Musculoskeletal concerns do not justify failure to use safer sequential trigger to prevent acute nail gun injuries.

BACKGROUND: Acute nail gun injuries can be controlled significantly by using tools with sequential triggers and training. Concern has been raised that sequential triggers, which require that the nose piece of the gun be depressed prior to pulling the trigger, could increase risk of musculoskeletal problems. METHODS: We conducted active injury surveillance among union carpenter apprentices to monitor acute injuries and musculoskeletal disorders between 2010 and 2013. RESULTS: Acute injury risk was 70% higher with contact trip rather than sequential triggers. Musculoskeletal risk was comparable (contact trip 0.09/10,000 hr (95% CI, 0.02-0.26); sequential 0.08/ 10,000 hr (95% CI 0.02-0.23)). CONCLUSIONS: Concern about excess risk of musculoskeletal problems from nail guns with sequential triggers is unwarranted. Both actuation systems carry comparable musculoskeletal risk which is far less than the risk of acute injury; there is clearly no justification for failure to prevent acute injuries through use of the safer sequential trigger.

Safety, incentives, and the reporting of work-related injuries among union carpenters: "you're pretty much screwed if you get hurt at work".

BACKGROUND: In the high-risk construction industry little is known about the prevalence or effects of programs offering rewards for workers and/or their supervisors for improved safety records or those that punish workers in some way for injury. METHODS: We conducted an anonymous survey of 1,020 carpenter apprentices in three union training programs to document prevalence of their exposure to such efforts. We explored associations between perceptions of the reporting of work-related injury and elements of these programs. RESULTS: Fifty-eight percent (58%; n = 592) reported some safety incentive or negative consequence of work-related injuries on their current jobsite. Reporting of work-related injuries was 50% less prevalent when workers were disciplined for injury experiences. Otherwise, we saw minimal evidence of association between injury reporting practices and safety incentive programs. However, considerable evidence of fear of reprisal for reporting injuries was revealed. Less than half (46.4%) reported that work-related injuries were reported in their current workplace all or most of the time; over 30% said they were almost never or rarely reported. CONCLUSIONS: There are multiple layers of disincentives to the reporting of work-related injuries that hamper understanding of risk and pose threats to workplace safety and productivity. These pressures do not arise in a vacuum and are likely influenced by a host of contextual factors. Efforts that help us understand variation across jobsites and time could be enlightening; such inquiries may require mixed methodologies and should be framed with consideration for the upper tiers of the public health hierarchy of hazard control.

Buyer beware: personnel selling nail guns know little about dangerous tools.

BACKGROUND: Nail gun use is ubiquitous in wood frame construction. Accessibility and decreasing costs have extended associated occupational hazards to consumers. Compelling evidence documents decreased injury risk among trained users and those with tools with sequential triggers. To prevent inadvertent discharge of nails, this safer trigger requires the nose be depressed before the trigger is pulled to fire. The sequential trigger is not required by the Consumer Product Safety Commission (CPSC) or the Occupational Safety and Health Administration (OSHA) nor are there any guidelines for training. METHODS: We collected data from personnel at 217 points of sale/rental of framing nail guns in four areas of the country. RESULTS: Sales personnel had little understanding of risks associated with use of framing nail guns. Individuals who had used the tool and those working in construction outlets were more likely to be knowledgeable; even so, less than half understood differences in trigger/actuation systems. CONCLUSIONS: Consumers, including contractors purchasing for workers, cannot count on receiving accurate information from sales personnel regarding risks associated with use of these tools. The attitudes and limited knowledge of some sales personnel regarding these potentially deadly tools likely contributes to a culture accepting of injury. The findings demonstrate how influences on the culture of construction are not limited to workers, employers, or the places construction gets done.

Fall hazard control observed on residential construction sites.

BACKGROUND: Falls are a leading cause of mortality and morbidity in the construction industry. This study measured fall hazards at residential construction sites. METHODS: Trained carpenters administered the St. Louis Audit of Fall Risks and interviewed carpenters. The prevalence of fall prevention practices meeting safety criteria was counted and correlations explored. RESULTS: We identified a high prevalence of fall hazards at the 197 residential sites audited. Roof sheathing met safety criteria most consistently (81%) and truss setting least consistently (28%). Use of personal fall arrest and monitoring of unguarded floor openings were rare. Safer performance on several scales was correlated. Construction sites of large-sized contractors were generally safer than smaller contractors. Apprentice carpenters were less familiar with their employers' fall prevention plan than experienced workers. CONCLUSIONS: Safety could be improved with consistent use of recognized fall prevention practices at residential construction sites.

How much time is safety worth? A comparison of trigger configurations on pneumatic nail guns in residential framing.

OBJECTIVE: Nail gun injuries are among the most common in wood frame construction. Despite evidence that the majority of injuries from unintentional firings could be prevented with a sequential trigger mechanism on the tools, the safer trigger has not been embraced in the fast-paced residential construction industry. An experiment was conducted in an attempt to realistically evaluate the magnitude of productivity concerns. METHODS: Ten journeymen carpenters built a yard shed on two occasions, using nail guns with two different trigger configurations, alternately, under controlled conditions. Mean differences in time required, nails used, and proper placement were evaluated considering the trigger used and whether the building was the carpenter's first or second project. RESULTS: The sequential trigger tool required a mean of 10 additional minutes of active nailing time, which represented 10% of mean nailing time (97 minutes) but only 0.77% of the total mean work time (1,298 minutes) to construct each shed. No significant differences were observed in nail count or placement. The majority of the time variability was related to who was using the tool, rather than the type of tool in the person's hand. CONCLUSIONS: Productivity concerns should focus more on improving the skill of the carpenter rather than on the trigger mechanism. Failure to place tools with the safer trigger configuration, which requires the nose piece to be depressed before the trigger is pulled, in the hands of workers does not make sense given the frequency and potential repercussions of injuries associated with the use of these tools in wood framing.

Prevention of traumatic nail gun injuries in apprentice carpenters: use of population-based measures to monitor intervention effectiveness.

INTRODUCTION: Nail guns are responsible for a significant injury burden in residential construction. Risk, based on hours of work, is particularly high among apprentice carpenters due in part to more frequent exposure to tool use. METHODS: Nail gun injuries were evaluated over 3 years among carpenters enrolled in two apprenticeship programs in the Midwest (2.3 million residential work hours observed) following initiation of training and a voluntary ANSI standard change calling for safer sequential triggers on framing nailers. Injury rates, based on hours of tool use, were calculated yearly. Rates and adjusted rate ratios were calculated with Poisson regression. Attributable risk percent (AR%) and population attributable risk (PAR%) were calculated yearly for modifiable independent risk factors for injury including lack of training in tool use and type of trigger mechanism on tools being used. RESULTS: As apprentices received training and safer trigger mechanisms became more widespread, injury rates decreased significantly (31%). While school training and hands-on mentoring were both important, injury rates were lowest among apprentices who received both. Although injury rates changed over the observation period, the relative risk comparing trigger mechanisms did not; contact trip triggers consistently carried a twofold risk. CONCLUSIONS: Although training and safer trigger use both increased, because of the relative prevalence of training and trigger exposures in this population, the engineering solution consistently had the potential to make more difference in population risk. Our findings demonstrate the utility of observational methods including measures of population-based risk in monitoring intervention effectiveness and making recommendations that lead to injury reduction.

Smiles, turnout, candidates, and the winning of district seats.

Research has shown that a candidate's appearance affects the support he or she receives in elections. We extend this research in this article in three ways. First, we examine this relationship further in a non-Western context using 2015 local elections in Japan. Next, we show that this positive relationship is more complicated depending on the characteristics of the election under consideration. Specifically, we distinguished election contests by levels of turnout and found that despite a positive relationship between turnout and the extent to which smiling increases a candidate's support levels, the marginal increase in support declined as turnout increased and, in fact, became negative when some high-turnout threshold was crossed. Finally, we show that the number of candidates competing in an election is negatively related to the impact of a candidate smiling, confirming research conducted by the Dartmouth Group.

An efficient and general approach to beta-functionalized ketones.

[structure: see text]. The oxidation of selected anions (N3-, SCN-, I-, and Br-) by ceric ammonium nitrate (CAN) in the presence of substituted cyclopropyl alcohols provides a novel approach to beta-functionalized ketones. The protocol has a number of advantages including short reaction times, ease of reagent handling, and mild, neutral reaction conditions. Overall, this method provides an alternative pathway to important starting materials and intermediates in organic synthesis.

Revisiting Pneumatic Nail Gun Trigger Recommendations.

Use of a pneumatic nail gun with a sequential actuation trigger (SAT) significantly diminishes the risk for acute traumatic injury compared to use of a contact actuation trigger (CAT) nail gun. A theoretically-based increased risk of work-related musculoskeletal disorders from use of a SAT nail gun, relative to CAT, appears unlikely and remains unproven. Based on current knowledge, the use of CAT nail guns cannot be justified as a safe alternative to SAT nail guns. This letter provides a perspective of ergonomists and occupational safety researchers recommending the use of the sequential actuation trigger for all nail gun tasks in the construction industry.

Falls in residential carpentry and drywall installation: findings from active injury surveillance with union carpenters.

Active injury surveillance was conducted with a large, unionized workforce of residential and drywall carpenters over a 3-year period. Injured carpenters were interviewed by trained carpenter investigators and sites were visited where falls occurred. Qualitative information was collected on exposures, risk perception, training, and mentoring. Falls accounted for 20% of injuries. Same-level falls were often related to weather, carrying objects-sometimes with an obstructed view-housekeeping, terrain of the lot, and speed of work. Falls from height occurred from a variety of work surfaces and involved ladders, scaffolding, roofs, work on other unsecured surfaces, unprotected openings, speed, and weather conditions. Recognized fall protection strategies, such as guardrails, toe boards, tying off to appropriate anchors, and guarding openings, would have prevented many of these falls; these practices were not the norm on many sites.

Legal dimensions of neural antecedents to voluntary action.

This article considers the arguments of Nachev and Hacker in the context of claims that Libet's experiments regarding the readiness potential pose challenges for the criminal law, specifically for the distinction between voluntary and involuntary acts.

Surveillance of nail gun injuries by journeymen carpenters provides important insight into experiences of apprentices.

Experienced journeymen conducted detailed surveillance interviews with injured apprentice carpenters (n = 413). Nail gun injuries commonly occurred due to inadvertent discharge, ricocheting or projectile nails, and penetration of the wood surface. Framing nailers with contact trip triggers were most often involved; these triggers allow nail discharge anytime the trigger and nose piece are both depressed including following recoil of the tool after firing. Injured workers made concrete and practical suggestions for prevention. Scenarios were identified where changes in work practice, safer triggers, and thoughtful training could prevent injuries. Most injuries were not reported through workers' compensation; this was often due to perceived lack of injury severity, but also involved subtle as well as overt pressures on apprentices not to report. These case-based analyses are consistent with reports that many injuries from nail guns could be prevented with existing safer trigger mechanisms and training. Efforts should also focus on improved injury reporting.

Continued progress in the prevention of nail gun injuries among apprentice carpenters: what will it take to see wider spread injury reductions?

PROBLEM: Nail guns are a common source of acute, and potentially serious, injury in residential construction. METHOD: Data on nail gun injuries, hours worked and hours of tool use were collected in 2008 from union apprentice carpenters (n=464) through classroom surveys; this completed four years of serial cross-sectional data collection from apprentices. A predictive model of injury risk was constructed using Poisson regression. RESULTS: Injury rates declined 55% from baseline measures in 2005 with early training and increased use of tools with sequential actuation. Injury rates declined among users of tools with both actuation systems, but the rates of injury were consistently twice as high among those using tools with contact trip triggers. DISCUSSION AND IMPACT: Nail gun injuries can be reduced markedly through early training and use of tools with sequential actuation. These successful efforts need to be diffused broadly, including to the non-union sector.

Nail gun injuries in apprentice carpenters: risk factors and control measures.

BACKGROUND: Nail guns increase residential construction productivity but their use is associated with risk of injury. METHODS: Active surveillance data from 772 apprentice carpenters were used to document the injury risk associated with the use of nail guns and the potential impact of modifiable risk factors. Using reported work hours and nail gun injuries injury rates per 200,000 hr worked in the past year were calculated. Using estimates of hours of tool use, Poisson regression was used to calculate adjusted rate ratios for injury associated with time in the trade, trigger mechanism on the tools and training prior to injury. RESULTS: Forty-five percent of these apprentices had sustained a nail gun injury; injury rates in the past year based on hours of work were considerably higher than previously recognized. Those with less than 1 year in the trade compared to those with more than 5 years experience (RR = 2.7; 95% CI 1.2, 5.9) and those with no training in tool use (RR = 2.9; 95% CI 1.9, 4.4) were at greatest risk. After adjusting for experience and training, the rate of injury was twice as high with tools with a contact trip trigger compared to those with a sequential trigger (RR = 2.0; 95% CI 1.2, 3.3). CONCLUSIONS: Preventive measures should include change to the safer sequential trigger that prevents unintentional firing and early training in safe tool use. Because of the high prevalence of use of tools with contact trip triggers the greatest number of injuries among these apprentices could be prevented with an engineering solution.

Work-related injuries in residential and drywall carpentry.

Findings are reported on the first two years of an active injury surveillance project designed to test the utility of active injury investigations in identifying causes of injury among a large cohort of carpenters who did residential building and drywall installation. Occupational Safety and Health Administration recordable injuries were reported by participating contractors. Injured union carpenters were interviewed by experienced journeymen trained in a standard questionnaire protocol. Enumeration of workers and hours worked were provided by the union. These data allowed the definition of a dynamic cohort of 4429 carpenters, their hours worked, detailed information on the circumstances surrounding recordable injuries, and possible preventive measures from the perspectives of the injured worker and an experienced journeyman investigator. The overall estimated injury rate (16.9 per 200,000 hours worked) was considerably higher than recent Bureau of Labor Statistics rates despite less than complete ascertainment of injuries. Injuries most commonly involved being struck by or against something, manual materials handling injuries, and falls. Manual materials handling injuries often involved very heavy objects or tasks and were injuries carpenters most often reported needs for adequate help and coordinated team work to prevent. Falls from heights occurred from a variety of surfaces and were not just injuries of inexperience. Carpenters reported the need for more attention to common fall protection practices, such as the use of more toe boards and guardrails. Poor housekeeping was involved in the majority of same level falls, as well as some manual materials handling injuries.