Electric Utility Workers Research Articles

Prevalence of musculoskeletal pain and dysfunction in electrical utility workers: Practical considerations for prevention and rehabilitation in the workplace.

This study assessed the prevalence and associations of musculoskeletal pain and dysfunction in electrical utility workers, with the aim of applying the findings to better prevent and rehabilitate workplace musculoskeletal disorders. Employees completed an online survey recording their musculoskeletal symptoms across nine anatomical locations for the preceding 12 months. A total of 565 employees, working across eight different electrical utility organisational work units, completed the survey. The study was collaborative and conducted in Australia's largest, wholly government owned electricity company. The study originated from the participating organisation wanting to better understand their musculoskeletal disorder (MSD) risks. Employees who experienced high job stress were 4.06 times (95% confidence interval [CI] = 1.78-9.29) more likely to report musculoskeletal symptoms in the shoulder compared with employees with lower reported job stress. Employees that perceived their work to have high physical demands report lower back musculoskeletal symptoms at 2.64 times the rate of those perceiving their job to be of low physical demand (95% CI = 1.44-4.84). There were significant differences in the lower back musculoskeletal symptoms according to work unit membership. Understanding the prevalence of MSDs is critical to implementing practical prevention and rehabilitation strategies in the workplace. This anonymous survey highlighted that a large proportion of electrical utility workers reported that musculoskeletal symptoms had impacted their ability to perform their job, housework and/or hobbies in the preceding 12 months. Early access to rehabilitation services is essential. However, many workers report barriers to disclosing MSDs; therefore, workplace rehabilitation services may need to be broadened to account for these barriers.

Do Head-Mounted Augmented Reality Devices Affect Muscle Activity and Eye Strain of Utility Workers Who Do Procedural Work? Studies of Operators and Manhole Workers.

ObjectiveThe objective was to determine the effect of two head-mounted display (HMD) augmented reality (AR) devices on muscle activity and eye strain of electric utility workers. The AR devices were the Microsoft HoloLens and RealWear HMT-1.BackgroundThe HoloLens is an optical see-through device. The HMT-1 has a small display that is mounted to the side of one eye of the user.MethodTwelve power plant operators and 13 manhole workers conducted their normal procedural tasks on-site in three conditions: HoloLens, HMT-1, and “No AR” (regular method). Duration of test trials ranged up to 30 s for operators and up to 10 min for manhole workers. Mean and peak values of surface electromyographic (sEMG) signals from eight neck muscles were measured. A small eye camera measured blink rate of the right eye.ResultsIn general, there were no differences in sEMG activity between the AR and “No AR” conditions for both groups of workers. For the manhole workers, the HoloLens blink rate was 8 to 11 blinks per min lower than the HMT-1 in two tasks and 6.5 fewer than “No AR” in one task. Subjective assessment of the two AR devices did not vary in general.ConclusionThe decrease in blink rate with the HoloLens may expose utility manhole workers to risk of eye strain or dry-eye syndrome.ApplicationHMD AR devices should be tested thoroughly with respect to risk of eye strain before deployment by manhole workers for long-duration procedural work.

Characterizing Heat Stress and Strain in Electric Utility Workers by Means of a Questionnaire

In recent field work we showed that the high physical demands combined with restrictions to heat loss due to protective work uniforms caused some electric utility workers to experience dangerous levels of hyperthermia (J Occup Environ Hyg. 2015;12:708). These findings indicate that heat stress in the electric utility industry may be detrimental to worker health and safety. In the present study, 414 workers in the power generation and delivery industry across 15 US states completed a two‐part on‐line questionnaire anonymously. Part 1 comprised 15 general questions on the worker's age, sex, role in the organization, general duties, workplace location, work shift duration, years of experience, level of physical activity, frequency of heat exposure, other. The second part consisted of a validated questionnaire for the assessment of heat stress at the workplace – the ‘Heat Strain Score Index (HSSI)’ (Int J Prev Med 2013; 4:631). It was composed of 18 questions which included key factors in heat stress evaluation (environmental parameters, work intensity, level of heat exposure, clothing insulation and permeability, etc.) and indicators of heat strain (sweat rate, fatigue, thirst, symptoms of heat‐related illness, etc.) with cut‐off scores as follows: ≤13.5, green zone or safe level; 13.6 to 18.0, yellow zone or alarm level; >18.0, red zone or danger level. The average (±SD) age of the respondents was 46(10) years and they reported being in their present position for 11(10) years. They typically performed 5(1) consecutive days of work lasting 10(6) hours each day. For all job types (all workers), 79% of respondents reported heat stress was a problem. This number was greater (93%) in those performing physically demanding jobs (e.g. linesman). Further, 30% and 67% of all workers indicated they were exposed to heat stress occasionally and daily, respectively. In contrast, 81% of linesman reported being exposed to heat stress on a daily basis with only 19% experiencing occasional exposure. Based on the HSSI, 43% of all workers and 68% of linesman were categorized in the red zone (danger level) and therefore at an elevated risk of a heat‐related injury (both p<0.01). Our findings demonstrate that electric utility workers are likely to experience excessive heat strain and research must be conducted to explore methods to effectively and efficiently manage heat stress and strain in these workers.Support or Funding InformationHuman and Environmental Physiology Research Unit (G.P. Kenny).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The physical demands of electrical utilities work in North America

ABSTRACTWe assessed the physical demands associated with electrical utilities work in North America and how they influence the level of thermal and cardiovascular strain experienced. Three common job categories were monitored as they are normally performed in thirty-two electrical utility workers: (i) Ground Work (n = 11), (ii) Bucket Work (n = 9), and (iii) Manual Pole Work (n = 12). Video analysis was performed to determine the proportion of the work monitoring period (duration: 187 ± 104 min) spent at different levels of physical effort (i.e., rest as well as light, moderate and heavy effort). Core and skin temperatures as well as heart rate were measured continuously. On average, workers spent 35.9 ± 15.9, 36.8 ± 17.8, 24.7 ± 12.8, and 2.6 ± 3.3% of the work period at rest and performing work classified as light, moderate, and heavy physical effort, respectively. Moreover, a greater proportion of the work period was spent performing heavy work in Ground Work (1.6 ± 1.4%) relative to Bucket Work (0.0 ± 0.0%; P<0.01) and in Manual Pole Climbing (5.5 ± 3.6%) in comparison to both other work job (both P≤0.03). Furthermore, the proportion of time spent during work classified as heavy physical effort was positively correlated to the mean (r = 0.51, P<0.01) and peak (r = 0.42, P = 0.02) core temperatures achieved during the work period as well as the mean heart rate response (presented as a percentage of heart rate reserve; r = 0.40, P = 0.03). Finally, mean and peak core temperatures and mean heart rate responses increased from the first to the second half of the work shift; however, no differences in the proportion of the work spent at the different intensity classifications were observed. We show that Manual Pole Work is associated with greater levels of physical effort compared to Ground or Bucket Work. Moreover, we suggest that the proportion of time spent performing work classified as heavy physical exertion is related to the level of thermal and cardiovascular strain experienced and that workers may not be employing self-pacing as a strategy to manage their level of physiological strain.

Breast cancer screening utilization and understanding of current guidelines among rural U.S. women with private insurance.

Women living in rural areas of the U.S. face disparities in screening mammography and breast cancer outcomes. We sought to evaluate utilization of mammography, awareness of screening guidelines, and attitudes towards screening among rural insured U.S. women. We conducted a cross-sectional self-administered anonymous survey among 2000 women aged 40-64 insured by the National Rural Electric Cooperative Association, a non-profit insurer for electrical utility workers in predominantly rural areas across the U.S. Outcomes included mammographic screening in the past year, screening interval, awareness of guidelines, and perceived barriers to screening. 1588 women responded to the survey (response rate 79.4 %). 74 % of respondents lived in a rural area. Among women aged 40-49, 66.5 % reported mammographic screening in the past year. 46 % received annual screening, 32 % biennial screening, and 22 % rare/no screening. Among women aged 50-64, 77.1 % reported screening in the past year. 63 % received annual screening, 25 % biennial screening, and 12 % rare/no screening. The majority of women (98 %) believed that the mammography can find breast cancer early and save lives. Less than 1 % of younger women, and only 14 % of women over age 50 identified the recommendations of the U.S. Preventative Services Screening Task Force as the current expert recommendations for screening. Screening practices tended to follow perceived guideline recommendations. When rural U.S. women over age 40 have insurance, most receive breast cancer screening. The screening guidelines of cancer advocacy groups and specialty societies appear more influential and widely recognized than those of the U.S. preventative services taskforce.

An Evaluation of the Physiological Strain Experienced by Electrical Utility Workers in North America

The purpose of this study was to assess the physiological strain experienced by North American electrical utility workers during the performance of their normal work duties in heat stressed conditions. Three common job categories were monitored as they are normally performed in 32 electrical utility workers: (i) Ground Work (n = 11); (ii) Bucket Work (n = 9); and (iii) Manual Pole Work (n = 12). Worker hydration status (urine specific gravity (USG)) was measured prior to and following the work monitoring period (duration: 187 ± 104 min). Core and skin temperatures as well as heart rate were measured continuously. Physiological Strain Index (PSI) was calculated from the measurements of core temperature and heart rate. Prior to the start of the work shift, 38% of workers were euhydrated (USG < 1.020; n = 12) whereas the majority of workers were dehydrated (USG > 1.020; prevalence: 75%; p < 0.01) following work. The overall mean and peak core temperatures for all monitored workers were 37.9 ± 0.3°C and 38.3 ± 0.5°C, respectively. When responses were compared between job categories, greater mean and peak increases in core temperature were observed in Manual Pole Work relative to the other job categories (both p < 0.04). In fact, six workers performing Manual Pole Work achieved core temperatures in excess of 38.5°C, while only one other worker surpassed this threshold in Bucket Work. The high levels of thermal strain were paralleled by elevated mean and peak heart rate and PSI responses, which were greater in Manual Pole Work in comparison to the other job categories (all p ≤ 0.05). Furthermore, two workers performing Manual Pole Work achieved severely elevated core temperatures reaching or exceeding 39.5°C along with prolonged periods of near maximal heart rate responses (i.e., >90% of heart rate reserve). We report elevated levels of thermal and cardiovascular strain in electrical utility workers during work in the heat and potentially dangerous levels of hyperthermia during particularly strenuous work.

An Evaluation of the Physiological Strain Experienced by North American Electrical Utility Workers

Electrical power workers must often perform physically demanding tasks in hot and humid environments while wearing heavy insulated clothing. However, little is known about the physiological strain experienced by these workers. PURPOSE: To assess the physiological strain experienced by electrical utility workers during their daily work shifts performed in the heat (29.0-34.4°C). METHODS: Five typical electrical utilities jobs were evaluated in a total of 32 electrical utilities workers (age: 36 ± 9 years; body weight: 97 ± 17 kg): (i) General Labour (n=6), (ii) Bucket Work (n=9), (iii) Networking (n=5), (iv) Combined Work (n=9), and (v) Pole Climbing (n=3). Hydration status was assessed prior to work using urine specific gravity (USG). Core temperature (assessed using a telemetric pill) and heart rate (HR) responses were measured continuously. RESULTS: Before the start of the work period, five participants were considered well hydrated (USG≤1.010; prevalence: 15.6%), six of the participants were classified as seriously dehydrated (USG>1.030; prevalence: 18.8%), with the remaining participants considered as either minimally (n=9; USG: 1.021-1.030; prevalence: 28.1%) or significantly dehydrated (n=13; USG: 1.021-1.030; prevalence: 40.6%). Mean resting core temperature was 37.2 ± 0.3°C. During the work shift average core temperature responses ranged from 37.7 ± 0.1°C in Networking to 38.0 ± 0.4°C in Combined Work while the peak core temperature achieved by a single participant exceeded 38.3°C in all work categories (General Labour, 38.6°C; Bucket Work, 38.7°C; Network 38.4°C; Combined Work, 39.7°C; Pole Climbing, 38.7°C). Furthermore, two participants performing Combined Work experienced severe levels of heat stress reaching peak core temperatures of ∼39.6°C. These individuals spent ∼50% of the 4.5 hour work period at core temperatures exceeding 38.5°C. Mean HR ranged from 31 ± 8 to 57 ± 16 percent of participants’ age predicted HR rate reserve (HRR). Peak HR rate responses achieved levels ≥93% HRR for all jobs with the exception of networking (General Labour: 98%; Bucket Work: 94%; Combined Work: 93%; Pole Climbing: 104%). CONCLUSIONS: We show that electrical utility workers performing common jobs in the heat start their shift in a dehydrated state and experience elevated levels of thermal and cardiovascular strain, resulting in an increased risk for heat-related injuries. SUPPORT: Electrical Power Research Institute.

Working in Hot Conditions—A Study of Electrical Utility Workers in the Northern Territory of Australia

Environmental conditions of Australia's Northern Territory are seasonally conducive to excessive body heat storage by outdoor workers. For electrical utility workers who periodically work at height, in confined space, and in proximity to live power sources, the impact of the climate may be considered a hazardous condition. Therefore, this study examined the physiological and fluid balance responses of 20 power network workers (31.5 years; 86.0 kg; 1.71 m; BMI 29.5) throughout work shifts in the Northern and Southern regions of the Northern Territory, Australia.Twenty male heat-acclimatized power network workers provided written informed consent to be monitored during maintenance of electrical infrastructure that included replacing power pole components and transformer and substation repairs in the Northern (n = 13) and Southern regions (n = 7) of the Northern Territory (mean wet-bulb globe temperatures of 32.0°C and 28.7°C, respectively). An ingestible telemetry pill provided measurement of gastrointestinal temperature (Tgi), that when combined with heart rate values, provided physiological strain index (PSI). Urine specific gravity, sweat rate, and level of dehydration were also determined.The Tgi values of this study were within the ISO9886 limit for monitored, heat-acclimatized workers, with a peak of 38.4°C. Mean PSI was 2.6, which represents overall low strain, with periods of moderate strain. Urinary analysis indicated that workers were dehydrated prior to and following the work shift, however the mean sweat rate of 0.44 L.h−1 was matched by fluid consumption of 0.42 L.h−1 to limit body mass loss to 0.1% during the shift.This study demonstrates that heat acclimatized electrical utility workers adhere to ISO9886 requirements when undertaking self-paced activity in hot conditions.

Comfort and performance of power line maintainers' gloves during electrical utility work in the cold

Electrical utility workers wear thick rubber gloves and often work in the cold. To document the challenge of working in the cold and the effectiveness of different glove/liner combinations in keeping workers' hands warm. Ten experienced male electrical utility employees worked in a controlled temperature walk-in chamber at -20 °C for 45 minutes for each of five glove conditions: standard five-finger rubber gloves with cotton liners and gauntlets, mitten style gloves, a prototype wool liner, and two heating options; glove or torso. Dependent measures were maximum grip force, skin temperatures, finger dexterity and sensitivity to touch, ratings of perceived effort and a rating of thermal sensation. Participants' hand skin temperatures decreased, they perceived their hands to be much colder, their finger sensitivity decreased and their ratings of perceived exertion increased, however their performance did not degrade over the 45 minute trials. The mitten-style gloves showed a smaller drop in skin temperature for the 3rd and 5th digits (p< 0.05) than the other glove conditions. Mitten style gloves kept workers' hands warmer than the standard five finger glove.

The Potential Bioeffects of Extremely Low Frequency Electromagnetic Fields on Melatonin Levels &amp;amp; Related Oxidative Stress in Electric Utility Workers Exposed to 132 kV Substation

Electricity substations take electricity from power lines and transformer lines to transform it from high to low voltage and distribute to the consumers. These substations generate low frequency electromagnetic fields similar to those emitted from over head power lines and electrical appliances at home. The present study is focused on assessing the potential bioeffects of Extremely Low Frequency Electromagnetic Fields (ELF-EMFs) on melatonin level and oxidative stress biomarkers, in subjects occupationally exposed to 132 kV high voltage substation in Hyderabad, India. These subjects are involved in maintenance and installation of power line distribution at electricity transmission network. The ELFEMFs exposed subjects (n = 142) included the electric utility workers, who were compared with age, and socioeconomic status matched controls (n = 151). The subjects were professionally categorized based on their job titles, with different exposure levels, as administrative workers (low exposure), maintenance workers (medium exposure) and liveline workers (high exposure). The plasma melatonin levels were significantly suppressed in the high exposed subjects i.e., hotline workers (p 0.05). The oxidant status levels of plasma Malondialdehyde (MDA) and Nitric Oxide (NO) showed significantly increased levels in all the exposed subjects (p 0.05). The activity levels of erythrocyte antioxidative enzyme when compared to control subjects were significantly reduced in the exposed subjects of all the categories (p 0.05).

Are posture data from simulated tasks representative of field conditions? Case study for overhead electric utility workers

Many ergonomics studies are conducted in laboratory-simulated work environments to assess risks for the development of musculoskeletal disorders under more controlled conditions. However, the simulated conditions could be of questionable validity with respect to reproduction of field conditions involving risk factors. The objective of this study was to verify whether the postures recorded for neck extension/flexion and upper arm elevation of overhead electric utility workers in a simulated environment were similar to those recorded in a field environment. Of the three frequently performed tasks analysed, two presented similar exposure in both conditions. However, differences were identified for a more complex task (relay replacement). These results suggest that simulated tasks may be more representative for more standardised tasks. This may indicate that researchers investigating risks should avoid simplifying complex tasks when reproducing field posture exposure in laboratories, since omitting extra subtasks may lead to an inaccurate reproduction of field exposure. Practitioner Summary: Studies comparing results from field and simulated environments are necessary to evaluate to what degree postural exposure reproduced in laboratory is representative of the exposure occurring in real work situations. This is particularly relevant for tasks involving training in simulated environment due to safety constraints.

Comparison of five approaches to keeping power line maintainers’ hands warm during work in the cold

Electric utility workers in Canada must frequently work in the cold and must wear thick rubber gloves which can result in rapid fatigue and reduced performance. The purpose of the study was therefore to document the challenge of working in the cold wearing the standard five-finger rubber gloves and covers and compare them to two equipment options, mitten style gloves or a prototype wool liner, and two heating options, glove or torso heating. The dependent measures were grip force, temperature, dexterity (modified Purdue pegboard test and a simulated occupational task), finger sensitivity (Von Frey hair test), perceived effort and thermal sensation. The study population consisted of 10 experienced male utility workers. They worked in a controlled temperature walk-in chamber (-20 degrees Celsius) and performed simulated utility work for 45 minutes with interspersed test batteries. The mitten style glove and woolen liner in a standard glove reduced the effects of working in the cold compared to the standard five-fingered variety with a thin cotton liner. We found that the mitten style glove showed lesser drops in skin temperature for the 3rd and 5th digits than the other conditions (p < 0.05).

A collaborative effort to apply ergonomics to electric utility workers at generating stations

As part of a collaborative approach involving electric utility companies, university researchers, individual contractors and a not-for-profit research institute, two ergonomics teams consisting of skilled utility workers and trained ergonomists, were assembled. These teams were to identify tasks with risk factors for musculoskeletal disorders (MSDs) among workers in fossil-fueled generating stations and and to propose ergonomic interventions for these tasks. One team focused on tasks of electricians and the other focused on tasks of plant operators and mechanics. Several of the tasks were tested in an ergonomics laboratory and at one of the utility's generating stations. We present a sample of the recommended interventions in this paper. An anthropometric analysis of electrical box height recommended the appropriate height for electrical boxes. The results of a field experiment showed that low rolling resistance wheels decreased the forces to initiate and sustain pushing a cart. The same experiment also demonstrated that the forces required to turn a cart with six wheels were lower than the forces equired to turn a cart with four wheels. A collaborative approach to ergonomics proved to be an effective method to identify and assess tasks that are problematic for workers and to develop best practices for these tasks in the electric power industry. This method could be used by other industries in their attempt to decrease the incidence, cost and severity of workplace MSDs.

Application of Electric Utility Workers' Anthropometry to Clearance between Vehicle Pedals and Adjacent Structures

Many electric utility fleet vehicles—notably pickups and vans—have limited clearance between the accelerator and brake pedal for workers who wear larger shoe sizes and even larger boots. The objectives of this study were to establish a analysis protocol for determining safe clearance between pedals and adjacent structures and then apply this protocol to existing utility fleet vehicles to determine which vehicles have adequate clearance for safe driving. Three sources of data were measured:1) detailed dimensions of the cabs of 16 common utility vehicles 2) anthropometric dimensions of 187 male electric utility field and generating station workers, including boot size and 3) width, length, and height of work boots, snow shoes, and rain slickers. Analysis revealed that many common fleet vehicles provide inadequate foot clearance between the pedals and adjacent structures, thus creating an unsafe driving condition. The approach of data collection and analysis of this study can be applied to other types of vehicles in order to determine the safety of pedal design, particularly risk of “unintended acceleration.”

Analyzing digital vector waveforms of 0–3000 Hz magnetic fields for health studies

To improve the assessment of magnetic field exposures for occupational health studies, the Multiwave System III (MW3) was developed to capture personal exposures to the three-dimensional magnetic field vector B(t) in the 0-3000 Hz band. To process hundreds of full-shift MW3 measurements from epidemiologic studies, new computer programs were developed to calculate the magnetic field's physical properties and its interaction with biological systems through various mechanisms (magnetic induction, radical pair interactions, ion resonance, etc.). For automated calculations in the frequency domain, the software uses new algorithms that remove artifacts in the magnetic field's Fourier transform due to electronic noise and the person's motion through perturbations in the geomagnetic field from steel objects. These algorithms correctly removed the Fourier transform artifacts in 92% of samples and have improved the accuracy of frequency-dependent metrics by as much as 3300%. The output of the MwBatch software is a matrix of 41 exposure metrics calculated for each 2/15 s sample combined with 8 summary metrics for the person's full-period exposure, giving 294 summary-exposure metrics for each person monitored. In addition, the MwVisualizer software graphically explores the magnetic field's vector trace, its component waveforms, and the metrics over time. The output was validated against spreadsheet calculations with pilot data. This software successfully analyzed full-shift MW3 monitoring with 507 electric utility workers, comprising over 1 million vector waveforms. The software's output can be used to test hypotheses about magnetic field biology and disease with biophysical models and also assess compliance with exposure limits.

Neck Injuries Among Electric Utility Workers, 1995–2007

To describe the incidence and impact of neck injuries among electric utility workers. Rates of neck injuries per 10,000 employee-years were calculated for various demographic and occupational factors using data from an injury surveillance database established among 17 electric utility companies over the period 1995-2007. The overall rate of neck injuries was 13.3. Male workers had a slightly higher rate than females, and younger workers (<30) had the highest neck injury rates. Trade/craft workers experienced the highest rates of neck injuries, whereas office-based experienced the lowest. The majority of neck injuries (69%) were sprain/strains and resulted in less than 1 lost day of work (76.7%). The occurrence of neck injuries in the electric utility workforce varies widely with respect to age, sex, and occupational groups with different characteristics, activities, and work environments. Industry-wide surveillance allows easier identification of injury patterns and risk factors of various injury types and facilitates the development of targeted prevention and intervention strategies to reduce the occurrence of these injuries.

Bias in the estimation of exposure effects with individual- or group-based exposure assessment

In this paper, we develop models of bias in estimates of exposure-disease associations for epidemiological studies that use group- and individual-based exposure assessments. In a study that uses a group-based exposure assessment, individuals are grouped according to shared attributes, such as job title or work area, and assigned an exposure score, usually the mean of some concentration measurements made on samples drawn from the group. We considered bias in the estimation of exposure effects in the context of both linear and logistic regression disease models, and the classical measurement error in the exposure model. To understand group-based exposure assessment, we introduced a quasi-Berkson error structure that can be justified with a moderate number of exposure measurements from each group. In the quasi-Berkson error structure, the true value is equal to the observed one plus error, and the error is not independent of the observed value. The bias in estimates with individual-based assessment depends on all variance components in the exposure model and is smaller when the between-group and between-subject variances are large. In group-based exposure assessment, group means can be assumed to be either fixed or random effects. Regardless of this assumption, the behavior of estimates is similar: the estimates of regression coefficients were less attenuated with a large sample size used to estimate group means, when between-subject variability was small and the spread between group means was large. However, if groups are considered to be random effects, bias is present, even with large number of measurements from each group. This does not occur when group effects are treated as fixed. We illustrate these models in analyses of the associations between exposure to magnetic fields and cancer mortality among electric utility workers and respiratory symptoms due to carbon black.

An Integrated Job Exposure Matrix for Electrical Exposures of Utility Workers

Electric utility workers may be exposed to any combination of magnetic fields, electric fields, nuisance shocks (from spark discharges and continuous currents), imperceptible contact currents, and electrical injuries. Collectively these exposures are referred to as EMF Factors. Previous occupational exposure assessments have mainly characterized the magnetic field, with less attention to the electric field. Nuisance shocks and electrical injuries, though palpable, have received little to no attention. This article presents a prototype job exposure matrix that addresses exposure to all EMF Factors taking into account job category, work environment, and occupied environment. Exposures for all factors were classified into three ordinal levels for 22 job categories. Electric and magnetic field exposures were classified by the geometric mean of daily average of personal exposure measurements. Although relatively sparse, survey data on nuisance shocks were adequate for exposure assignment by job category and indicate that the frequency of these exposures has diminished over time. The least information was available for imperceptible contact currents that are associated with electric field exposures and small contact voltages. Data for electrical injuries by job category were derived from the Electric Power Research Institute Occupational Health Surveillance Database, with exposure assignments based on combined injury rates for flash burn and electric shock/electrocution. The highest exposures for all EMF Factors are essentially limited to four job categories that work on or close to electrical equipment: (1) cable splicers, (2) electricians, (3) line workers, and (4) substation operators. [Supplementary materials are available for this article. Go to the publisher's online edition of the Journal of Occupational and Environmental Hygiene for the following free supplemental resources: PDF files containing Appendix I: Job Exposure Matrix Elements and Appendix II: Nuisance Shock Surveys.]

Stress at Work among Electric Utility Workers

In the last decades there was an increase in stress at work and its effects on workers' health. These issues are still little studied in the electric utility sector. This study aims to evaluate factors associated with stress at work and to verify its associations with health status among workers of an electric company in São Paulo State, Brazil. A cross-sectional study was conducted with 474 subjects (87.5% of the eligible workers). Data were collected using self-reported questionnaires. A descriptive analysis, a multiple linear hierarchical regression analysis and a correlation analysis were performed. The majority of participants were males (91.1%) and the mean age was 37.5 yr. The mean score of stress level was 2.3 points (scale ranging from 1.0 to 5.0). Hierarchical multiple analyses showed that: regular practice of physical activities (p=0.025) and individual monthly income (p=0.002) were inversely associated with stress level; BMI was marginally associated with the stress level (p=0.074). The demographic characteristics were not associated with stress. Stress at work was significantly associated with physical and mental health status (p<0.001). To improve health of electric utility workers, actions are suggested to decrease stress by remuneration and an appropriate practice of physical activity aiming reduction of BMI.

Factors that distinguish serious versus less severe Strain and sprain injuries: An analysis of electric utility workers

Occupational sprain and strain injuries are one of the most common types of nonfatal occupational injuries and a significant source of lost workdays. This study examines factors associated with severe work-related sprain/strain injuries to the back, shoulder, and knees. A synthetic case-control study was performed (controls were selected from the same pool of utility workers as cases). Cases included all electric utility workers who had experienced a severe work-related sprain/strain injury to the back, knee, or shoulder. Primary controls were selected from all workers who had sustained a minor injury. Secondary controls were selected from employees with a minor sprain/strain injury to the back, knee, or shoulder. Multivariate logistic regression models were used to estimate odds ratios and 95% confidence intervals. Workers 41 years and older were more likely to have experienced severe shoulder sprain/strain injuries [Age 41-50: OR = 3.62, 95% CI: 1.71-7.65; age 51 and older: OR = 4.49, 95% CI: 1.89-10.67] and severe back sprain/strain injuries [Age 41-50: OR = 1.70, 95% CI: 1.06-2.33; age 51 and older: OR = 1.5, 95% CI: 0.90-2.52]. Line workers and maintenance workers had an increased risk of serious sprain/strain injuries. Gender and day of week were not significantly associated with sprain/strain injuries. Though this study is limited by available data, future studies may benefit from this preliminary examination of occupational and demographic characteristics associated with serious sprain/strain injuries among electric utility workers.