A Contribution to the Study of the Antidust Respirators’ Real Performance

In most industrial enterprises, hazardous factors are present in quantities exceeding permissible levels. Such a situation requires using antidust respiratory protection. It has been suggested, however, that filters for respirators are not assessed properly and that lab results might not be related to real filtering efficiency in industry. This article contains test results of some commercially available filtering half-masks, including the effect of loading with real dust, high humidity, high temperature, and a combination of loading with dust and high humidity on the half-masks’ performance. The results show that the effect of these factors is considerable and that a combination of loading with silica dust and exposing to high humidity can cause a complete loss of performance.     

Thermal Strain in Fire Fighters While Wearing Task-Fitted Versus EN 469:2005 Protective Clothing During a Prolonged Rescue Drill

Fire fighters are normally overprotected during their working hours because of the tendency to keep the personal protection level sufficiently high in case of the worst possible scenarios. This study investigated the effects of task-fitted protective clothing on thermal strain in fire fighters as compared to EN 469:2005 protective clothing during a prolonged (2 1/2 hrs) job-related rescue drill under neutral and hot climates. The subjects were 23 healthy, physically fit professional male fire fighters aged 26–44 years. Measurements included cardiovascular and thermal responses and subjective assessments. Wearing task-fitted clothing during rescue tasks in a neutral climate considerably reduced total thermal and cardiovascular strain in prolonged rescue work. The fire fighters also perceived physical work as significantly harder on average, and reported more intense subjective discomfort while wearing EN 469:2005 as compared to task-fitted clothing.     

Deposition and Resuspension of Selected Aerosols Particles on Electrically Charged Filter Materials for Respiratory Protective Devices

The primary aim of the study was to analyse the non-steady state of filtration for selected electrostatic filter materials designed for use in respiratory protective devices. The obtained results showed that the filtration process in electrostatic filters was dependent in the main on the following factors: type of the filter material, electrostatic field strength of the material, and the charge of the aerosol.

To a lesser degree the filtration process depended on the sign of the charge and the relative humidity of the air. A significant correlation was found between the increase in the penetration and the decrease in breathing resistance while the filter was being loaded.

The effect of resuspension (tearing off and re-deposition of dust agglomerates inside the filter) on the filtration process very significant. It was also observed that under certain conditions electrostatic filter materials lost their protection properties.     

活性炭复合床层对动活性的影响试验

本文通过对KZ1床层、KZ2床层、KZ1和KZ2复合床层在不同床层厚度条件下,对氯化氰蒸气的动活性进行对比试验,并对试验结果进行分析,得出了后者并非前两者之和,而有了大幅提高的结论。     

下保护层开采卸压瓦斯治理技术研究

以潘一东矿1252（1）下保护层首采工作面为研究对象,采用分源预测法对下保护层工作面瓦斯涌出情况进行预测。计算结果表明,1252（1）工作面的瓦斯有六成左右来自上邻近13—1煤层,在本煤层回采期间提出了地面钻井、底抽巷穿层钻孔、高位钻场顶板走向钻孔、沿空留巷充填墙埋管等瓦斯治理方案,抽采率达到90％左右,工作面上隅角完全杜绝瓦斯浓度超限现象,保护范围内的13—1煤层的突出危险性也显著降低。     

浪涌防护设计思路与常见防护电路

浪涌冲击是电子产品的常见问题之一,它经常造成产品损坏。浪涌防护一直以来是令电子产品设计者头痛的问题。本文从原理上,介绍几种浪涌防护设计的思路与方法,并结合具体案例与电路原理图,进行深层剖析,以期能提供借鉴作用。     

调节风窗对瓦斯爆炸影响的数值分析*

为研究调节风窗的面积、位置对瓦斯爆炸传播特性的影响,通过FLACS软件构建不同面积和不同位置调节风窗的风门-巷道模型,对瓦斯在该模型中的爆炸及其传播进行数值模拟,并分析瓦斯爆炸压力、火焰传播速度。研究结果表明:风门前最大瓦斯爆炸压力值与调节风窗边长呈现指数减小关系,而风门后最大瓦斯爆炸压力值与调节风窗边长呈现指数增加关系;火焰传播速度与调节风窗边长呈现指数增加关系;相同面积情况下,调节风窗中心位置对瓦斯爆炸影响较小。     

冷循环便携式半导体降温服设计及制冷性能分析

为缓解高温环境下劳动人员面临的热害问题,设计1种利用半导体制冷片作为制冷源的便携式冷循环降温服,并在高温环境下测试其降温性能.结果表明:在总电源功率100 W、环境温度30℃的情况下,运行12 min后,制冷水温度降低至15.7℃.降温服稳定运行状态下制冷功率为340.4 W.系统运行环境温度对制冷系统的制冷性能有显著...     

海五联区域阴极安全保护智能监测系统

阐述了ACPS-Ⅱ阴极安全保护智能监测系统的组成、特点以及在海五联合站的应用,指出阴极安全保护监测技术是阴极安全保护技术的发展方向,有着广泛的推广应用前景.     

杂物梯门电联锁的设计与改进

提出了杂物梯门电联设计装配不合理等问题,并对其进行了设计与改进。