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Background:Balance skills are challenged at the roofing worksite by dynamic visual cues in the form of clouds and trees that move with the wind; any instability may result in a fall from height.Aim:To determine if roofers are less susceptible to a dynamic visual surround (moving room) when stationary cues were available, relative to people who do not work in a similar environment.Methods:Forty male adults participated, including young roofers (N=10,26.3 years), middle-aged roofers (N=10,50.6 years), young controls (N=10,26.2 years) and middle-aged controls (N=10,55.1 years). Center of pressure root mean square (APRMS) was assessed during quiet standing and four moving room conditions when stationary cues were:(1)not in place,(2)in the foreground (inside the moving room),(3)in the background (outside the moving room, but still visible) and (4)in the foreground and background. Results:A workgroup by visual cue interaction was observed (p=0.032), where roofers had up to 18% lower APRMS relative to controls when the background references were in place. The interaction effect was independent of age. Interpretation:The roofers were able to suppress visually-induced postural sway when stationary visual cues were present in the background, likely due to the severe consequences for loss of balance when working at height. The suppression was maintained in aging workers.

The goal of this project was to use ergonomic design principles to evaluate a 3-dimensional computer simulation of a manikin in a clinical laboratory setting for individuals with lower limb disabilities. The first step was to use the University of Michigan 3D Static Strength Prediction Program (3D SSPP) to determine biomechanical challenges from three simulated work postures commonly performed among clinical workers. Findings were then imported into the Purdue Envision Center’s 3D simulation of the Accessible Biomedical Immersion Laboratory (ABIL) located at Purdue’s Discovery and Learning Research Center (DLRC). Positions assumed in the 3D ABIL simulation for each task were predicted, using the 3D SSPP software, to be achievable by at least 90% of the population. Collection of data from four subjects performing standardized clinical tasks while in wheelchairs allowed for real-world validation of the 3D simulation model. Additional ergonomic analysis was conducted using the Rapid Upper Limb Assessment (RULA) tool along with subject questionnaires to determine upper limb work risk factors associated with clinical tasks and workstations. RULA and questionnaire data showed the presence of potential upper limb risk factors that may need to be incorporated into the 3D simulation model, especially during pipetting tasks when performed by female subjects. This pilot study showed promise as a clinical facility design tool. Further research is needed to fine tune the 3D ABIL simulation as a useful tool to create clinical facilities for those with lower-limb disabilities.

Objectives To assess the determinants of airborne solvent exposures in contemporary vehicle collision repair workplaces. Methods Personal, full-shift airborne solvent exposures (n = 97) were assessed in 85 vehicle collision repair workers from 18 workshops. Peak exposures were assessed using a small number of video exposure monitoring measurements. Results Solvent exposures were highest in spray painters (geometric mean = 2.7 ppm) followed by panel beaters (0.5 ppm), but were well below workplace exposure standards. The lowest exposure levels were observed for mixing room extraction located away from the mixing bench [exposure ratio (ER) = 0.51, 95% confidence interval (CI) = 0.30-0.87]. Time spent mixing paint was associated with higher exposures (ER for every 10-min increase = 1.14, 95% CI = 1.05-1.24), as was time spent cleaning equipment with solvents (ER = 1.11, 95% CI = 0.88-1.39), spraying primer (ER = 1.10, 95% CI = 0.96-1.27), and spraying clear coat paint (ER = 1.07, 95% CI = 1.00-1.15). Overall, the combined non-spray painting tasks (mixing paint, degreasing, and cleaning equipment) were more strongly associated with exposure (ER = 1.10, 95% CI = 1.03-1.18) than the combined spray painting tasks (ER = 1.03, 95% CI = 1.00-1.05). Peak exposures ranged from 10 to 1100 ppm with the strongest and most frequent peaks occurring during paint mixing, decanting of solvents, cleaning of equipment, and painting in a cross-draft spray booth. Conclusions Airborne solvent exposures in the collision repair industry were associated with job title, the design and location of exhaust ventilation and emission sources, and time spent on specific tasks, with the highest average and peak exposures shown for non-spray painting tasks. These findings provide a contemporary basis for intervention programmes to reduce airborne solvent exposures in this industry.

Recent discoveries have shown that exhalation from patients in the postanesthesia care unit (PACU) exposed nurses to significant levels of WAGs based on administration of these anesthetic agents during the patient’s procedures. Nurses can have a critical role to help reduce these levels to the lowest level possible and improve the health of the interdisciplinary team. This chapter will outline the inhalation exposure hazards to nurses and present best practices, administrative, and engineering controls to prevent such exposures.

OBJECTIVES: To assess whether solvent use and workplace practices in the vehicle collision repair industry are associated with symptoms of neurotoxicity in spray painters and panel beaters (auto body repair workers). METHODS: Neurobehavioural symptoms were assessed using a cross-sectional study design in 370 vehicle collision repair and 211 reference workers using the EUROQUEST questionnaire. Full-shift airborne solvent levels were measured in a subset (n=92) of collision repair workers. RESULTS: Solvent exposures were higher in spray painters than in panel beaters, but levels were below current international exposure standards. Collision repair workers were more likely to report symptoms of neurotoxicity than reference workers with ORs of 2.0, 2.4 and 6.4 (all p

Surgical fires require an oxygen-enriched environment, a flammable substrate, and an ignition source. We hypothesized ambient oxygen concentration is proportional to the latency time to combustion and the incidence of surgical fires that are detected. We examined latency time and number of events, utilizing the VanCleave et al model of intraoral fire ignition under 60, 80, and 100% oxygen concentration and flow rates of 4 and 10 L/min. Results demonstrated that ambient oxygen concentration and flow rate correlated positively to the initiation of combustion. The number of combustion events with 60% oxygen was significantly lower than with both 80% (p = .0168) and 100% (p = .002). Likewise, the number of events with 80% oxygen was significantly lower than with 100% oxygen (p = .0019). Flow rate has a significant effect on the time to the first event (p = .0002), time to first audible pop (p = .0039), and time to first flash or fire (p < .0001). No combustion occurred at oxygen concentrations less than 60% or flows less than 4 L/min. We conclude that latency time to combustion is directly proportional to ambient oxygen concentration and flow rate. Minimum oxygen concentration and flow rate were identified in our model. Further research is indicated to determine the minimal clinical oxygen concentration and flow rate needed to support combustion of an intraoral fire in a patient.

ObjectivesWe have recently shown that solvent-exposed collision repair workers (spray painters and panel beaters) in New Zealand are at an increased risk of both self-reported and objectively assessed neurobehavioural effects, indicating a need for more effective exposure controls. This study assessed the association between personal protective equipment (PPE) use and workplace hygiene and symptoms of neurotoxicity in vehicle spray painters.MethodsExposure controls including PPE-use and workplace hygiene practices and symptoms of neurotoxicity were assessed in 267 vehicle repair spray painters. Symptoms were assessed using the EUROQUEST questionnaire.ResultsFrequent respirator and glove use was inversely associated with symptoms of neurotoxicity in a dose-dependent manner (p80%. Poor hygiene workplace practices, e.g. solvent exposure to multiple body parts were associated with an increased risk of symptoms, but this was not statistically significant. When using a general workplace hygiene score derived from a combination of PPE-use and (good) workplace hygiene an inverse dose-response trend was observed for reporting ≥5 (pConclusionsThis study has shown that PPE-use and good workplace hygiene are associated with a strongly reduced risk of symptoms of neurotoxicity in solvent-exposed vehicle spray painters. Glove use was most protective, suggesting dermal exposures may be of particular importance in the development of symptoms.

The hypothesis of this study is that small-handed female obstetrician-gynecologists (OB/GYNs) experience more physical stress while performing laparoscopic surgery compared to large-handed OB/GYNs. The size and grip and pinch strength of surgeon’s hands were measured and compared to the average size hands of females and males reported in the U.S. anthropometric literature databases on body dimensions. A descriptive questionnaire was administrated to six OB/GYN surgeons (five females and one male) to obtain general background information, including personal work experience and musculoskeletal disorders symptoms (MDSs). Operating room assessment using Rapid Upper Limb Assessment (RULA), a standard ergonomic assessment tool, and photographs/video that recorded body postures and motions of the surgeons was performed to identify risk factors of work-related MSDs. Primary findings from this study included: 1. Small-handed female OB/GYNs reported difficulty using laparoscopic instruments. 2. Small-handed female OB/GYNs experienced more physical stress according to RULA and questionnaire results while performing laparoscopic surgery compared to large- handed male and female OB/GYNs in this study. 3. Awkward postures tended to be more prevalent among smaller OB/GYNs as a function of surgical workstation layout and laparoscopic hand tools. Based on the observation, laparoscopic instruments need to be reengineered to help reduce the physical stress for small-handed surgeons.

Dust reduction equipment adapted for single-person operation was evaluated for gas-powered, commercially available cut-off saws during concrete curb cutting. Cutting was performed without dust control and with two individual exposure control methods: wet suppression and local exhaust ventilation (LEV). The wet suppression system comprised a two-nozzle spray system and a 13.3-L hand-pressurized water supply system with an optimum mean flow rate of 0.83 L/min for 16 min of cutting. The LEV system consisted of a spring-loaded guard, an 18.9-L collection bag, and a centrifugal fan with an estimated exhaust rate of 91 ft(3)/min. Task-based, personal filter samples were obtained for four saw operators during cutting durations of 4 to 16 min on five job sites. Seventeen filter samples were collected without dust control, 14 with wet suppression, and 12 with LEV, yielding a geometric mean respirable dust concentration of 16.4 mg/m(3), 3.60 mg/m(3), and 4.40 mg/m(3), respectively. A dust reduction of 78.0% for wet suppression and 73.2% for LEV was observed vs. no dust control. A statistically significant difference (p0.001) was also revealed for wet suppression and LEV when compared with no dust control; however, a significant difference (p = 0.09) was not observed between wet suppression and LEV. Despite these significant dust reductions, workers are still projected to exceed the ACGIH 8-hr time-weighted average threshold limit value for quartz (0.025 mg/m(3)) in less than 1 hr of cutting for both dust control methods. Further research is still needed to improve dust reduction and portability of both control methods, but the current LEV system offers important advantages, including a drier, less slippery work area and year-round functionality in cold weather.

In the wake of building information modelling, virtual reality is receiving attention for visualizing design details by means of virtual prototypes or virtual mock-ups. Examples for courthouse design review have prompted application to healthcare facilities. To facilitate perspective for patient-centred and evidence-based design, highly interactive, immersive virtual modelling is promoted to assist project stakeholders in validating design alternatives. This approach requires a significant database of model components to achieve timely turnaround of model concepts. The modelling of interactive elements (e.g. opening doors, folding beds) consumes more time than acceptable to the typical healthcare facility project team. The authors therefore are establishing a technology HUB to act as a central repository for object models shared by contributing partners. The HUB is intended to advance this approach and speed arrival to final product. The plan for this collaborative vehicle is described, as are issues rele...

For decades the literature has shown an association between work-related risk factors and back injuries among employees. However, only recently, there is a growing body of literature that suggests lifestyle risk factors may also be associated with back injuries. The purpose of this research was to determine if selected lifestyle risk factors are associated with a greater risk of back injuries. Further, there may be an association between job status and incident reporting, lost workdays cases and workers' compensation (WC) paid for back injuries among university employees. Aggregate data from a Health Risk Assessment (HRA) questionnaire were used to analyze 6053 university employees for lifestyle risk factors associated with back injuries. Of the total sample, 57% (n=3471) were female; 46% (n=2778) worked as clerical or service staff; and the mean age was 45years. Pearson chi-square (chi(2)) analyses indicate that job status (chi(2)=307.07, df=4, p.001) and gender (chi(2)=40.14, df=2, p.001) were associated with high risk back score. An ordinal regression analysis predicted that participants who exercised vigorously for at least 20min, 3 or more days per week, or 3 or more days per week of combined vigorous exercise and moderate-intensity physical activity are almost 30 times less likely to have a high back risk score compared to participants who do not exercise vigorously or participate in less than 3days per week of moderate-intensity physical activity (OR=29.68, 95% CI=25-35.25, p.001). Participants who have a low risk score for BMI are three times less likely (OR=3.20, 95% CI=2.74-3.75, p.001) to have a high back risk score when compared to participants who have a high risk score for BMI. A regression tree predicted high back risk scores were participants who: (1) receive an adequate amount of physical activity or vigorous exercise and is a male service or clerical staff; (2) do not receive an adequate amount of physical activity or vigorous exercise, and is not overweight; or (3) who do not receive an adequate amount of physical activity or vigorous exercise, and is overweight. Six years of Occupational Safety and Health Administration (OSHA) 300 logs and WC claims data paid for back injuries supported the finding that clerical or service staff had the greatest risk of back injuries. Based on the results of this study, there appears to be an association between lifestyle risk factors, job status and back injuries among university employees. We believe our evaluation approach may be used to study other work populations to verify the outcomes observed in this study.

This case study investigated the effectiveness of formal instruction of the Revised NIOSH Lifting Equation for university students who may use the equation in their future work. Their successes and challenges were examined through a class exercise and two exams, all of which followed the classroom instruction in applying the Lifting Equation. Results showed students (1) had difficulty determining relevant values for task variables from reading a job description, and (2) generally were able to calculate the Recommended Weight Limit (RWL) and Lifting Index (LI) when task variables were such that the associated multipliers were less than or equal to 1. However, when the multiplier was calculated to be greater than 1, students had difficulty interpreting the result. The task variable and multiplier (consistently the greatest challenge) were the asymmetry task variable, A, and the asymmetric multiplier, AM. Results indicate that the layout of the Job Analysis Worksheet for Step 1 may make it easy to make arithmetic errors when calculating multipliers. It is recommended that the worksheet be redesigned to help individuals decrease the probability of making an arithmetic error when calculating the task variables, multipliers, RWL, and LI. It is also recommended that the redesigned worksheet be tested to determine whether fewer arithmetic errors are made and if the worksheet is less confusing for an inexperienced user to use.

Background The authors conducted a study to determine the effectiveness of two waste anesthetic gas-scavenging systems. They also evaluated one of the systems to determine the effect of work practices in controlling waste nitrous oxide (N 2 O). Methods The authors collected a minimum of 13 data sets in each phase of the study that included infrared thermography, digital videography and real-time air analysis for ambient concentrations of waste N 2 O. Surgeon 1, who had experience using both systems, used the Safe Sedate Dental Mask (Airgas, Radnor, Pa.) system (system I) in phase I and the Porter Nitrous Oxide Sedation System (Porter Instruments, Hatfield, Pa.) (system II) in phase II. Surgeon 2, who did not have experience using system I, used it in phase III. To evaluate each system's effectiveness, the authors collected N 2 O air concentration data from phases I and II and compared the data with the National Institute for Occupational Safety and Health Recommended Exposure Limit (NIOSH REL). They also compared phases I and III to determine the effect of work practices on the systems' effectiveness. Results Surgeon 1 controlled occupational exposure to N 2 O significantly better using system I than using system II. Mean N 2 O air concentration levels during phases I and II were 61.6 parts per million (ppm) and 225.6 ppm, respectively. Surgeon 2 did not achieve results comparable to those of surgeon 1 in phase I using system I. Infrared thermography and air concentration data suggested that key work practices and patient and surgical variables accounted for the different results obtained in phases I and III. Conclusions Although neither system was able to control occupational exposure of N 2 O oxide below the NIOSH REL, system I met the American Conference of Governmental Industrial Hygienists threshold limit value of less than 50 ppm during an eight-hour day and performed significantly better than did system II. Clinical Implications System I achieved maximal efficiency when combined with consistent best work practices.

The goal of this project was to determine whether one type of earplug would allow a user to hear communication in a noisy environment better than two other types of earplugs. The three types of earplugs studied are newly available on the market. Sonomax SonoCustoms are custom fitted to the user. E-A-R Push-Ins are the newest form of foam earplugs, and Howard Leight SmartFits have an adaptable shape. One of the earplug manufacturers claimed to have improved verbal communications due to the design of the earplug. We hypothesized that the type of earplug providing better communication properties would have lower attenuation around the communication frequencies compared with the other types. To test this hypothesis, we used speech intelligibility and attenuation tests in the laboratory on 26 subjects, and real-time video exposure monitoring in the field (airport maintenance personnel) for visual communication cues. ANCOVA was used to analyze the data from the laboratory study. The type of earplug worn was not significant in the model (p-value 0.0849), nor was attenuation of the earplug (p-value 0.2379). Further analysis showed that attenuation did not differ significantly among earplugs (p-value 0.5903). Logistic regression was used to analyze the data from the field study. Again, the type of earplug was not significant in the model (p-value 0.0965). A comfort questionnaire determined that Howard Leight SmartFits and the E-A-R Push-Ins were more comfortable and easier to use than the Sonomax HPDs (p-value0.0001). We found a definite difference between manufacturers' attenuation data and our attenuation data, especially in the frequencies for 125-1000 Hz. Also, there was no difference in frequency and overall attenuation among the HPDs. This resulted in no difference in communication abilities among the types of HPDs.

The threat of bioterrorism and pandemics has highlighted the urgency for rapid and reliable bioaerosol detection in different environments. Safeguarding against such threats requires continuous sampling of the ambient air for pathogen detection. In this study we investigated the efficacy of the Airborne Sample Analysis Platform (ASAP) 2800 bioaerosol sampler to collect representative samples of air and identify specific viruses suspended as bioaerosols. To test this concept, we aerosolized an innocuous replication-defective bovine adenovirus serotype 3 (BAdV3) in a controlled laboratory environment. The ASAP efficiently trapped the surrogate virus at 5 × 10(3) plaque-forming units (p.f.u.) [2 × 10(5) genome copy equivalent] concentrations or more resulting in the successful detection of the virus using quantitative PCR. These results support the further development of ASAP for bioaerosol pathogen detection.

This project incorporates radiation survey training into a real-time video radiation detection system, thus providing a practical perspective for the radiation worker on efficient performance of radiation surveys. Regular surveys to evaluate radiation levels are necessary not only to recognize potential radiological hazards but also to keep the radiation exposure as low as reasonably achievable. By developing and implementing an instructional learning system using a real-time radiation survey training video showing specific categorization of work elements, radiation workers trained with this system demonstrated better radiation survey practice.

Locomotor behavior at the roofing worksite is challenged by factors such as sloped surfaces, wind gusts and handling loads. Chronic exposure to this environment may result in enhanced locomotor strategies that are resistant to aging effects. The purpose of this study was to determine if roofers demonstrated enhanced locomotor strategies and if the strategies were maintained with age.The gait of ten younger roofers (mean age 27.2 years), eight older roofers (55.4 years), ten younger controls (25.4 years) and nine older controls (57.6 years) was examined during level gait and stepping up onto a wooden surface (0.15m high). Subjects either carried no load, an empty box or the same box loaded to the equivalent of 5% body mass.Work by age interactions were observed for toe clearance, step width, net angular momentum of the head, arms and trunk segment and gait speed (P0.0001). Younger roofers demonstrated the greatest toe clearance; older roofers had a smaller lead clearance but decreased variability. Older control groups had the greatest risk of tripping due to low lead toe clearance and high variability, and were least likely to recover if they did trip due to faster gait speed and increased net angular momentum. Work experience resulted in enhanced changes in lead toe clearance and mitigated age-related changes in step width and net angular momentum.Challenging environments show promise for maintaining balance skills in older adults; however care should be taken when introducing inexperienced older adults to a challenging environment.

Nursing assistants (NAs) who work in nursing and personal care facilities are twice and five times more likely, respectively, to suffer a musculoskeletal disorder compared to service industries and other health care facilities, respectively. The purpose of this study was to develop an ergonomics training program for selected NAs at a state-run veterans' home to decrease musculoskeletal disorders by 1) developing questionnaires to assess musculoskeletal stress, 2) evaluating the work environment, 3) developing and using a training package, and 4) determining the application of the information from the training package by NAs on the floor. Results show two new risk factors not previously identified for nursing personnel in the peer-reviewed literature. Quizzes given to the nursing personnel before and after training indicated a significant improvement in understanding the principles of ergonomics and patient-handling techniques. Statistical analysis comparing the pre-training and post-training questionnaires indicated no significant decrease in musculoskeletal risk factors and no significant reduction in pain or discomfort or overall mental or physical health.

In this study, a mechanical model was applied in order to replicate potential surgical fire conditions in an oxygen-enriched environment with and without high-volume suction typical for dental surgical applications. During 41 trials, 3 combustion events were measured: an audible pop, a visible flash of light, and full ignition. In at least 11 of 21 trials without suction, all 3 conditions were observed, sometimes with an extent of fire that required early termination of the experimental trial. By contrast, in 18 of 20 with-suction trials, ignition did not occur at all, and in the 2 cases where ignition did occur, the fire was qualitatively a much smaller, candle-like flame. Statistically comparing these 3 combustion events in the no-suction versus with-suction trials, ignition (P = .0005), audible pop (P = .0211), and flash (P = .0092) were all significantly more likely in the no-suction condition. These results suggest a possible significant and new element to be added to existing surgical fire safety protocols toward making surgical fires the “never-events” they should be.

As one enters the city of Bath, Maine, and approach the gates of Bath Iron Works (BIW) a sign proclaims, “Through These Gates Pass the Best Shipbuilders in the World.” These words are a way of life...

Control of occupational exposures to hazardous chemical and physical agents costs industry more than 150 billion dollars per year. Development of a method to identify and control hazardous agents is a high priority for industry. The application of this method will save industry millions of dollars by pinpointing sources of exposure and enable them to invest in more cost/effective engineering and ergonomic solutions. The use of real-time instruments to measure and control hazardous agents is not new. However, the application of ergonomic principles and videographic techniques to link hazardous exposures to employee job functions is new. Such methods are particularly useful when the hazardous agents are highly toxic, have low regulatory limits (i.e., permissible exposure limits), and where changes in work organization and employee work practices can significantly increase or decrease exposure to such agents. This paper discusses how a system developed at Purdue University uses real-time instruments combined with videography to evaluate and control hazardous chemical and physical agents in the occupational environment.

Few studies have addressed waste anesthetic gases (WAGs) in the postanesthesia care unit (PACU) related to exhaled sevoflurane and nitrous oxide.To evaluate the effectiveness of a new scavenging system to control WAGs in the PACU.Comparative and descriptive study.This pilot study compared exposure to WAGs with and without a scavenging system using infrared technology to visualize and quantify exposure to these gases in the PACU.The results showed a significant reduction (P.05) in both nitrous oxide and sevoflurane at both six inches and three feet from the patient's breathing zone, as well as in the work area of the perianesthesia nurses in the PACU.WAG exposure may be more easily managed through the use of this new scavenging system to better control occupational exposures to these gases among PACU personnel.

Occupational exposure assessment is one branch of exposure assessment and addresses the exposure problems that occur in the workplace. Through exposure assessment, we generally describe and identify the nature and size of the various populations exposed to hazards, the magnitude and duration of the exposures, and the causal factors of exposure. The present study explores the strategy for occupational video exposure monitoring includes video data in the assessment process and aims to establish an association between exposure levels and workplace events and to identify the causal factors. The case studies represent the progression in the development of real-time monitoring of exposure to different types of hazardous materials. Further the current application and development of each part of the assessment system and new ideas for improvement of the VEM system are suggested. Keywords: video exposure monitoring (VEM); short-term exposure limit (STEL) exposure; MTVA software; thermoluminescent dosimeters (TLDs)

Full scale physical mock-ups of specific hospital units such as patient rooms are routinely utilized to serve the multiple purposes of constructors, designers, and owner stakeholders for healthcare facility projects. The shortcoming with this practice is that the mock-up is constructed during the construction phase and is of limited use for making extensive decisions regarding the functionality of the room design. Three-dimensional visualisation tools offer healthcare facility stakeholders the opportunity to comprehend proposed designs more clearly during the planning and design phases, thus enabling the greatest influence on design decision making. While several options exist, based on their experience with a bariatric patient room model, the authors promote the utilization of Virtual Reality mock-ups for design review because of their enhanced capacity for an immersive, interactive experience with the design and for the long-term utility of such models for the balance of the project life cycle.

In this paper the authors present a pathogenic mechanism of carpal tunnel syndrome (CTS) and a heuristic conceptual model to assess the musculoskeletal stress of manual work for the purpose of establishing quantitative guidelines to prevent work-related CTS. The model is based on the concept that the frictional energy of manual work within the wrist initiates local tenosynovitis as and CTS, the value of the product should not exceed a limit derived from the population-based threshold. Reliable, validated techniques should be used for gathering data on the stress factors of manual work for the purpose of establishing quantative guidelines to control and prevent work-related CTS.

Cumulative trauma illness currently accounts for over half of all occupational illness in the United States. From 1987 to 1989 there was a 100% increase in the reported number of cases of cumulative trauma illness (Bureau of Labor Statistics 1990). Shoulder region pain ranks second only to low back and neck pain in clinical frequency, and the occurrence of occupational shoulder illness is on the rise. This paper summarizes findings of a subset of recent epidemiologic, laboratory, and field studies conducted in order to identify occupational risk factors for cumulative trauma disorders (CTDs) of the shoulder region. These studies have identified the following risk factors as being associated with particular shoulder pain syndromes: awkward or static postures, heavy work, direct load bearing, repetitive arm movements, working with hands above shoulder height, and lack of rest. The paper begins with a discussion of several shoulder disorders, includes problems in studying cumulative trauma, presents results of recent studies, and concludes with suggested ergonomic controls that could help to reduce the incidence of shoulder disorders, by eliminating or reducing exposure to the associated risk factors.

Changes in heart rate variability (HRV) have been linked with cardiac disease and death. Exposure to particulate matter from various sources such as tobacco smoke has been shown to cause alterations in HRV. This study investigated the effects of occupational exposure to environmental tobacco smoke (ETS) on HRV. Air monitoring was conducted in three bars in which smoking was permitted and one bar where smoking was not permitted. Pre- and post-work shift heart rate monitoring was conducted on volunteer staff from the establishments. Heart rate variability parameters, including SDNN and RMSSD, were calculated, and the differences between pre- and post-shift values were plotted and analyzed with respect to ETS exposure. Post-shift minus pre-shift values of SDNN and RMSSD significantly decreased with exposure to ETS (p

Generation of muscle strength is a complex procedure of myofilament activation, nervous feedforward and feedback control, and use of mechanical leverages within the human body. Since strength measurement directly at the muscle is (currently) not feasible, it is usually done at the outside of the body, at the interface with some kind of a dynamometer. This poses various challenges because of difficult mechanical and physiological modelling of the conditions, and because of difficulties in experimental control. To better understand and measure human motor performance, a model of muscle functions and control is discussed, and means for computer-aided position and motion observation are proposed. Experimental variables are classified, and a taxonomy for static (isometric) and several dynamic measurement techniques is described.

Noise in open-plan computer rooms and annoyance associated with it was reported to be a problem in a large service organization. An experimental investigation was undertaken to determine noise levels in this organization's computer rooms. The noise spectrum was found to be similar in all facilities investigated but substantially different from those of open-plan offices. Fifty percent of all respondents rated the noise level (on a 25–point scale) between extremely annoying and unbearable and intolerable; 10% of the respondents considered the noise very annoying; 20% of the respondents considered the noise levels moderately annoying; the remaining respondents did not seem to have a major problem. Conversational sound and computer-printer beeping sounds were reported to be most annoying by 90% of the respondents who considered the noise levels annoying.

The objective of this research was to evaluate the effectiveness and provide a limited economic evaluation of an office ergonomics program at a major university from 1995 to 2007. The relationship between office-related recordable injuries, reported lost time, severity of these injuries, and the Workers' Compensation (WC) paid was analyzed and the corresponding incident cost was calculated. Two major datasets analyzed were OSHA 200/300 logs (1991-2007) and WC claims paid (1999-2007). Since the beginning of the office ergonomics program in 1995 and through 2007 (13-year period), the number of office cumulative trauma disorder (CTD) cases decreased by 53%. Since the official start (in 1999) of a 50-50 cost share agreement for office equipment purchases between the university's Safety and Health Department (SHD) and the university departments evaluated, it was observed that the incident rate decreased by 63%, Total Days Away/restrict or Transfer (DART) rate decreased by 41%, Lost Time Case (LTC) rate decreased by 71% and office-related carpal tunnel syndrome decreased by almost 50%. The long-term goal of this research is to demonstrate the self-sustainability of an office ergonomics program by showing that equipment costs are eventually offset by a decrease in WC claims paid and lost time from office-related injuries and illnesses. While limited, this research helps in cost-justifying the implementation of future office ergonomics programs for large organizations.

It has been 20 years since video exposure monitoring (VEM) was embraced as an instrument to provide better documentation of at-risk workers both in Europe and in the United States. Although the first VEM efforts started independently, the passion for this new technology and what it can do to improve the occupational environment has been advanced by a small but growing team of researchers on both sides of the Atlantic. As technology advances over the next ten years, VEM is set to become one of the major instruments in the arsenal of occupational exposure assessment and control. The technical aspects and uses of VEM are reviewed in this issue by some of the key players in these developments (Rosen et al., 2005). In the 1980s a small group of researchers from the engineering control technology branch of the National Institute for Occupational Safety and Health (NIOSH) were working on developing controls to reduce worker exposure to airborne chemicals during batch processing at a manufacturing plant in the Midwest. The research team consisted of a chemical engineer and two occupational hygienists, one specializing in the use of real-time instruments and the other in ergonomics. The diverse talents and skill sets of this team formed a synergy that took advantage of emerging technologies in the portable computer, video and realtime sensor markets (McGlothlin et al., 1987; 1996). The result of the application of this new technology, VEM in the United States was very promising. For the first time, researchers could discern exposure sources and the interaction between work practices and engineering controls such as local exhaust ventilation. Pinpointing exposure sources led to cost effective controls and the development of an effective feedback mechanism for showing workers and management where they had exposures and where they could be controlled. Overlaying videography with the real-time particulate sensors proved very effective. At the same time, unknown to the NIOSH researchers, a like-minded group of researchers at the National Board of Occupational Safety and Health in Sweden (now called the National Institute for Working Life) were considering ways to engage exposed workers in environmental control processes (Rosen and Lundstrom, 1987). The goal of this group was to develop methods for workers to see with their own eyes the potential hazards (in real-time) to which they were being exposed. Computer and video technology were getting less expensive and more portable, and real-time instruments (in the United States the instrument was the handheld aerosol monitor or HAM) were being used for particulate monitoring. By visualizing the work being done and combining it with real-time monitoring, occupational hygienists had a formula for success. They could provide a convenient means of feedback for workers and management and they had a new weapon to ‘see’ exposure sources and targeting controls. As the benefits of this new occupational exposure assessment method became obvious, other NIOSH researchers applied this method to their projects, resulting in a popular NIOSH government publication titled ‘Analyzing workplace exposure using direct reading instruments and video exposure monitoring techniques’, (CDC/NIOSH, 1992). Researchers for the National Institute for Working Life in Sweden identified two methodologies to evaluate worker exposure to air contaminants, one of which was commercialized (Walsh, 2002). From 1980 through the 1990s NIOSH researchers explored different ways to use this technology. They concluded that while the technology was unique, it would primarily be used to *Tel: +1 765 469 6359; fax: +1 765 496 1377; e-mail: jdm3@purdue.edu

Nursing assistants (NAs) who work in nursing and personal care facilities are twice and five times more likely, respectively, to suffer a musculoskeletal disorder compared to service industries and other health care facilities, respectively. The purpose of this study was to develop an ergonomics training program for selected NAs at a state-run veterans' home to decrease musculoskeletal disorders by 1) developing questionnaires to assess musculoskeletal stress, 2) evaluating the work environment, 3) developing and using a training package, and 4) determining the application of the information from the training package by NAs on the floor. Results show two new risk factors not previously identified for nursing personnel in the peer-reviewed literature. Quizzes given to the nursing personnel before and after training indicated a significant improvement in understanding the principles of ergonomics and patient-handling techniques. Statistical analysis comparing the pre-training and post-training questionnaires indicated no significant decrease in musculoskeletal risk factors and no significant reduction in pain or discomfort or overall mental or physical health.

In this study, proactive stability control while handling loads and negotiating an elevated surface was examined. Ten young healthy males completed two gait-mode conditions--level walking and negotiating a raised surface. Load-handling conditions were: no load, empty box (reduced visual information), and loaded box (reduced visual information combined with increased inertial load). The lower limb trajectory in the sagittal plane was not modified as a function of reduced visual information or increased inertial load. The step width decreased while stepping over the surface and carrying the loaded box. The trunk pitch angle was biased backwards for both the empty box and the loaded box. When carrying the empty box and negotiating the surface, the trunk pitch range of motion (ROM) increased which may have been a strategy to increase visual exteroceptive information. As increased net trunk pitch could destabilize the system, concurrent stabilizing strategies--decreased gait velocity and reduced net trunk roll velocity--were observed. To meet the equilibrium goals when carrying the loaded box, the trunk pitch ROM and net pitch velocity were reduced during both level walking and surface accommodation. Trunk roll ROM was reduced when carrying the load and negotiating the surface. This study extends our knowledge regarding whole body coordination strategies during anticipatory locomotor adaptations.

A review is given of National Institute for Occupational Safety and Health (NIOSH) efforts to control N2O at a pediatric dental operatory from 1978 to the present. Measurements of N2O concentrations were made on four occasions before and after installation of different controls, using an infrared analyzer. Air velocity and volumetric flow measurements also were taken, Video imaging was done in some cases simultaneously with real-time N2O measurements to correlate work practices with exposure data. An infrared imaging system was used to identify sources of N2O. Critical components of resulting recommendations for control include monitoring of N2O concentrations; use of engineering controls, such as a scavenging mask, an effective dilution ventilation system, and auxiliary exhaust; good work practices; maintenance of the equipment; and worker education. Data presented strongly supports the hypothesis that better implementation of controls leads to reduction of N2O exposures. N2O concentrations were reduced by a factor of 61 from their initial levels. The current NIOSH recommended exposure limit of 25 ppm TWA during the time of N2O administration appears to be achievable.

Sanderson, L.M., Collins, J.W. and McGlothlin, J.D., 1986. Robot-related fatality involving a U.S. manufacturing plant employee: Case report and recommendations. Journal of Occupational Accidents, 8: 13–23. This article presents the salient characteristics of the first publicly documented robot-related fatality in the United States and summarizes recommendations for both preventing similar accidents and directing future robotic safety research and practice. In July of 1984, a 34-year-old die cast operator with 15 years experience was pinned between the right rear end of a hydraulic robot and a “safety pole”. This operator was one of approximately 66 operators employed by the die cast company and was considered by many to be among the most adept at working with the plant's two robots. The major factor contributing to the death of this worker may have been his own behavior; he had been formally trained and instructed not to enter the envelope while the robot was operational. This American fatality has several characteristics in common with reported Japanese robot fatalities. These characteristics include: experience, entering the robot range of motion with power on, overriding existing safety systems, being struck from behind, and being pinned or crushed at a pinch point between the robot and stationary equipment. Recommendations for prevention of such injuries are made according to broad categories pertaining to ergonomics, training, and supervision. Specific recommendations for future robotic safety research and practice include improving information dissemination and consultation, addressing psychological factors of workers interacting with robots, assessing the effectiveness and limitations of safeguarding, establishing uniform and objective criteria for training and possibly certification, and expanding scientific research to include better surveillance and epidemiologic and ergonomic studies.

In responding to a request for technical assistance, the National Institute for Occupational Safety and Health developed a method for sampling and analysis of iodine. Atmospheric iodine was collected on a solid sorbent tube and analyzed by ion chromatography. Overall recovery of iodine from the impregnated charcoal was 101% with 9.6% relative standard deviation. Iodine concentrations in field samples collected at a graphic plate processing plant ranged from 0.002 ppm to 0.15 ppm.

Past studies have shown that ventilation does not always provide complete dust control during the manual weigh-out and transfer of powders. However, these studies have not shown where the dust emission sources are located. A field study was conducted in a plastics manufacturing plant to evaluate factors affecting worker dust exposure at a ventilated booth which was used for the weigh-out and transfer of powdered materials. A unique study plan was formulated utilizing real-time air sampling and short-term air sampling in conjunction with an ergonomic evaluation to determine activities or factors associated with dust exposure. The factors and activities evaluated were depth of scooping, cleanliness of the workers' clothing, worker anthropometry, and work practices. Realtime air sampling and work cycle evaluation showed that dust concentrations were highest when the worker was scooping material out of the drum, and these levels increased dramatically when the worker placed his breathing zone inside ...