements were conducted using a 3M sound level meter using slow-response dBA weighting at various locations on the tractor pull grounds. These sound level measurements were conducted in the following locations: (1) the pit area, where the machines await competition; (2) the area of the grounds where the tractors are kept, cared for, and warmed up by the pullers (the puller area); (3) the midway during a chainsaw art demonstration; and (4) the tractor pull audience area, both in the front viewing area and in the grandstands in the second row from the top. An aerial view of these sound level measurement locations is shown in Fig. 4. Sound level measurements were taken from the grandstand location because it is the furthest seating from the competing machines and a popular location for attendees to view the event. The grandstand location is estimated to be 125 to 200 feet at the closest point from the machines competing on the tractor pull tracks. Ambient sound levels were measured between pulls, when no machines were competing, but other tractors were running and announcements were being made. Sound levels also were measured during individual pulls.

Figure 3.

Figure 3

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Sound level measurement at the 2015 tractor pull. Photo credit: Mark Hoffman for the Milwaukee Journal Sentinel. Reprinted with permission of Mark Hoffman for the Milwaukee Journal Sentinel, Milwaukee, WI.

Figure 4.

Figure 4

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Sound level measurement locations on the Tomah Tractor Pull grounds. Image taken on June 20, 2014. Photo credit to Allan Roof of Tomah Air Photos. Reprinted with permission of Allan Roof of Tomah Air Photos, Tomah, WI.

All 2016 sound level measurements were taken on June 24, 2016, prior to and during the 11:00 am pull that included the Light Unlimited, Super Stock Diesel 4×4s, Super Farm Tractors, and Mini-Rods machines. Multiple sound level measurements were taken in all conditions, with the exception of the chainsaw art demonstration. The number of samples taken in each condition varied based on factors such as number and duration of pulls as well as access to locations. For example, the outreach member conducting the sound level measurements was only allowed to remain in the pit area for a few minutes prior to the competition due to safety regulations.

Results

Hearing Protection Provided

In 2014, all 2,000 pairs of earplugs brought to the Tomah Tractor Pull were distributed over the course of 2 days. In 2015, 3,700 of the 4,000 pairs of earplugs brought were distributed. In 2016, all 3,000 pairs of earplugs that were brought were distributed. The variability in the number of earplugs available was due to funding differences from year to year.

From the 2016 group's estimates, 80% of adults who were offered earplugs took them. This percentage was judged to be higher than that in preceding years. Most (∼90%) of those who received earplugs were approached by an outreach group member; ∼10% of earplug recipients requested them without being approached. One hundred percent of the families in the Kids Club took earplugs for their children in 2016. These estimates do not include individuals who brought their own earplugs or earmuffs to the event.

Sound Level Measurements

In 2014, the peak sound level measured in the grandstands during the Light Unlimited tractor division was 110 dBA. In 2015, the peak sound level in the light tractor division was 128 dBA in the front viewing area. No formal measurements were made during other tractor divisions or in other locations in 2014 or 2015.

A larger sample of sound level measurements at the various locations cited previously was obtained in 2016. These results are shown in Fig. 5. In the pit area, the average ambient noise level was 68.5 dBA, and peak ambient noise level was 70 dBA. These measurements were taken 40 minutes prior to a tractor pull competition. In the puller area, the average ambient noise level was 59 dBA, and the peak ambient noise level was 61 dBA. These measurements were taken 30 minutes prior to a competition. In the puller area during motor warm-up, the average sound level was 103.8 dBA, and the peak sound level was 112 dBA. A single sound level measure taken during a chainsaw competition in the midway was 88.4 dBA at approximately 7 feet from the chainsaw artist.

Figure 5.

Figure 5

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Peak and average sound levels (dBA) at the 2016 Tomah Tractor Pull at various locations and with different noise types. Abbrevation: dBA, decibels, A-weighted sound level.

In the front viewing area, the average ambient noise level was 80.9 dBA, and the peak ambient noise level was 87 dBA. During pulls, the average sound level in the front viewing area was 108.6 dBA, and the peak sound level was 125 dBA. In the grandstands, the average ambient noise level was 82.9 dBA, and the peak ambient noise level was 90.3 dBA. During pulls, the average sound level in the grandstand was 99.7 dBA, and the peak sound level was 122.2 dBA.

Attitudes toward Hearing Protection

Each year, the University of Wisconsin–Madison outreach group received many comments and participated in many conversations with tractor pull attendees, participants, and workers about the high noise levels at the event and attitudes toward hearing protection. No formal survey of attitudes was conducted; however, samples of those comments and conversations were recorded in writing. For example, in 2014, one worker stated that the large motor pulls were so loud that he could “feel the ground shake.” In 2016, comments included several supportive statements, such as thank you for the earplugs and services; requests for earplugs for themselves and their families; requests for assistance with proper earplugs insertion; and a warm welcome and gratitude for the groups' presence from tractor pull organizers.

The group also received comments that reflected a less positive attitude toward hearing loss prevention. Examples included: “Earplugs are for sissies,” “I like it loud,” and frequently, “I'm deaf already.” As this was an outreach effort, the University of Wisconsin–Madison audiology group attempted to engage these individuals in friendly, positive conversation to strongly encourage the use of hearing protection to prevent further hearing loss. It was noted each year that if one member of a group of attendees took earplugs, particularly a crowd of all males, it was much more likely that the other group members would then accept earplugs as well. Several individuals who initially refused earplugs later requested earplugs once the tractor pull competition had started and noise levels increased.

Discussion

The University of Wisconsin–Madison Audiology Hearing Loss Prevention Outreach Project was successful in reaching its most basic goal, which was to provide Tomah Tractor Pull attendees, pullers, and workers the immediate means to protect their hearing at the event. The number of earplugs distributed (8,700 total pairs over 3 years) approximates the number of people reached by this hearing loss prevention project to date. Due to the fast-paced, conversation-based earplug distribution at roving locations on tractor pull grounds, no formal data have been collected yet on the exact percentage of individuals approached who took and used the earplugs. Informal estimates indicate that the majority of adults and all of the families of children who were offered earplugs took them, and this percentage was higher in 2016 than in previous years. No data are available on the number of individuals who used the earplugs during the event, although the outreach group observed that the majority of earplug recipients wore them. One Au.D. student observed that the grandstand area looked like “a sea of orange earplugs” during the 2016 pull.

In 2016 and 2014, 100% of the available earplugs were distributed, and it is likely that more earplugs would have been distributed had more been available. In 2015, a rainstorm caused the group distributing the earplugs to leave early with 300 pairs of earplugs undistributed. The number of individuals who brought their own hearing protection appeared to be higher in 2016 than in 2014 and 2015 upon informal observation.

One limitation of this project is the availability of a consistent funding source for the earplugs. Another limitation is the costs associated with travel and overnight stay. The grant money that has supported the outreach has only been able to provide for outreach at the first 2 of the 4 days of the pull. Although many attendees return for multiple days of the pull and could theoretically reuse their earplugs day after day, new attendees arrive for the later days of the pull. Therefore, it is likely that there are many tractor pull spectators without hearing protection, particularly on the 2 days that the outreach group was not present. No control data are available regarding hearing protection at Tomah Tractor Pull for years prior to 2014; therefore, it is not possible to compare earplug usage from the outreach to previous years.

Tractor pulls are, by all informal accounts, very loud. This project allowed for preliminary measurement and documentation of noise levels at this popular rural motorsport. The peak noise levels measured at the Tomah Tractor Pull are consistent with those obtained at monster truck and motocross events.4 The sound level measures obtained at the Tomah Tractor Pull were taken during weekday events of the 4-day pull; the larger (and potentially louder) engines competing later were not measured. Therefore, the peak and average noise levels reported here may under-represent the high noise levels at tractor pulls. Sound level measures were taken periodically for several hours, but no dosimetry or long-term sound level studies were made. Despite the possible underestimation of noise levels at the tractor pull, the average sound level data obtained indicate that attendees in the front viewing area exceeded OSHA's PEL for noise exposure after less than 1 hour of watching pulls. Viewers in the grandstand area exceed OSHA's PELs after watching pulls for approximately 2 hours.21 Each tractor pull show lasts 2 to 4 hours. Many (63.6%) of the attendees stay 2 or more nights at the tractor pull; it can be assumed that those who stay overnight view more than one show.10 Therefore, based on the sound levels measured at the pull and the OSHA standards for noise exposure, most attendees are at risk for noise-induced sensorineural hearing loss from viewing the tractor pull if they do not use hearing protection. Further, sound level measurement across all events of the competition in future years will provide data to more accurately represent the risk that noise levels at the tractor pull pose to hearing.

Although no formal data were gathered on attitudes, the University of Wisconsin–Madison Audiology Outreach Project observed that the general trend in attitude of tractor pull attendees, participants, and workers was toward increased acceptance of the use of hearing protection over the 3 years of the outreach project. The audiology outreach group noted that tractor pull fans were much more likely to take earplugs when they were offered with the question “Did you get your free earplugs?” rather than “Would you like a pair of earplugs?” This suggests that presenting hearing loss prevention as the norm, rather than an option, may increase interest and compliance in the short-term. The increased acceptance noted in 2016 also may be because the annual outreach presence at the Tomah Tractor Pull is normalizing the use of earplugs.

Future directions of this project include a more formalized measure to assess attitudes and carryover of the use of hearing protection into the noisy occupations and hobbies of the tractor pull attendees. Although one of the aims of the University of Wisconsin–Madison Audiology Hearing Loss Prevention Project at the Tomah Tractor Pull is to create long-term lifestyle shifts toward increased acceptance and use of hearing protection, it is not clear whether progress has been made toward this goal. Further research will be needed to assess the reach and long-term impact of this outreach project. The University of Wisconsin–Madison audiology group plans to continue this outreach in future years, pending funding.

Conclusions

The noise levels at the Tomah Tractor Pull place its attendees, participants, and workers at risk for permanent, noise-induced hearing loss, if they do not properly use hearing protection at the event. A large percentage of tractor pull attendees are exposed to additional high noise levels in their occupations, such as farming. The noisy hobbies of many attendees place them at further increased risk for noise-induced hearing loss. The University of Wisconsin–Madison Hearing Loss Prevention Outreach Project has been successful in helping reduce noise exposure for some of the individuals at the Tomah Tractor Pull through the provision of free earplugs. Many attendees, participants, and workers utilize the earplugs provided, and the percentage of those who take and wear earplugs has increased over the years. Given the noise levels of the event and the apparent rise in popularity of hearing protection use by its attendees, other clinics, especially those working in underserved rural populations, are encouraged to embark on a similar program. Further investigation is necessary to determine if the cultural attitudes toward hearing loss prevention have shifted due to the outreach efforts and if the use of hearing protection carries over into the other areas of the personal and professional lives of tractor pull attendees.

Acknowledgments

The author would like to thank audiology clinical professors Amy Kroll, Amy Hartman, and Rachel Lee; visiting assistant professor Sara Misurelli; University of Wisconsin–Madison Au.D. students who participated in the outreach; Shae Fox and the Tomah Tractor Pull organizers. The author would also like to thank University of Wisconsin–Madison Relations and the Wisconsin Idea Outreach Grants, and the Ira and Ineva Reilly Baldwin Wisconsin Idea Mini-Endowment, and the University of Wisconsin–Madison Speech and Hearing Clinic.

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