Occupational burn injuries represent a distinct subset of thermal trauma arising from high-risk industrial environments, including exposure to hot liquids, steam, electrical sources, flames, and chemical agents [1]. Compared to non-occupational burns, work-related burns are more likely to involve functionally critical sites such as the hands and upper extremities, may extend into deeper structures, and often require operative wound coverage. Long-term consequences, such as hypertrophic scarring, pain, hyperpigmentation, and post-burn scar contracture can result in prolonged disability and delayed return to work, thereby imposing a substantial clinical and socioeconomic burden [1].

While population-based incidence is ideal for quantifying societal burden, longitudinal changes in the institutional proportion of work-related burns can still be epidemiologically and policy-relevant as a surveillance metric. First, the proportion reflects the changing case-mix and clinical workload within a burn-care system, which is directly relevant to resource allocation and surgical capacity. Second, because work-related classification is tightly linked to recognition, documentation, and compensation pathways, the proportion can serve as a pragmatic indicator of reporting and workers’ compensation utilization within routine clinical practice. Accordingly, changes in proportion may inform both prevention priorities and injury-reporting practices even when an external population denominator is unavailable.

Although workplace safety regulations and hazard-awareness programs have strengthened over time, institutional epidemiological trends in work-related burn injuries in Korea remain insufficiently characterized. In particular, there is limited longitudinal evidence describing how the proportion of work-related burn admissions changes over time within a burn-care system, and how such changes relate to evolving industrial exposure patterns and reporting behaviors. Importantly, the observed proportion of work-related injuries can be influenced not only by true workplace exposure but also by access to and utilization of workers’ compensation systems. Underreporting of occupational injuries has been attributed to administrative barriers, limited knowledge of reporting pathways, fear of job loss or retaliation, and employer discouragement [2,3]. Conversely, growing public awareness of industrial accident compensation and gradual improvements in the reporting culture may increase the likelihood that injuries previously recorded as non-occupational are now identified and processed as work-related, thereby increasing the measured proportion without necessarily indicating an increase in the absolute incidence [2,3].

The COVID-19 pandemic has introduced additional challenges into interpreting long-term trends. Multiple burn center studies have reported that the pandemic has altered injury epidemiology and healthcare utilization, with shifts in admission volumes and burn mechanisms during periods of reduced industrial activity and mobility. Such a disruption can act as a structural break in the time-series data, producing abrupt and temporary changes in the observed proportion of work-related burns. In many settings, reduced industrial operations during 2020–2022 likely contributed to an artificial decline in occupational burn incidence and/or a change in the relative mix of occupational versus non-occupational burns, potentially confounding secular trend analyses if pandemic years are not addressed [4-7]. Alternative analytic frameworks, such as segmented regression and interrupted time series models, could explicitly model this interruption; however, these approaches require stronger assumptions and sufficient pre/post interruption time points.

Against this background, the present study aimed to evaluate the temporal changes in the proportion of work-related burns among all inpatients with burns over a 10-year period, with specific attention paid to the COVID-19 era and the possibility of pandemic-related distortion. In addition, this study aimed to describe the epidemiology and operative management of work-related burns, including sex, age, etiology, burn size and depth, injured body regions, complications, seasonal distribution, and reconstructive strategies. By clarifying how the institutional proportion changed over time and by explicitly cautioning against population-level inference, this analysis provides a pragmatic, within-center surveillance benchmark that complements international reports on occupational burn patterns.

A single-center retrospective observational study was conducted on inpatients with burns treated between 2016 and 2025 at Hanil General Hospital. Annual counts of total burn inpatients and work-related burn inpatients were obtained (n=5,074 overall, n=535 work-related). A work-related burn was defined as a burn injury recorded in the institutional dataset as an industrial accident or workers’ compensation case.

Because the denominator is the total number of burn inpatients treated at a single institution, the target population is an institutional patient population rather than a geographically defined catchment population. Accordingly, temporal changes in referral patterns, inter-hospital transfer practice, and healthcare utilization, particularly during the COVID-19 pandemic, could influence both the numerator and denominator, introducing selection bias. This study, therefore, interprets temporal changes as within-center changes in case-mix and documentation rather than population-level incidence.

Demographic variables (age and sex), injury characteristics (primary etiology, total body surface area [TBSA], and burn depth), anatomical distribution (head/neck, trunk, upper extremity, and lower extremity), clinical outcomes (complications and length of stay), seasonal distribution (spring, summer, autumn, and winter), and operative management information were collected. Operative management was defined as at least one surgical procedure for definitive wound coverage or related burn care. The surgical procedures were categorized as split-thickness skin grafting (STSG), STSG with acellular dermal matrix (ADM), full-thickness skin grafting (FTSG), local flap, pedicled abdominal flap, pedicled groin flap, free flap, and amputation.

Annual work-related proportions were calculated as work-related burn inpatients/total burn inpatients×100. Period comparisons were performed using a two-proportion test (2016–2019 vs. 2020–2022 and 2020–2022 vs. 2023–2025). In addition, to account for multi-period comparisons, an overall 2×3 comparison across the three periods was performed using a chi-square test, depending on expected cell counts. Because the COVID-19 period (2020–2022) was associated with marked changes in burn-related admissions in prior studies [4-7], a secular trend analysis was additionally performed after excluding 2020–2022 by fitting a linear regression model of the annual proportions of work-related burns for 2016–2019 and 2023–2025. This exclusion was chosen to estimate the underlying secular trend outside the pandemic-related structural break; alternative approaches were considered but were not selected as the primary model given the abrupt, time-limited disruption and the goal of estimating non-pandemic secular change. This study also presents full period (2016–2025) descriptive results to contextualize the primary analysis.

This 10-year single-institution analysis showed that, despite a marked decline in total burn-related admissions between 2016 and 2025, the proportion of work-related burns increased over time after excluding the COVID-19 period (2020–2022). Importantly, this outcome represents a relative change in institutional case-mix (work-related burns among all burn inpatients) rather than population-level incidence, because a general population denominator and a stable catchment population were not available. Therefore, the findings should be interpreted as within-center surveillance rather than as representative of societal trends. Work-related burns accounted for 10.5% of all burn inpatients, and their annual proportion decreased significantly during 2020–2022 before rebounding in 2023–2025. This pattern is consistent with international reports indicating that the pandemic altered burn admissions, exposure patterns, and occupational contexts of injury [4-7]. Rather than treating the pandemic solely as a nuisance, the analytic choice reflects the conceptualization of 2020–2022 as a structural break in patient flow and exposure context; accordingly, the study prioritized estimation of the non-pandemic secular pattern.

The epidemiological characteristics of work-related burns included a male predominance and a substantial burden among middle-aged to older adults. Scalding and electrical injuries were the most common etiologies. Although most injuries involved <10% TBSA, operative management was required in more than half of patients, most frequently using graft-based reconstruction (STSG and STSG with ADM). This dissociation—small TBSA yet high operative rate (54.6%)—is clinically meaningful and suggests that many work-related burns occur in functionally critical regions, such as hands and feet, and involve deep tissue injury requiring definitive coverage, even when the overall burn size is limited. These features emphasize the need for early functional assessment, timely reconstructive planning, and structured rehabilitation and scar surveillance in occupational burn patients. This highlights that relatively small-area occupational burns may still necessitate surgery when burn depth is significant or when functionally critical regions such as the hands and feet are involved. The observed complication profile, particularly hypertrophic scarring and pain, further underscores the importance of structured long-term scar management and functional rehabilitation in this population.

Several mechanisms may account for the increasing proportion of work-related burns despite an overall reduction in total burn admissions. First, a denominator effect may occur if non-occupational burns decline more rapidly than occupational burns, resulting in a relative increase in the occupational share even without an increase in absolute occupational case numbers [8]. Second, the observed proportion could increase with improved recognition and reporting of occupational injuries and greater utilization of workers’ compensation systems [9]. Underreporting of work-related injuries is well documented and is associated with limited knowledge of reporting procedures, administrative burden, job insecurity, fear of retaliation, and employer discouragement [10-12]. In Korea, increasing awareness of industrial accident compensation and gradual reductions in stigma, together with strengthened oversight of informal or illegal compensation practices, may promote more appropriate claim filing and more accurate classification of work-related injuries within hospital records [11]. These interpretations should be regarded as hypothesis-generating, because we did not directly measure changes in compensation policy, reporting behavior, or industrial exposure intensity over time. Third, workforce and industry changes, including an aging workforce and sustained exposure in specific occupational sectors, may contribute to persistent occupational burn risk even as overall burn incidence decreases.

The seasonal peak in summer suggests that prevention strategies may benefit from seasonal preparedness and targeted workplace safety campaigns. Previous studies have reported seasonal variations in burn incidence and mechanisms [13], and increased work intensity, heat-related operational hazards, and shifts in industrial activity during warmer months may plausibly contribute to higher occupational burn risk.

This study is subject to selection bias because the denominator comprises burn inpatients treated at a single institution rather than a defined population at risk. Temporal changes in referral patterns, inter-hospital transfer systems, and healthcare utilization—particularly during the COVID-19 pandemic—may have altered both the numerator and denominator, potentially inflating or deflating the observed proportion independent of true occurrence. In addition, misclassification of work-related status is possible because classification relied on institutional documentation of industrial accident or workers’ compensation status; underreporting or delayed claim filing could bias estimates toward lower proportions in certain periods. Because workforce denominators were unavailable, we could not estimate incidence rates, and generalization to societal trends should be avoided. The limitations section accurately lists key constraints but could be strengthened by explicitly discussing how these limitations may bias the observed trends and their interpretation. Nonetheless, the decade-long observation period provides a valuable institutional benchmark and demonstrates a consistent increase in the proportion of documented work-related burns in the years before and after the COVID-19 pandemic. Collectively, these findings emphasize the need for continued workplace prevention strategies, accurate reporting of occupational injuries, and sustained postoperative scar and functional surveillance for affected workers.