We summarise more than 40 years of Liberty Mutual psychophysical research on lifting, lowering, pushing, pulling and carrying, including the 7 studies used to develop the 1991 Liberty Mutual Tables and 12 subsequent studies. Predictive equations were developed based on 612 mean maximum acceptable loads (MALs), representing 388 unique conditions from 123 female and 149 male participants, starting with a maximum reference load that is scaled based on frequency, height, distance (vertical for lift & lower, horizontal for push, pull and carry tasks) and horizontal reach (for lift & lower tasks). Representative coefficients of variation are provided to allow for the calculation of MALs for any percentile. Each equation performed well and, overall, they explained 90% of the variance in MAL values, with RMS differences of 6.7% and 4.8% of the full range for females and males, respectively. We propose that these equations replace the 1991 Liberty Mutual Tables. Practitioner summary: We propose predictive equations to replace the 14 manual materials handling tables in Snook and Ciriello (1991). These equations are based on 12 more publications, matched the empirical data well, are easier to use and allow for both a wider range and more specific inputs than the tables.

Wellness is about the person and decisions they make about their health, safety and well-being both on and off the job. However, conflicts can arise in the occupational (health protection) and non-occupational (health promotion) side of the wellness. For example, positive steps can be made in off-site wellness but if the design of jobs, tasks, equipment and the organization do not to match the capability and limitations of the worker then we have a wellness conflict. This paper will begin with an overview of wellness including the dimensions of wellness and impact on workers compensation claims frequency and costs. Integrated approaches to wellness will be described and an evidence-based integrated wellness continuum will be introduced. This wellness continuum will highlight specific safety and ergonomic interventions critical to the success of occupational wellness initiatives. Finally, an Integrated Health and Wellness roadmap will be provided offering guidelines for implementing health promotion and health protection interventions.

The aging workforce, increase in obesity, and lack of exercise and physical activity are changing the landscape of work environments in the industrialized world. The goal of this panel is to make ergonomics and safety professionals aware of the importance of examining health and wellness issues, aging, obesity, and other modifiable health risks pertaining to occupational health. The first of seven presentations will cover an evidence based wellness continuum that describes specific factors that can motivate healthy work environments. The second presentation discusses the challenges and implications of the aging workforce with emphasis on the role of ergonomics in maintaining health, wellness and working contributions of the aging workforce. In general, muscle mass and muscle strength decrease with age, however the third presentation examines if such age-associated changes are evident during one-handed isometric pulling. Stratifying injury risk in overweight and obese populations is still a challenging endeavor. The fourth presentation demonstrates the biomechanical consequences of gait (a)symmetry due to being overweight and the risk of falling. There is an increasing evidence of obesity influencing every organ system adversely in the human body, including the brain. The fifth presentation examines the association between work performance of obese and non-obese individuals during incremental repetitive lifting and change in their cerebral hemodynamics and cardiorespiratory responses. An interaction between aging and obesity in addressing the risk for involvement in a motor vehicle crash is discussed in the sixth presentation. The final presentation focuses on understanding the integrated efforts of physiological systems such as respiratory, cardiovascular, and skeletal muscle within the context of aging, obesity and physical activity.

Although one-handed pulling is commonly used in many tasks, normative data on the populational strength capacity are scarce. A strength test protocol was administered to collect data on static one-handed pulling strength using four handle heights and three pulling directions: across (handle opposite to the pulling hand), front, and side (handle on the same side of the pulling hand). Eighty-six participants (46 men and 40 women) in five age groups completed the protocol. The results showed that pulling from the side of the body resulted in the greatest strength, followed by front and across pulls. As the handle height increased from 61 cm above the floor, to above the shoulder, the pulling strength decreased. This dataset provides occupational safety and ergonomics professionals gender specific normative data on one-handed pull strength capacity in different age groups.

Bilateral manual materials handling tasks, such as lifting, pushing, and pulling, have been well studied in their physiological, biomechanical, psychophysical, and epidemiological aspects. Although this form of exertion is common in many industries and tasks, the basic capacity of one-handed pulling tasks is not well known. A strength test protocol was administered to collect isometric one-handed pulling strength at four handle heights and three pulling directions. Twenty-six male participants in five age groups showed that pulling from the side of the body resulted in the greatest strength. As the handle height increased from 61 cm above the floor to above the shoulder, the pulling strength decreased. This dataset lends occupational safety and ergonomics professionals the knowledge of the strength capacity of a population similar to our study sample.

The study of slips and falls has traditionally focused on body kinematics and tribology. However, this strictly mechanical approach does not allow scientists to assess the importance of each component in relation to the complete system, and thus it lacks integration. The purpose of this chapter is to present and demonstrate the components of a broad analysis for in-depth understanding of slips and falls while walking on level surfaces. In most slip-and-fall studies, balance analysis is simplified and attributed to the point of heel contact. To determine sufficient fall prevention strategies, however, one must analyze balance before the critical moment of lost control. Such an approach requires the sciences of biomechanics, mechanics, anatomy, and neuromuscular control, as well as tribology. Causes of slips and falls are complex, and prevention approaches are often reactive, driven by high-injury trends and lawsuits. Prevention strategies need to be more proactive: Understanding the causes of accidents can help in identifying and correcting hazards before they cause problems. Examples include reporting incidents, selecting the right flooring, selecting footwear, and implementing proper floor-cleaning procedures. A combined effort among all members of the organization, including communication across the entire work system, is critical to the success of slip-and-fall prevention efforts.

A survey of Certified Professional Ergonomists (CPEs) was conducted to gather information on the types of basic tools, direct and observational measurement techniques, and software used by practitioners. The motivation for the survey was to better understand what types of tools and methods practitioners use, their opinions of these tools, and to potentially gain an understanding of the constraints or preferences that influence this selection. Reasons for using or not using a selection of tools were also surveyed. Of 578 surveys that were delivered to CPEs and Associate Ergonomics Professionals, 308 were returned for a response rate of 53%. The respondents tended to be biased towards physical ergonomics, as the survey primarily focused on this area of ergonomics. A high percentage of respondents reported using tape measures, video cameras, stopwatches and digital cameras. The most commonly used observational methods were those involving manual materials handling, whereas the most commonly used direct measurement tools were pinch and grip dynamometers and push/pull gauges. The frequency and type of checklists, software, and anthropometric data used are summarized.

MANUAL MATERIALS HANDLING (MMH) tasks (pushing, pulling, lifting, lowering and carrying) are the leading source of workers’ compensation claims (Dempsey and Hashemi). MMH remains a common exposure in many industry sectors including manufacturing and service occupations. The most effective means of minimizing risk is through the application of engineering controls—either removing the exposure through automation or reducing it through ergonomic design or mechanization. The specific tasks, machines and/or equipment to be modified are often selected based on the results of a detailed ergonomic analysis. Fewer workers now perform a single task or a few tasks repetitively, as many of these jobs have been automated. As a result, the SH&E professional must assess a wide range of tasks required by a job, particularly in the service industry where jobs are characterized by variable demands. Although both types of jobs require frequent, repetitive handling, the latter is characterized by more variability in task parameters such as load and lift distance. Ergonomic assessments of these jobs provide valuable information for job design and redesign decisions. Physical loading posed by MMH is assessed using different design criteria, such as spinal compression (biomechanical approach), oxygen consumption (physiological approach) and the percentage of the population that finds a task acceptable with respect to fatigue and stress (psychophysical approach). Manual handling criteria are usually applied through observational methods. The analyst first separates a job into distinct tasks, then measures the parameters of the tasks. The parameters are then used to estimate stress posed by the tasks. Many of these methods can be applied using a tape measure, protractor and watch. Examples of parameters measured include joint angles, task frequency, lift distance and object weight. Video analysis is helpful or required for some analyses, particularly for biomechanical assessments. Before job design and redesign decisions are implemented, an understanding of MMH risk factors and acceptable workloads is recommended. Risk factors associated with lifting, lowering, pushing, pulling and carrying tasks or associated with the work environment include: •excessive weights and forces; •undesirable postures such as bending, reaching and twisting; •slips and falls due to environmental hazards while handling materials; •prolonged sitting; •whole-body vibration. Selection of a particular analytical method is driven by the SH&E professional’s preference and by which method is most appropriate. For lifting and lowering tasks, Figure 1 shows a graphical representation of the influence of task frequency on the choice of tool, where darker shading indicates higher relevance. This was derived from work based on a comprehensive review of the literature (Dempsey). Biomechanics is best for analyzing high-load, low-frequency exposures, whereas the physiologic approach is intended for high-frequency tasks. Psychophysics is best for intermediate frequencies. Additionally, the most important practical aspects of selecting a method, such as expertise and cost, are shown in Table 1. Of the methods listed in Table 1, the psychophysical approach is applicable to the widest range of tasks, in part because of the large databases available. Psychophysical tables are among the easiest MMH assessment methods to use, and the tables published by Snook and Ciriello are the most comprehensive in terms of the range of task parameters covered, types of tasks (lifting, lowering, pushing, pulling and carrying) and the number of subjects used to develop the database (Snook and Ciriello; see Mital, et al for additional tables). Patrick G. Dempsey, Ph.D., CPE, is director of experimental programs at the Liberty Mutual Research Institute for Safety in Hopkinton, MA. After receiving a B.S. in Industrial Engineering from the State University of New York at Buffalo, he completed his M.S. and Ph.D. degrees in Industrial Engineering at Texas Tech University. Dempsey serves on the editorial board of the International Journal of Industrial Ergonomics and is a scientific editor for Applied Ergonomics. He is a member of the American Society of Biomechanics, Ergonomics Society, and Human Factors and Ergonomics Society, as well as a senior member of the Institute for Industrial Engineers.

A survey of Certified Professional Ergonomists (CPEs) was conducted to gather information on the types of basic tools, direct and observational measurement techniques, and software used by practitioners. The results of the industrial ergonomics tools are reported here. A high percentage of respondents reported using tape measures, video cameras, stopwatches and digital cameras. The most commonly used observational methods were those involving manual materials handling, whereas the most commonly used direct measurement tools were pinch and grip dynamometers and push/pull gauges. The type of checklists, software, and anthropometric data used also are summarized, and potential reasons for use, or lack of, are discussed.

Advances in information technology are allowing selective employees to work “anywhere” and at “anytime.” The work location for some employees is changing from the traditional corporate office to a virtual work location, such as the home, hotel, airport, shared and satellite office, client office and the car. This trend toward “alternative work styles” and the distributed workforce is likely to continue. As these work styles and virtual workplaces continue to emerge, understanding and designing effective work systems using a macroergonomics perspective is essential to achieve the benefits of distributed work and telecommuting. In this paper, we will provide an overview of the major macroergonomics issues associated with telecommuting. First, we present the literature databases used for this paper, a macroergonomics perspective and model. Next, examples of telecommuting programs, including the organizational structure, implementation process and evaluation strategy are given. A review of the existing empirical research concerning telecommuting and its implications are also discussed. Further, a macroergonomics process for managing the health and safety of telecommuters is described. In summary, a discussion of future telecommuting research and program development using a macroergonomics, work system design approach, is given.

The preliminary results of a prospective epidemiological study of the revised NIOSH lifting equation are presented. The baseline evaluations included assessment of lifting and lowering tasks with the revised NIOSH equation, as well as a questionnaire regarding personal variables. Subject follow-up was primarily accomplished through postal questionnaires, telephone interviews, and surveillance for workers' compensation claims for low-back disorders. The preliminary results reported are based on approximately 375 person-years of exposure; however, the follow-up period is still in progress. Important findings related to the usability of the revised NIOSH equation across several types of common exposures are also discussed.