Every abrasive blaster that NIOSH monitored at a Louisiana shipbuilder in 2024 had a full-shift noise exposure above 100 dBA, with readings of 100.0 to 108.1 dBA under OSHA criteria, against a permissible limit of 90 dBA (NIOSH Health Hazard Evaluation Report 2023-0084-3425, 2025). Under OSHA’s own exposure table, 100 dBA is acceptable for only 2 hours a day. The damage shows up later in audiograms: 80.5% of 5,539 welding, sanding and cutting workers at a Shanghai shipyard had a hearing threshold above 25 dB HL (Jiang et al., JAMA Network Open 2021), and subcontracted workers at Turkish shipyards had nearly double the hearing-loss rate of permanent staff. Shipyards sit between heavy fabrication and construction, and this page takes the vessel-specific angle that our construction worker hearing loss statistics do not cover. We aggregated data from NIOSH, OSHA, the Bureau of Labor Statistics, the National Shipbuilding Research Program (NSRP), the EU noise directive, and peer-reviewed dosimetry and audiometry studies from the US, Korea, China, Turkey, Indonesia and Europe.
TL;DR
- Abrasive blasting runs at 105 to 112 dBA and needle gunning at 113 dBA, among the loudest shipyard tasks (OSHA Shipyard Employment eTool).
- All four abrasive blasters monitored by NIOSH exceeded 100 dBA over a full shift (NIOSH HHE Report 2023-0084-3425, 2025).
- 13 of 30 full-shift samples (43%) at four US shipyards exceeded OSHA’s 90 dBA limit, and 22 of 30 (73%) passed the 85 dBA hearing conservation trigger (NSRP Noise Control Methods for Shipbuilding 2012).
- 629 of 1,575 Korean shipbuilding noise samples (39.9%) exceeded the limit under the OSHA calculation method (Shin et al., IJERPH 2021).
- 80.5% of 5,539 Shanghai shipyard workers had a threshold above 25 dB HL (Jiang et al., JAMA Network Open 2021).
- Hearing at 12.5 kHz worsened by 2.70 dB per year in young shipyard workers followed for four years (Jiang et al., JAMA Network Open 2021).
- 15.3% of male shipyard workers developed new speech-frequency hearing loss over a mean 5.34 years of follow-up (Yu et al., Communications Medicine 2026).
- 42% of subcontracted vs 21.88% of permanent Turkish shipyard workers had noise-related hearing loss (Azkeskin and Arikan Ozturk, 2019).
- Ship recycling torch cutters reached 94.1 to 96.4 dB(A) daily exposure with peaks up to 144.0 dB(C) (Kurt et al., Ocean Engineering 2017).
- Ship building and repairing recorded 4.8 injury and illness cases per 100 full-time workers in 2024, vs 2.7 in manufacturing (BLS SOII 2024).
1. Task Noise: Blasting, Needle Guns, Grinding and Arc Gouging
Shipyard noise is driven by a handful of surface-preparation and hot-work tasks, and the spread between them is wide. Needle gunning (a pneumatic tool that hammers rust and paint off steel with a bundle of steel rods) reaches 113 dBA, and carbon arcing or arc gouging (cutting a groove in metal with an electric arc and a jet of compressed air) spans 102 to 118 dBA (OSHA Shipyard Employment eTool). Each 5 dB step halves the permitted time under OSHA rules, so a task at 115 dBA is allowed for a quarter hour or less per day (OSHA 29 CFR 1910.95, Table G-16).
The hull itself makes it worse. Blasting inside a steel hull is enclosed, reverberant work: NIOSH measured 110.7 to 111.2 dBA there, while welding ranged from 80.4 to 111.3 dBA depending on process and distance (NIOSH HHE Report 2023-0084-3425, 2025). The question is not whether the loudest tasks exceed the limit, it is how many minutes of them a worker can absorb before the daily dose is spent.
| Metric | Value | Source |
|---|---|---|
| Abrasive blasting, typical sound level | 105 to 112 dBA | OSHA Shipyard Employment eTool |
| Needle gunning, typical sound level | 113 dBA | OSHA Shipyard Employment eTool |
| Carbon arcing and arc gouging, typical sound level | 102 to 118 dBA | OSHA Shipyard Employment eTool |
| Abrasive blasting measured inside a vessel hull | 110.7 to 111.2 dBA | NIOSH HHE Report 2023-0084-3425, 2025 |
| Angle grinder, measured at the new-build and repair sites | 90.1 to 103.7 dBA | NIOSH HHE Report 2023-0084-3425, 2025 |
| Median full-shift exposure for mineral grit blasting (maximum 114 dBA) | 95 dBA | US Bureau of Reclamation, Sandblasting Noise Project 2016 |
| Peak sound pressure level reachable during abrasive blasting | 128 dBA | Lindsey, Montana Tech 2016 |
Context note: the OSHA eTool figures are typical task levels, not exposures; a worker’s daily dose depends on how long the tool runs. Most recent available data for the blasting medians and peaks: US Bureau of Reclamation and Montana Tech, 2016.
2. Full-Shift Exposure by Trade in US Shipyards
Task readings show how loud a tool is; dosimetry (a small noise meter clipped near the ear and worn all shift) shows what a worker actually absorbs. NIOSH took 52 full-shift noise measurements at one Louisiana shipbuilder, 30 at its new-build site and 22 at its repair site (NIOSH HHE Report 2023-0084-3425, 2025). At the repair site, the four abrasive blasters logged 100.0 to 108.1 dBA under OSHA permissible-limit criteria and 103.1 to 110.8 dBA under NIOSH criteria. The NIOSH criteria include quieter sound in the average and use a 3 dB exchange rate (the permitted time halves for each 3 dB increase), so its numbers run higher than OSHA’s for the same shift.
Welders and fitters sit closer to the line, which makes them easier to overlook. Structural welders at the new-build site reached up to 95.7 dBA under OSHA criteria, and even a single grinding helper at the repair site logged 90.8 dBA under NIOSH criteria. The same survey found 13 personal air samples above manganese exposure guidelines, which NIOSH linked to uncontrolled welding fume, so the loudest trades often carry a second exposure at the same time.
| Metric | Value | Source |
|---|---|---|
| Structural welders, new build, full-shift range under NIOSH criteria (7 workers) | 87.9 to 102.4 dBA | NIOSH HHE Report 2023-0084-3425, 2025 |
| Fitters, new build, full-shift range under NIOSH criteria (4 workers) | 85.9 to 97.4 dBA | NIOSH HHE Report 2023-0084-3425, 2025 |
| Full-shift samples above OSHA’s 90 dBA limit at four US shipyards | 13 of 30 (43%) | NSRP Noise Control Methods for Shipbuilding 2012 |
| Full-shift samples above OSHA’s 85 dBA hearing conservation trigger | 22 of 30 (73%) | NSRP Noise Control Methods for Shipbuilding 2012 |
| Historical shipyard dosimetry samples above 85 dBA, 1986 to 2007 (range 25.6 to 119.0 dBA) | 844 of 3,277 | NSRP Noise Control Methods for Shipbuilding 2012 |
Math note: 844 of 3,277 is 25.8%, our own calculation from the counts the NSRP report gives. The NSRP shipyards were BAE Southeast Shipyards, Norfolk Naval Shipyard, Bath Iron Works and Vigor Shipyard. Most recent available data for the multi-yard sample: NSRP, 2012. For how employers track the hearing changes that follow these exposures, see our OSHA standard threshold shift statistics.
3. Korea: The Largest Shipbuilding Dosimetry Dataset
Korea’s shipbuilding sector supplies the biggest public shipyard dosimetry dataset we found. Of 1,575 workers sampled across 104 shipbuilding and vendor companies in 2016 to 2018, 629 (39.9%) exceeded the noise limit under the OSHA calculation method (Shin et al., IJERPH 2021). Unit assembly, an early stage of hull block construction, was the loudest department at 92.0 dBA.
The study’s sharpest finding is about breaks. Standard sampling skips lunch, yet lunch-break noise averaged 84.8 dBA overall, 95.9 dBA in hull painting and 100.9 dBA for “power” tasks, because nearby work continues while some crews rest. Rest periods in a shipyard are not reliably quiet periods, and leaving them out of sampling changes the exposure picture by up to a few percentage points of samples over the limit.
| Metric | Value | Source |
|---|---|---|
| Mean full-shift noise, all Korean shipbuilding samples (OSHA method, breaks excluded) | 88.3 dBA | Shin et al., IJERPH 2021 |
| Unit assembly department, mean noise (breaks excluded) | 92.0 dBA | Shin et al., IJERPH 2021 |
| Samples above the 90 dBA limit, KOSHA method, breaks excluded vs included | 597 (37.9%) vs 544 (34.5%) | Shin et al., IJERPH 2021 |
| Lunch-break noise during “power” job tasks | 100.9 dBA | Shin et al., IJERPH 2021 |
| Lunch-break noise in the hull painting department | 95.9 dBA | Shin et al., IJERPH 2021 |
| Adjusted odds of hearing loss, right ear, noise-exposed shipyard workers vs controls | 7.9 (95% CI 2.0-31.3) | Kim and Chung, JPMPH 2003 |
| Rise in average hearing threshold for each interquartile-range increase in noise (84.74 to 94.26 dBA): workers also exposed to organic solvents vs workers not exposed to solvents | 4.43 vs 2.06 dBHL | Choi and Kim, PLoS One 2014 |
Context note: Choi and Kim analysed 30,072 workers from Korea’s 2009 national occupational health surveillance across all industries, not shipyards alone, but solvent-heavy painting and fume-heavy welding are core shipyard trades. Kim and Chung studied 440 shipyard workers. Most recent available data: Kim and Chung 2003, Choi and Kim 2014 (2009 data), Shin et al. 2021 (2016 to 2018 data).
4. Hearing Loss Prevalence in Large Shipyard Cohorts
The two biggest shipyard audiometry cohorts come from China, and both show that loss is the norm, not the exception. In a Shanghai shipyard, 4,459 of 5,539 sanding, welding, metal and cutting workers (80.5%) had a hearing threshold above 25 dB HL at one or more frequencies between 0.25 and 8 kHz (Jiang et al., JAMA Network Open 2021). The median worker had only 7.5 years on the job.
The newer cohort tracks how fast the damage arrives. Across the Zhenhua and Jiangnan shipyards, 15.3% of male workers who started without speech-frequency hearing loss developed it within a mean 5.34 years (Yu et al., Communications Medicine 2026). Compare that with a pooled 28.8% hearing impairment prevalence across industrial workers worldwide (Salari et al., 2024): both shipyard cohorts sit at more than double that benchmark, though the hearing-loss definitions differ between studies.
| Metric | Value | Source |
|---|---|---|
| Shanghai shipyard workers with a threshold above 25 dB HL at any tested frequency | 4,459 of 5,539 (80.5%) | Jiang et al., JAMA Network Open 2021 |
| Annual hearing decline at 12.5 kHz, young workers followed 4 years | 2.70 dB per year | Jiang et al., JAMA Network Open 2021 |
| Total 4-year threshold change at 12.5 kHz | 10.8 dB | Jiang et al., JAMA Network Open 2021 |
| Male shipyard workers with speech-frequency hearing loss at baseline, test set | 1,119 of 1,720 (65.1%) | Yu et al., Communications Medicine 2026 |
| New speech-frequency hearing loss during follow-up: men vs women (training cohort) | 15.3% vs 9.5% | Yu et al., Communications Medicine 2026 |
| Pooled hearing impairment prevalence, industrial workers worldwide (69 studies) | 28.8% (95% CI 26.2%-31.6%) | Salari et al., Indian J Otolaryngol Head Neck Surg 2024 |
Definition note: “speech-frequency hearing loss” in Yu et al. means a pure-tone average of 25 dB or more across the frequencies that carry speech, a stricter test than “any frequency above 25 dB HL” used by Jiang et al. The two percentages are not directly comparable. The 12.5 kHz band lies above the 0.25 to 8 kHz range used for the clinical hearing-loss definition in the same study, so early damage there can be missed by routine testing.
5. Contract Labour and Hearing Protection Gaps
Averages hide who gets hurt. At three Turkish shipyards, audiometry showed noise-related hearing loss in 42% of subcontracted workers against 21.88% of permanent staff (Azkeskin and Arikan Ozturk, Marmara Congress 2019). The paper does not break results down by task, so it cannot say whether subcontractors were concentrated in the blasting and gouging work at the top of the noise table in section 1.
The Indonesian data point to behaviour as the lever. In a Surabaya ship-repair unit, 45.3% of workers never wore ear protectors and only 21.9% always did, and protector habit was the only factor significantly linked to hearing loss (p<0.001) (Sincihu et al., IJOSH 2019). Length of service was not significant (p=0.920), a pattern consistent with unprotected exposure, not years alone, driving the damage in this group.
| Metric | Value | Source |
|---|---|---|
| Audiometry reports reviewed at three Turkish shipyards (Kocaeli and Yalova) | 782 | Azkeskin and Arikan Ozturk, 2019 |
| Workers in the Turkish study with hearing loss (noise in all three yards measured above the legal limit) | 36% | Azkeskin and Arikan Ozturk, 2019 |
| Noise-related hearing loss: subcontracted vs permanent workers | 42% vs 21.88% | Azkeskin and Arikan Ozturk, 2019 |
| Indonesian ship-repair workers with sensorineural hearing loss | 52 of 64 (81.2%) | Sincihu et al., IJOSH 2019 |
| Share of those cases affecting both ears | 61.5% | Sincihu et al., IJOSH 2019 |
| Ear protector use: never vs always | 45.3% vs 21.9% | Sincihu et al., IJOSH 2019 |
| Measured locations above 85 dBA in the Surabaya yard (peak 109.7 dBA at an air compressor) | 12 of 17 | Sincihu et al., IJOSH 2019 |
Caveat: both studies are small, and neither reports adjustment for age, tenure or non-work noise. Most recent available data: Turkey 2019, Indonesia 2019 (2018 fieldwork).
6. What Hearing Protection and Engineering Controls Achieve
Earplugs alone may not close the gap for blasters and cutters. In a ship recycling yard, torch cutters logged daily exposures of 94.1 to 96.4 dB(A), and only earplugs plus earmuffs brought the estimated exposure below the EU’s 80 dB(A) lower action value (Kurt et al., Ocean Engineering 2017). OSHA’s shipyard guidance credits a second device with just 5 dB on top of the better one, and NIOSH recommends dual protection above 100 dBA, the level every blaster in its 2025 survey exceeded.
Engineering controls remove noise for everyone in the bay, not just the person wearing plugs. The NSRP study found an automated track grinder cut the operator’s full-shift dose by 11.2 dB compared with a coworker hand-grinding in the same shop, and moving blast pots and dust collectors outside a blast house cut levels by 8 dB. Real-world plug fit varies widely; our hearing protection fit testing statistics show why rated and achieved attenuation differ.
| Metric | Value | Source |
|---|---|---|
| Torch cutter daily exposure, no protection vs earplugs vs earplugs plus earmuffs (estimate) | 96.1 vs 84.6 vs 79.1 dB(A) | Kurt et al., Ocean Engineering 2017 |
| Highest peak recorded on a torch cutter | 144.0 dB(C) | Kurt et al., Ocean Engineering 2017 |
| Ship recycling workers above the EU 87 dB(A) exposure limit | 3 of 5 | Kurt et al., Ocean Engineering 2017 |
| Full-shift dose with an automated track grinder vs hand grinding, same shop and day | 11.2 dB lower | NSRP Noise Control Methods for Shipbuilding 2012 |
| Blast house with support equipment moved outside the work area | 8 dB reduction | NSRP Noise Control Methods for Shipbuilding 2012 |
| High-pressure hydroblasting: at the source vs at the operator console about 10 feet away | 106 vs 98 dBA | NSRP Noise Control Methods for Shipbuilding 2012 |
| Extra attenuation credited for earplugs plus earmuffs over the better single device | 5 dB | OSHA Shipyard Employment eTool |
Caveat: Kurt et al. monitored only five workers and estimated protected exposures from manufacturer ratings, not fit tests. Most recent available data: Kurt et al. 2017; NSRP 2012.
7. Limits, Injury Rates and the Compensation Fight
Shipyards are already one of manufacturing’s harder places to work. Ship building and repairing recorded 4.8 nonfatal injury and illness cases per 100 full-time workers in 2024, against 2.7 for manufacturing overall (BLS SOII 2024, Table 1). Those totals cover all recordable cases, not hearing loss alone, but they frame the workforce that faces the noise in sections 1 to 3.
The rules differ by jurisdiction, and the differences matter for blasters. The EU limit is 87 dB(A) after counting hearing protectors, with action values at 80 and 85 dB(A) (Directive 2003/10/EC); OSHA’s limit is 90 dBA. In the US, compensation is now contested: a September 2025 House committee letter asked GAO to review Longshore Act hearing-loss claims, citing that more than 37 percent are filed by claimants aged 70 and older (House Education and Workforce Committee letter to GAO 2025).
| Metric | Value | Source |
|---|---|---|
| Injury and illness rate per 100 full-time workers: ship building and repairing vs manufacturing vs all industries | 4.8 vs 2.7 vs 2.6 | BLS SOII 2024, Table 1 |
| Recordable injury and illness cases in ship building and repairing, 2024 | 5.3 thousand | BLS SOII 2024, Table 2 |
| OSHA action level vs permissible exposure limit (8-hour average) | 85 vs 90 dBA | OSHA 29 CFR 1910.95 |
| OSHA standard threshold shift (average change at 2000, 3000 and 4000 Hz) | 10 dB or more | OSHA 29 CFR 1910.95 |
| EU daily exposure limit vs upper vs lower action value | 87 vs 85 vs 80 dB(A) | Directive 2003/10/EC |
| EU peak limit vs upper vs lower action value | 140 vs 137 vs 135 dB(C) | Directive 2003/10/EC |
| US workers exposed to hazardous noise (85 dBA or higher) each year | About 27 million | NIOSH Noise and Hearing Loss |
| Korean workers with suspected occupational disease in 2024 screenings whose finding was noise-related hearing loss | 31,709 of 32,088 (98.8%) | Korea Ministry of Employment and Labor 2024 data, via Korea Times 2026 |
Context note: the Korean screening figure covers all industries, not shipbuilding alone. The 37 percent claimant-age figure is the committee’s statement in a request letter, not a GAO finding; the GAO review had not been published when we checked.
Summary: Shipyard Sandblasting and Welding Acoustic Overexposure by the Numbers
| Metric | Value | Source |
|---|---|---|
| Abrasive blasting, typical sound level | 105 to 112 dBA | OSHA Shipyard Employment eTool |
| Needle gunning, typical sound level | 113 dBA | OSHA Shipyard Employment eTool |
| Abrasive blasters, full-shift exposure under OSHA criteria (4 workers) | 100.0 to 108.1 dBA | NIOSH HHE Report 2023-0084-3425, 2025 |
| Daily time OSHA permits at 100 dBA | 2 hours | OSHA 29 CFR 1910.95 |
| US shipyard full-shift samples above 90 dBA | 13 of 30 (43%) | NSRP 2012 |
| Korean shipbuilding samples above the limit, OSHA method | 629 of 1,575 (39.9%) | Shin et al., IJERPH 2021 |
| Lunch-break noise, Korean “power” tasks | 100.9 dBA | Shin et al., IJERPH 2021 |
| Shanghai shipyard workers with a threshold above 25 dB HL | 80.5% | Jiang et al., JAMA Network Open 2021 |
| Annual decline at 12.5 kHz, young shipyard workers | 2.70 dB per year | Jiang et al., JAMA Network Open 2021 |
| New speech-frequency hearing loss, male shipyard workers, mean 5.34 years | 15.3% | Yu et al., Communications Medicine 2026 |
| Pooled hearing impairment, industrial workers worldwide | 28.8% | Salari et al., 2024 |
| Hearing loss: subcontracted vs permanent Turkish shipyard workers | 42% vs 21.88% | Azkeskin and Arikan Ozturk, 2019 |
| Indonesian ship-repair workers with sensorineural hearing loss | 81.2% | Sincihu et al., IJOSH 2019 |
| Indonesian ship-repair workers who never wore ear protectors | 45.3% | Sincihu et al., IJOSH 2019 |
| Torch cutter peak level, ship recycling yard | 144.0 dB(C) | Kurt et al., Ocean Engineering 2017 |
| US workers exposed to hazardous noise each year | About 27 million | NIOSH Noise and Hearing Loss |
| Ship building and repairing injury and illness rate vs manufacturing | 4.8 vs 2.7 per 100 workers | BLS SOII 2024 |
| EU daily noise exposure limit | 87 dB(A) | Directive 2003/10/EC |
Methodology and Sources
- NIOSH Health Hazard Evaluation Report 2023-0084-3425 (2025): metal and noise exposures at a shipbuilding and ship repair company, sampled April 2024; summarized in AIHA news, February 2026.
- OSHA Shipyard Employment eTool, Hearing Protection and OSHA 29 CFR 1910.95.
- NSRP, Noise Control Methods for Shipbuilding, Final Report 2012 (Atrium Environmental Health and Safety Services).
- Shin, Lee, Lee and Kim, IJERPH 2021, 18, 8847: unmeasured break time in Korean shipbuilding noise assessment.
- Kim and Chung, Journal of Preventive Medicine and Public Health 2003 and Choi and Kim, PLoS One 2014.
- Jiang et al., JAMA Network Open 2021 and Yu et al., Communications Medicine 2026: Chinese shipyard audiometry cohorts.
- Salari et al., Indian Journal of Otolaryngology and Head and Neck Surgery 2024: global meta-analysis of industrial hearing impairment.
- Azkeskin and Arikan Ozturk, Evaluation of Noise Exposure in Shipbuilding Sector, 2019 and Sincihu et al., IJOSH 2019.
- Kurt, McKenna, Gunbeyaz and Turan, Ocean Engineering 2017: noise in a ship recycling yard.
- US Bureau of Reclamation, Sandblasting Noise Project 2016 and Lindsey, Montana Tech 2016.
- BLS Survey of Occupational Injuries and Illnesses 2024, Table 1 and Table 2.
- EU Directive 2003/10/EC on noise, NIOSH Noise and Hearing Loss, House Education and Workforce Committee letter to GAO, September 2025, and Korea Ministry of Employment and Labor 2024 screening data as reported by the Korea Times.
- For sector-wide context beyond shipyards, see our occupational noise exposure in manufacturing statistics.
- Data watch: much of the shipyard-specific evidence is older than three years (NSRP 2012, Kurt et al. 2017, Turkish and Indonesian studies 2019, Korean dosimetry from 2016 to 2018), and we flag it as most recent available data. The NIOSH evaluation covers one company and reports no audiometric results, so its exposures are not industry averages. Prevalence figures depend on the definition: “any frequency above 25 dB HL” (80.5%, Jiang et al.) is not comparable with speech-frequency loss (65.1%, Yu et al.). The Turkish abstract reports 36% and 42% vs 21.88% without stating the denominators for each subgroup, and Kurt et al. report 25 area measurements in one section and 26 in another. BLS Tables 1 and 2 do not break out hearing loss, so the 4.8 rate covers all recordable injury and illness cases. The GAO review of Longshore Act claims requested in September 2025 had not been published when we checked. Several sources here (Korean screening data, the global meta-analysis, the NIOSH 27 million estimate) cover all industries and are labelled as context, not shipyard figures.
Last updated: October 18, 2026. We update this roundup quarterly, and the next refresh is expected when GAO publishes its review of Longshore and Harbor Workers’ Compensation Act hearing-loss claims and BLS releases its 2025 Survey of Occupational Injuries and Illnesses.