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991.

Background

This study compared driving exposure between two high-crash-risk groups (16–17 and 18-24-year-olds), with a low-crash-risk group (35-64-year-olds). In addition, patterns of association between driving exposure measures and demographic and driving behavior variables were examined.

Methods

Respondent's total miles, minutes, and trips driven were calculated within a 48-hour period, using state-wide survey data collected in 2004 and 2005.

Results

The youngest drivers drove fewer miles and minutes, but a comparable number of trips as the two older groups. Employment and high vehicle access were associated with greater driving exposure for 16-17-year-olds and 18-24-year-olds. Employment, high household income, large household size, and low vehicle access were associated with greater driving exposure for 35-64-year-olds. More driving was done alone than with passengers present and during the day than at night across all ages. There was a positive association between two driving exposure measures (miles and minutes driven) and demographic and driving behavior variables, which did not extend to trips driven.

Discussion

Driving exposure is directly related to stage of life. The entire sample of 16-17-year-old respondents were in high school, which directly influenced their driving times, destinations, and purpose. Those aged 18–24 years displayed driving behavior patterns that were closer to the older drivers, while retaining some differences. The oldest drivers were likely to be shouldering the greatest household responsibilities, and their greater driving exposure may reflect this reality.

Impact on industry

These findings provide new information about driving exposure for two high-risk and one low-risk group of drivers. They also raise concern over potential workplace safety issues related to teens’ higher driving exposure, and concomitant crash risk, related to being employed. Future research should examine this issue more carefully so that evidence based recommendations can be made to enhance the safety of teens who are employed, especially those who are employed as drivers.  相似文献   
992.
Learning from incidents is considered a very important source for learning and improving safety in the process industries. However, the effectiveness of learning from reported incidents can often be questioned. Therefore, there is a need to be able to evaluate the effectiveness of learning from incidents, and for that purpose we need methods and tools. In this paper, a method is described for evaluating the effectiveness of learning, based on the idea of “level of learning” of the lessons learned. The level of learning is expressed in terms of how broadly the lesson learned is applied geographically, how much organizational learning is involved and how long-lasting the effect of learning is. In the 6-step method, the incidents reported in a typical incident learning system are evaluated both for the actual and the potential level of learning in a semi-quantitative way with different tools. The method was applied in six process industries on a large number of incidents. The method was found to be very useful and to give insights of aspects that influence the learning from incidents.  相似文献   
993.
Usage of anticoagulant rodenticides (ARs) is an integral component of modern agriculture and is essential for the control of commensal rodent populations. However, the extensive deployment of ARs has led to widespread exposure of a range of non-target predatory birds and mammals to some compounds, in particular the second-generation anticoagulant rodenticides (SGARs). As a result, there has been considerable effort placed into devising voluntary best practice guidelines that increase the efficacy of rodent control and reduce the risk of non-target exposure. Currently, there is limited published information on actual practice amongst users or implementation of best practice. We assessed the behaviour of a typical group of users using an on-farm questionnaire survey. Most baited for rodents every year using SGARs. Most respondents were apparently aware of the risks of non-target exposure and adhered to some of the best practice recommendations but total compliance was rare. Our questionnaire revealed that users of first generation anticoagulant rodenticides rarely protected or checked bait stations, and so took little effort to prevent primary exposure of non-targets. Users almost never searched for and removed poisoned carcasses and many baited for prolonged periods or permanently. These factors are all likely to enhance the likelihood of primary and secondary exposure of non-target species.  相似文献   
994.
汽车气候老化主要环境影响因素分析   总被引:3,自引:0,他引:3  
随着我国汽车产业的快速发展,人们对汽车品质的要求越来越高,汽车的气候老化问题也越来越受到关注,本文从汽车整车自然暴露试验展开研究,针对汽车气候老化主要环境影响因素——太阳光辐射、温度和湿度进行分析,为真实模拟人工老化试验技术提供基础依据,为选择合适的汽车气候老化试验方法提供技术参考.  相似文献   
995.
对国外最新的人造纳米颗粒的暴露评价方法和研究结果进行综述,旨在为我国今后工作现场的职业卫生暴露评价提供指导。检索和查阅2000—2010年发表的涉及纳米颗粒暴露评价的同行评审期刊的英文文献和报告,并对暴露评价设备和方法进行比较和分析,归纳描述部分研究结果,总结纳米颗粒暴露评价的特殊性和挑战,探讨解决这些问题的关键步骤。最后,提出今后在职业现场开展纳米暴露评价的2个可行的方法。  相似文献   
996.
为了解我国农民工参加工伤保险的影响因素,提高农民工工伤保险的参保率,通过对全国9个省市共3 848名农民工的问卷调查,应用Logistic回归模型分析政策的因素和企业的因素对农民工参加工伤保险的影响。结果表明,农民工是否参加工伤保险受到各地工伤保险政策以及农民工所在企业两方面的影响。从政策的角度看,个体工商户参加工伤保险的规定、工伤保险基金的统筹水平以及工伤保险的偿付方式对农民工参加工伤保险有显著影响;从企业的角度看,农民工所在企业是否建有工会、企业所有制对农民工参加工伤保险有显著影响。建议各地进一步明确工伤保险政策中对个体工商户的参保要求,继续提高工伤保险基金的统筹水平,增加农民工领取工伤保险偿付的方式。建议劳动保障部门加强对未建有工会的企业,加强对私企,特别是个体工商户的监察力度。  相似文献   
997.
基层应急体系现状调查分析   总被引:1,自引:0,他引:1  
通过发放调查问卷和实地走访的形式,对基层应急体系存在的问题做出详细的分析,发现其应急预案体系、人员队伍及公众的培训教育、应急物资储备及应急管理社会参与程度都存在很多的不足,并提出完善预案体系、组织管理体系和推进应急队伍建设、应急物资建设、公众的教育培训和强化防灾应急演练及防灾减灾活动等相应的具体措施,从而全方位稳步推进基层应急体系的建设。  相似文献   
998.
Water use efficiency (WUE) is an important variable used in climate change and hydrological studies in relation to how it links ecosystem carbon cycles and hydrological cycles together. However, obtaining reliable WUE results based on site-level flux data remains a great challenge when scaling up to larger regional zones. Biophysical, process-based ecosystem models are powerful tools to study WUE at large spatial and temporal scales. The Integrated BIosphere Simulator (IBIS) was used to evaluate the effects of climate change and elevated CO2 concentrations on ecosystem-level WUE (defined as the ratio of gross primary production (GPP) to evapotranspiration (ET)) in relation to terrestrial ecosystems in China for 2009-2099. Climate scenario data (IPCC SRES A2 and SRES B1) generated from the Third Generation Coupled Global Climate Model (CGCM3) was used in the simulations. Seven simulations were implemented according to the assemblage of different elevated CO2 concentrations scenarios and different climate change scenarios. Analysis suggests that (1) further elevated CO2 concentrations will significantly enhance the WUE over China by the end of the twenty-first century, especially in forest areas; (2) effects of climate change on WUE will vary for different geographical regions in China with negative effects occurring primarily in southern regions and positive effects occurring primarily in high latitude and altitude regions (Tibetan Plateau); (3) WUE will maintain the current levels for 2009-2099 under the constant climate scenario (i.e. using mean climate condition of 1951-2006 and CO2 concentrations of the 2008 level); and (4) WUE will decrease with the increase of water resource restriction (expressed as evaporation ratio) among different ecosystems.  相似文献   
999.
The residual levels of polycyclic aromatic hydrocarbons (PAHs) in the liver, brain, gill and muscle tissues of four common edible freshwater fish species including crucian carp, snakehead fish, grass carp and silver carp collected from Lake Small Bai-Yang-Dian in northern China were measured by GC-MS. The distribution and composition pattern of PAHs in the fish tissues, and the effects of lipid contents in fish tissues and the octanol-water partition coefficient (Kow) of PAHs congeners on them were analyzed. The human health risk of PAHs though fish consumptions was estimated. The following results were obtained: (1) The average residual levels of total PAHs (PAH16) on wet weight base in the different tissues of each fish species ranged from 4.764 to 144.254 ng/g ww. The differences in the average residual levels on wet weight base for PAH16 within four fish species were not statistically significant (P > 0.05); however, these within four fish tissues were statistically significant (P < 0.01). (2) There were very similar distribution patterns of PAH congeners among both the fish tissues and the fish species, as indicated by statistically significant positive interrelationships (R = 0.58-0.97, P < 0.01 or P < 0.05). Low molecular weight (LMW) PAHs predominated the distribution in the fish tissues, accounting for 89.97% of total PAHs. Phe was the most dominant component, according for 37.79% of total PAHs, followed by Ant (18.59%), Flo (12.59%), Nap (10.79%), Fla (9.82%) and Pyr (6.43%). (3) The PAHs residues and distribution in the fish tissues are dependent on both the Kow of PAH congeners and the lipid contents in the fish tissues. There was a significant positive relationship (R = 0.7116, P < 0.0001) between lipid contents and PAHs residual levels. The statistically significant negative relationships (P < 0.05) were found between LogKow and log-transformed PAHs contents on wet weight base for all fish tissues except for the muscle tissue of snakehead fish, the brain and liver tissues of crucian carp. (4) The risk levels of total PAHs were lower than 10−5 for the muscle tissues of four studied fish species and for the brain tissues of grass carp and snakehead fish; while these were higher than 10−5 for the brain tissues of crucian carp and silver carp. The risk levels of total PAHs in the liver tissues of four studied fish species except for snakehead fish exceeded 10−5 for 2-4.5 times. However, the potency equivalent concentration (PEC) of total PAHs in four studied fish tissues were still lower than the maximum permissible BaP limits for crops and baked meat and for plants in the national criterions. The distributions of PAH congeners in fish were well simulated by a level III fugacity model, especially for low molecule weight PAHs.  相似文献   
1000.
我国油站量油技术与油气排放浅析   总被引:1,自引:0,他引:1  
论述工加油站油气排放控制与运油罐车、地下储罐量油方式的关系,概述了我国加油站量油方式的现状,以及人工测量和液位仪密闭自动测量两种量油方式。综述了电容式液位仪、超声波液位仪和磁致伸缩式液位仪的量油原理、特点及发展趋势,重点介绍了磁致伸缩技术,并结合汽油流转过程中油气密闭性控制的重要性及储油罐的管理要求,展望了未来加油站量油方式的技术发展趋势。  相似文献   
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