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The U.S. manufacturing industry constitutes 8.3% of the workforce, but experiences a higher percentage of workplace injuries (12.6%) and workplace fatalities (7.3%) (BLS, 2016). Manufacturing environments are often characterized by dynamic resources including interactions between mobile equipment and pedestrian workers. The hazardous work environment characteristic of manufacturing facilities is evident in the high ratios of workplace injuries and fatalities compared to other industrial sectors in the U.S. A common problem in this environment is struck-by incidents between forklifts and employees completing tasks on the ground surface (BLS, 2016).
Opportunity exists to decrease the number of injuries, illnesses and fatalities in manufacturing work environments. The authors identified a need to evaluate the capabilities of magnetic field sensing technology to alert manufacturing personnel when hazardous situations exists.
This article reviews an experimental evaluation of the effectiveness of magnetic field proximity-sensing technology deployed in an active indoor manufacturing environment. A test bed and experimental trials were created to assess the effectiveness of a select proximity-sensing system. The research scope involves hazardous proximity situations and conditions between forklifts and pedestrian workers in a manufacturing environments.
Experiments were created to assess multiple variables associated with the successful implementation and operation of magnetic field proximity sensors on a forklift and pedestrian workers in an active manufacturing facility. Metrics were used to evaluate the technology’s effectiveness, including alert range, alert strategy, power source, cost and system complexity. Human-equipment interaction scenarios were created to assess the technology’s effectiveness.
Throughout history building codes have been a means to protect people and property. History provides many examples of catastrophic losses of life and property attributable in part to building codes or lack thereof.
New York City (NYC) offers a classic example of how important building codes are in protecting residents’ safety and health. Regulation of construction operations is an aspect of building codes that is crucial in densely populated areas. NYC residents face increased risks of death or serious injury due to construction operations in areas with high population density, vertical high-rise construction, zero lot line construction and proximity to operations that require heavy materials and equipment.
In response to multiple high-profile incidents, city officials added a code requiring major construction projects to have an approved site safety plan and licensed site safety manager on site during operations. OSH literature supports this approach to increasing safety and health.
To the author’s knowledge, no other jurisdiction worldwide through its building code licenses site safety managers and requires their presence on site during construction operations. The city’s requirements are progressive and urban areas could improve safety and health by enacting similar requirements via their respective building codes.
Codes Borne Out of Disaster
Throughout history, communities have used codes and rules related to buildings to increase the population’s safety and health. For example, the Code of Hammurabi (circa 1772 B.C.) stated that if a builder constructs a house improperly and it collapses and kills the owner, then the builder should be put to death (Gross, 1996).
Competing views exist on the requirements for how and when to control potentially hazardous energy. On one hand is OSHA’s 29 CFR 1910.147 standard, promulgated in 1989. On the other hand is ANSI/ASSE Z244.1-2016, a voluntary consensus safety standard written by industry stakeholders to address the control of potentially hazardous energy. Although the common goal of both standards is to protect workers from harm, some conflicts arise over how to achieve this goal. Furthermore, significant differences between the requirements in these documents have created confusion as to how to best control hazardous energy to protect employees.
This article, excerpted from The Battle for the Control of Hazardous Energy (Main & Grund, 2016), reviews the history of these standards to help safety professionals understand and appreciate the changes that have occurred over time; explains why the requirements are the way they are; and explores why conflict exists over the interpretation and application of the standards. Understanding the history and developments will help OSH professionals implement effective hazardous energy control solutions.
Why Does This Matter?
An employer has a legal right to contest any citation it receives from OSHA if the employer believes it did not violate a standard. In this regard, understanding the history of the standard can help an employer understand why certain solutions are prohibited under OSHA; support its effort to contest and defend against an OSHA citation(s); and, more fundamentally, apply the current standards to prevent harm in the workplace.
Fossil fuel power generation operations harbor many various occupational health hazards. These chemical, biological and physical hazards range from the routine to the rare. This article discusses the importance of anticipating and characterizing all occupational health hazards, and illustrates a sampling of these hazards. In reviewing these examples, remember two key points: 1) hazards, exposures and controls will vary significantly from one site to another; and 2) exposures may be adequately managed through appropriate controls.
Anticipating Workplace Health Hazards in the Power Industry
The risk faced by power industry employees is a function of the hazards present and the exposure level to those hazards. An organized, systematic method of exposure and risk assessment is key to controlling these risks through a successful, effective occupational health and industrial hygiene program. The use of this systematic method, known as qualitative exposure assessment (QEA), to characterize workplace exposures to chemical, physical and biological agents is the solid foundation of this process (Figure 1, p. 50).
Initial qualitative exposure assessments typically involve a site visit by an industrial hygienist who will interview personnel and examine work areas for hazards, controls, work activities and chemicals. This initial assessment represents a snapshot in time; it is performed within a limited time frame and depends heavily on information provided by employees, limited observations, and the assessor’s skills and experience. Thus, this initial assessment tends to be somewhat limited in its comprehensiveness.
Complicating matters, after completion of the initial assessment, operations, materials, equipment and conditions are ever-evolving and highly subject to change. To ensure a sustainable hazard control program, a continuous improvement cycle must be woven into the QEA process.
The downward trend of electrical fatalities is a reflection of several factors: ongoing replacement of ignitable materials in electric arc protective clothing that started about 20 years ago, wider awareness about electric arc hazards and improvement in workplace safety standardization. However, little or no change has taken place with arc hazard assessment methods, electric-arc-rated (AR) PPE test methods, and methods of proper AR PPE selection since their original adoption in the late 1990s and early 2000s. This is reflected in the stagnant rate of electric burn trauma with thousands of cases known from available statistics outlined in Part 2 of this series of articles.
Variability of AR numerical values depending on fault current has been known since 2004, but the standardized test method for AR fabric was frozen to only one 8 kA level of test arc current. The test methods have not evolved to include a range of test currents. The fault current occurring in a workplace arc event has an extremely low likelihood of matching the fault current used in the test method. Yet, a numerical value of arc rating is directly used for PPE selection by matching the PPE arc rating to some calculated or otherwise projected value. Reliable statistical support of proper electric arc protection based on current methods of PPE selection is questionable. Nonetheless, new research on electric arc properties, material behavior and classification of arc types opens new opportunities to close existing gaps in electric arc protection.
Work, especially in construction or infrastructure renovation, often has a time value element and must continue even in adverse weather conditions. These conditions can add yet another hazard to an already potentially hazardous occupation. From 2008 to 2014, U.S. workers suffered 109 heat-related occupational fatalities (OSHA, 2015a). While occupational fatalities due to hypothermia may be less frequent, exposure to cold can result in nonfatal injuries and may lead to an increased risk of incidents. Anticipation, recognition, evaluation and control of potential heat or cold stressors can allow the job to continue safely and productively with minimal interruption.
Reasons for Concern
Heat stress includes several heat-related illnesses: heat rash, cramps and exhaustion. These are not life-threatening conditions, but can contribute to low morale, irritability and fatigue, all of which can lead to taking shortcuts or skipping procedures, which can in turn create a safety hazard.
Another serious heat-related illness is heat stroke, which is a medical emergency. A study by Gubernot (2015) indicates that the construction industry experiences the second-highest rate of occupational heat fatalities (Table 1).
NIOSH (2016b) distinguishes between classical heat stroke and exertional heat stroke. Classical heat stroke is due to exposure to a hot, humid environment especially over the course of several days. It is commonly seen in older people or those with chronic illnesses. Exertional heat stroke, more commonly seen in the workplace, is caused by intense physical activity, especially workers who are not acclimated to high temperatures. Individual characteristics (e.g., age, health status), type of activity (e.g., sedentary vs. strenuous exertion) and symptoms (e.g., sweating vs. dry skin) vary between these two classifications. This article focuses on exertional heat stress and stroke.
Improving ergonomics to prevent musculoskeletal disorders (MSDs) is a key element of OSH programs for most organizations. MSDs are a major cause of losses and a persistent source of frustration. The authors have heard from OSH managers about the challenges in proving to their top managers the effectiveness and value of their current ergonomics program. Through benchmarking studies and experience working with Fortune 1000 companies, the authors have determined that the success or failure of an organization’s ergonomics program depends on the selection of a few correct measures. Unfortunately, traditional lagging safety measures, specifically injury/illness rates, are still used by many safety managers to drive struggling ergonomics programs (Aon, 2016; Humantech, 2011). The OSH profession has identified reliance on lagging measures as a root cause for failed and ineffective ergonomic improvement programs.
This article details the few leading measures specific to MSDs that are proven to ensure leadership support and resources, and to sustain the ergonomic improvement program across multiple locations and across time. It also provides definitions and illustrations of different types of measures to enable OSH managers to better evaluate and select the optimal measures for their organizations.
Traditional Safety Measures Applied to MSD Management
To understand the best measures for managing MSDs, one must understand the foundation of the most commonly used safety measure, the injury/ illness rate. Use of this lagging measure began in 1972, with reporting injuries and illnesses to Bureau of Labor Statistics (BLS) through the Survey of Occupational Injuries and Illnesses (SOII), and it became the basis for the OSHA recordkeeping requirements in 1978 (OSHA, 2009).
Part 1 of this series of articles identifies electric arc classification, properties, behavior and methods of thermal energy dissipation among the different types of arcs, and factors for the future progress in electric-arc-rated (AR) PPE quality and reliability. Understanding the properties and behaviors of the different possible types of electric arcs is key to assessing AR PPE.
New knowledge of electric arc classification is helpful not only in current arc incident investigation but also in better understanding past arc incidents. Analysis of specific electric arc incidents is complemented with extensive research on electrical trauma trends based on government data. Part 2 of this series addresses arc hazards, protection fundamentals, and data on electrical fatalities and arc burn trauma.
Fundamentals of Electric Arc Protection
Electric Arc Hazards
Electric arc hazards are not limited to the thermal effect. Large amounts of thermal energy released in the electric arc event is also accompanied by extremely bright light flash, momentary and residual flames, heavy smoke and poisonous fumes, loud sound and molten metal droplets. Pressure waves and flying projectiles are also likely as a result of air pressure build-up with cabinet rupture due to the extreme pressure from arcing inside the enclosed cabinet.
All kinds of AR PPE are first and foremost designed and tested to protect the body, hands, face and head from thermal effects. AR PPE may provide supplementary protection against light flash, molten metal and projectiles, but it provides limited protection against smoke, sound and chronic effects from stress caused by the arc event.
According to Bureau of Labor Statistics (BLS, 2016), 4,836 fatal work injuries were recorded in the U.S. in 2015. Stated differently, 13 American workers are tragically and unnecessarily taken from their families every day. These statistics underscore the urgent need for safer workplaces.
When the author joined the safety and health department of his former employer, he knew the company was facing some tough OSH-related challenges. To say that the employer was in deep trouble was an understatement. A few weeks after the author’s arrival at the Flint, MI, manufacturing plant, the trouble signs were too many to miss.
The 700-person, round-the-clock plant was operating at an anemic 49% efficiency, while corporate management expected a minimum efficiency of 85%. The plant also had an OSHA incidence rate of 12.6 (3.5 points higher than the industry average), high turnover, high workers’ compensation costs and a strained relationship with Michigan-OSHA (MIOSHA).
Hourly workers voiced persistent criticism of virtually every aspect of the plant, and of safety and health in particular. No matter what plant management did, it could not shake the perception that it was indifferent to employees’ safety and health. In addition, several OSHA citations originating from employee complaints led MIOSHA to put the plant on its radar. The persistent OSH-related problems (e.g., ergonomics, machine guarding, housekeeping, lockout/tagout) not only were detrimental to productivity, quality and employee morale, but also had resulted in turnover of OSH professionals. The author was the plant’s third OSH professional in less than a year.
In the course of their daily lives, people selectively attend to available information and render judgments about the state of the world. These occur in various contexts including judgments concerning one’s own performance (e.g., how well am I currently doing at this task?) or the amount of risk associated with a given situation. People also carry out, sometimes immodestly, general self-appraisals, evaluating how skillful or capable they are in different contexts. People’s perceptions of the world and of their own efficacy and ability can have important implications concerning their decision making and consequent behaviors.
From a safety perspective, it is critical to understand situations where people’s perceptions or subjective appraisals deviate from objective reality. For example, a fatigued driver may elect to continue driving because he fails to adequately recognize the signs of fatigue or overestimates his ability to safely drive. Or an inexperienced driver may be overconfident in her driving skills and abilities, and travel at a high speed on a slippery surface. Gaps in subjective and objective measures have been related to calibration, a concept that has been broadly studied in many disciplines (Zell & Krizan, 2014).
This article reviews some extant literature on calibration in various domains, and describes a conceptual driver-focused framework that depicts calibration in the context of human information processing (attention) and an array of local and global contextual factors. It also describes the implications for organizational applications and the role of new automotive technology. Lastly, it discusses potential inroads for addressing the issues of calibration in the work setting.