Evaluation of guardrail systems for preventing falls through roof and floor holes

Introduction

Fall-related occupational injuries and fatalities are serious problems in the U.S. construction industry, especially incidents related to unguarded holes. The National Institute for Occupational Safety and Health, Division of Safety Research, Morgantown, WV conducted a project to evaluate the effectiveness of guardrail systems to prevent falls through roof and floor holes.

Methods

Two commercial edge-protection products were evaluated when used as perimeter guarding around a roof hole. Installations of the commercial products were compared to job-built guardrails constructed of 2^″ × 4^″ construction-grade lumber. Occupational Safety and Health Administration (OSHA) regulations require that “a force of at least 200 pounds” must be supported by the top rail of a guardrail system “in any outward or downward direction at any point along the top edge.” A laboratory testing system was developed to evaluate this requirement. A dynamic 200-lb force was generated against the top rail using a weighted manikin mounted on a hinged steel frame. Nine construction workers, who served as test subjects, each built five different guardrail configurations.

Results

All 45 configurations met the 200-lb OSHA requirement. Installation time for one commercial product was 32% quicker than the job-built configuration (25.6 min vs. 37.9 min).

Impact on Industry

This study: (a) indicates that the two edge-protection products can be used as perimeter guarding; (b) highlights the importance of using proper materials and fasteners to construct guardrails to protect workers from falling into unguarded roof and floor holes; and (c) discusses an overall-strength-testing methodology that can be used by fall-protection researchers.     

The NIOSH Construction Program: Research to practice, impact, and developing a National Construction Agenda

The U.S. National Institute for Occupational Safety and Health (NIOSH) conducts research to improve and protect the health and safety of workers. This paper describes the experience of the NIOSH Construction Program with two recent program planning initiatives intended to improve the program: (a) an independent external review of work over the past decade and (b) the development of strategic goals organized into a “National Construction Agenda” to guide a decade of future work. These goals, developed with input from construction industry stakeholders and researchers, are a part of the NIOSH National Occupational Research Agenda (NORA) initiative. The NORA goals are intended to provide an ambitious set of goals for all construction stakeholders to work together on. Both efforts relate to insuring the relevance and impact of research, reflecting an emerging policy perspective that research programs should be judged not just by the quality and quantity of science produced, but by the industry impact and tangible benefit resulting from the research. This paper describes how views on research planning have evolved to incorporate lessons learned about how research leads to improved safety and health for workers. It also describes the process used to develop the goals and the resulting strategic and intermediate goals that comprise the National Construction Agenda.     

Preparedness for anthrax attack: the effect of knowledge on the willingness to treat patients

Little is known about the factors that may impact on the willingness of physicians and nurses to treat patients during a bioterrorism attack. This survey was conducted among 76 randomly selected nurses and physicians in the emergency rooms of three public hospitals in order to analyse the relationship between knowledge, profession and the willingness to treat anthrax. The study finds that the willingness of physicians and nurses to come to work is 50% greater among the group with the highest knowledge about anthrax (P < 0.0001). Within that group, the willingness to treat patients suspected of being infected with anthrax was 37% greater (P < 0.0001) and the willingness to treat patients diagnosed with anthrax was 28% greater (P = 0.004) than in the other groups. These results imply that enhancement of knowledge among health care workers may improve their willingness to come to work and treat patients infected with anthrax during a bioterrorism attack.     

洪涝灾害经济易损性模糊评价——以安徽沿长江地区为例

洪水灾害是洪水危险性对承灾体易损性综合作用的结果,由于降水量、人口密度、产值等因子在洪水易损性中的作用具有模糊性,因此运用模糊模型进行评价有一定意义。以安徽沿长江地区为例,在GIS和模糊数学法的支持下,建立了基于GIS的模糊综合评价模型,对洪水灾害经济易损性风险进行了评价与分析,将安徽沿长江地区洪涝的易损性程度划分为5个等级:高度易损性、较高度易损性、中度易损性、较低度易损性、低度易损性。研究结果表明:沿江洪水灾害易损性总体水平较高,特别是在马鞍山、芜湖市、铜陵市等经济发达、人口密集、耕地面积广阔的滨江下游平原区。这些地区应积极兴修水利,大力发展避洪产业。     

京津唐地区地震灾害区域宏观脆弱性变化研究

研究灾害脆弱性的变化有助于深入理解灾害及灾害风险的形成机制。在重新审视承灾体系统灾害脆弱性的分析层次和描述角度之后,深化了对地震灾害区域宏观脆弱性的影响因素和描述指标的再认识,完善了以主成分分析为核心技术的分析该类脆弱性时空变化的数理方法。以此为基础,以1985、1995、2000和2004年为代表时期,对京津唐地区20多年来的地震灾害区域宏观脆弱性的变化做了进一步的分析和总结。主要结论是:研究区地震灾害区域宏观脆弱性20多年来的时空变化可分解为少数几种脆弱性模式的变化;1985年以来,该类脆弱性的空间分异格局整体稳定;但是,各地自身脆弱与否的程度20多年来的变化却很显著——各大中城市市区的脆弱程度显著增强,其他地区整体减弱,且变化幅度前者显著大于后者;研究区地震灾害区域宏观脆弱性的时空变化主要受该地区的人口和经济特别是工商业经济的增长、城市化发展和产业结构的调整等3方面因素所驱动。     

西苕溪中上游流域水生甲虫分布与环境的关系

水生甲虫(昆虫纲,鞘翅目)群落结构受多种环境因素的制约.西苕溪中上游流域38个样点共发现水生甲虫12科36个分类单元.优势属是长角泥甲科的Stenelmis属和扁泥甲科的Psephenoides属,出现频度分别为30和22,但有29属的出现频率不大于5.典范对应分析(CCA)表明,鞘翅目群落组成受荫蔽度、总氮、电导率和栖境质量影响最大.样点环境指标聚类结果与CCA结果一致,样点被分为3组.从第1组至第3组,水体中的总氮(2.80→3.52 mg/L)和化学需氧量(14.5→20.29 mg/L)明显上升,荫蔽度(18→6)明显降低.第1组(18个分类单元)和第3组(16个分类单元)的水生甲虫种类组成差异极显著(P＜0.01),第2组水生甲虫多样性最高(26个分类单元).Macronychus,Zaitzevia,Scirtes,Stenocolus,Berosus,Laccobius和Ectopria属可作为清洁水体指示生物,Hydrocassis和Ancyronyx属是重污染水体指示生物.图3表4参16     

基于试验观测的光合有效辐射特征分析

光合有效辐射是生物、生态和农业常用的重要参数,常规气象资料中没有该资料,实测结果也比较少,以往多采用经验气候学计算获得。论文基于固城站观测辐射资料,对光合有效辐射特征分析的结果表明:光合有效辐射（PAR）占总辐射（Q）的比值(η_PAR)分布呈近似钟型,有60%的比值分布在0.35～0.45之间。η_{PARPARPARPARPAR})与Q的关系为:全年Q_PAR=0.40Q,生长季Q_PAR=0.41Q,这一结果与以往国内一些实测结果相近。论文用此值重新评估华北平原光合生产潜力的结果表明,以往估算光合生产潜力常采用η_PAR     

上海城市内河生态系统服务的条件价值评估

条件价值评估法(CVM)是估算生态系统服务最主要的技术方法之一。浦东张家浜的综合整治为全国河道整治的样板工程,笔者采用CVM引出张家浜沿线居民对改善张家浜生态系统的平均支付意愿(528 8元 a),初步估算出张家浜综合整治后的生态系统服务价值约为3 014～5 262亿元 a。讨论了导致支付意愿产生偏差的各方面原因,研究了张家浜沿线居民对张家浜整治项目的支付意愿和被调查者收入、年龄、受教育程度等因素的关系。最后提出了CVM研究结果的可靠性和国内在CVM研究中亟待解决的问题。      

甘肃省迭部县居民森林生态环境支付意愿影响因素分析

公众的生态环境认知水平及支付意愿对森林生态环境保护具有重要的影响和作用.根据甘肃省迭部县居民的291份有效调查问卷,采用描述性统计方法和结构方程模型对森林生态环境支付意愿的影响因素进行了分析.结果表明:①居民对生态环境服务价值的认知、对生态环境补偿的认知、对生态环境保护的预期收益、居民个人资金技术因素、外部环境因素与居民森林生态环境支付意愿之间存在正相关关系,且影响显著,其中影响程度最大的是外部环境因素,标准相关系数为0.830,解释效果良好,影响程度最小的是资金技术因素,相关系数仅为0.283.②多群组结构方程模型研究结果显示,男性居民的森林生态环境支付意愿主要受对森林生态环境认知程度的影响,女性更容易受外部环境因素的影响.不同年龄段的居民在森林生态环境服务价值认知、资金技术因素和外部环境因素方面存在差异性.不同教育程度居民之间的差异主要体现在对森林生态环境服务价值的认知和对森林生态环境补偿的认知上.③性别、年龄、教育程度等因素对生态环境服务价值认知、预期收益等有显著影响,且不同因素的影响程度存在差异.研究显示,对森林生态环境支付意愿影响因素分析反映了环境支付意愿的普适性问题,研究结果可为生态资源和环境管理等提供参考.