坦克射击训练时舱内气体污染的测定

本研究测定了坦克射击训练时舱内气体污染的程度，及其对人体呼吸道和心血管系统的影响。结果表明：坦克实弹射击４发榴弹后，舱内总烃．ＳＯ２．ＣＯ和ＮＯｘ明显升高，虽随时间的延长而逐渐降低，但仍高于射击前，即使在通风情况下，也是如此。在此条件下，乘员的肺功能和心电图均出现一定程度的改变。提示：应采取有效的措施，以减轻有害气体对坦克乘员的影响。     

坦克作业噪声的测试与评价

目的：噪声是坦克作业时危害人体健康和工效的主要因素之一，了解坦克运行时和炮击时车内噪声的分布情况，以及对人体听觉的影响，为进一步研究卫生防护措施提供基础性资料。方法：在现场用某型坦克进行试验，测定连续运行和实弹射击时的噪声，分析其频谱，并测定乘员的听力变化。结果：行驶时连续噪声为107－112dB(A),能量主要集中在300Hz左右，炮击时车内脉冲噪声为167－172dB(P),B-持续时间多为300－400ms，3h作业后乘员有轻度听力阈移。结论：根据有关卫生标准对结果进行的评价显示，坦克乘员的听力保护应加强。     

噪声与其他有害因素的联合作用研究进展

噪声单独作用或与其它有害因素联合作用对听觉系统、心血管系统、骨骼系统、生殖发育系统、免疫系统等产生一些不良影响,长期处在强噪声环境中还可能产生一些精神心理症状。持续暴露在较高水平的噪声中（主频率在８００ＨＺ以上）会损伤内耳的听觉细胞,诱导不可逆的听力丧失［１］。低频噪声（主频率在３００ＨＺ以下）是城市环境中普遍的背景噪声［２］,来自许多人工声源,产生的影响也较大,长期处在低频噪声中比处在相同声压水平下的较高频率的噪声中产生的不良影响更大,在低频噪声环境中某些症状会加剧,但低频噪声有时也会拮抗同时…     

5种采样袋对常见有害气体的贮存效果

在环境监测中,经常要到现场采样,而后运回分析测试。要正确反应现场的污染真实情况,除了先进、灵敏的仪器设备处,贮存样品的器具也不可忽视,它必须具有对样品不吸附、不吸收、不污染、不氧化和不还原的性能,而且还应有一定的韧性。     

常见有害气体的理化特性与中毒预防

<正>1 接触机会与物理特性1.1 有害气体与接触机会 铅、苯、汞、汽油一般引起慢性中毒,下面主要讨论常见引起急性中毒的有害气体。接触机会见表1。     

空气净化输液器对空气中有害气体吸收功效的探讨

对空气净化输液器吸收有害气体的功效进行了探索试验。从而得知，空气净化输液器对空气中有害气体SO2的吸收能力是普通输液器的100倍以上，能使三级空气达到一级水平。即使是在空气污染十分严重的地区，空气净化输液器对有害气体的净化能力也完全能够满足临床要求。     

装甲车辆噪声对乘员听力的影响

目的 探讨装甲车辆噪声对乘员听力的影响,为装甲车辆降噪技术和乘员的听力防护措施研究提供基础数据.方法 选择3种车型,每车测试2点,噪声测试仪器于试验前0.5h安装于装甲车内驾驶舱和战斗舱相应位置,在车辆行驶过程中连续测量噪声,听力在跑车前测量1次,并开展问卷调查.结果 Ⅰ、Ⅱ型车驾驶舱的等效声级分别为(90.2±1.89)、(90.1±2.53)dB(A),战斗舱的等效声级分别为(108.0±2.62)、(104.9±3.28) dB(A),Ⅲ型车驾驶舱等效声级为(99.7±3.05) dB(A);Ⅰ、Ⅱ、Ⅲ型车操作乘员左右耳的语频平均听阈均高于对照;Ⅱ型车操作乘员左耳听力异常率(48.1％)和Ⅱ、Ⅲ型车操作乘员右耳听力异常率(40.7％、27.7％)明显高于对照组,差异有显著性(P＜0.05,P＜0.01);问卷调查结果显示舱室内噪声舒适性差,影响车内、车间乘员间的有效沟通.结论 装甲车内噪声对乘员的听力有较强影响,应当加强乘员听力防护和车辆降噪技术研究.     

70砂模浇钢时产生的有害气体及其浓度分布的研究

本文对某钢厂使用７０砂模铸钢时，所产生有害气体及其于车间空气中的浓度在不同时间、不同空间上进行动态的现场实验研究。其结果表明：氯气浓度均在０．２ｍｇ／ｍ３以下；氧气个别地点及个别时段略有下降；一氧化碳和二氧化碳浓度在不同时间和空间上变化呈现相似的规律性。均在浇注结束后０～３０分钟内大量产生且出现最高值，以１５分钟时段为最多，纵向浓度变化明显高于横向，均随着高度的下降而浓度上升，二氧化碳和一氧化碳两者浓度间呈正相关。提示防治危害的重点是一氧化碳和二氧化碳，地点在地坑，时间是０～３０分钟内。     

白噪声对耳蜗损伤的生理和形态学

报道125dBLp和131dBLp白噪声对耳蜗电生理(耳蜗电图和脑干诱发电位)和耳蜗形态学(扫描电镜)的影响。发现131dBLp白噪声作用下,阈移和损伤范围明显,螺旋器外毛细胞损伤范围和细胞数严重,可见30%内毛细胞Ⅰ病变。125dBLp白噪声,阈移轻,仅高频区损伤,螺旋器外毛细胞损伤范围和细胞数少,未见内毛细胞损伤。讨论了对噪声性聋的预防和治疗的重要意义。     

装配式钢工事内机枪射击噪声和有害气体对射手的影响

我们观察了轻、重机枪在装配式园堡形单孔机枪钢工事内射击时产生的噪声和有害气体对射手健康的影响。报告如下: 方法园堡形钢构件工事体积为5m~3,开有30×40cm的射击孔1个,由两名射手在内发射轻机枪弹1850发,重机枪弹200发,射击前后测量射手的体温、脉搏、血压及听力,并询问主观感觉。射击时测定工事内噪声强度,并采样分析有害气体浓度。     

An assessment of the mental status of miners exposed to the noise load

The use of psychological-and-diagnostic techniques ant tests designed to study the mental condition and to evaluate the efficiency of psychological adaptation will ensure an early detection of different disorders in the mental status of miners and a differentiation of the population according to their prevalence, which is of a great prognostication importance. The choice of the most informative indices of the miners' psychological status will make it possible to use them in evaluating the professional adaptability of young experts mastering the mining skills, which would maintain a high standard of health and labor longevity.     

噪声作业工人心电图分析

对222名噪声作业工人和700名非噪声作业工人进行常规心电图检查,并进行剂量分级和年龄分层分析。结果提示噪声导致心电图异常存在剂量—效应关系,年龄加大了噪声致工人心电图异常的危险度。     

Hearing loss in workers exposed to toluene and noise

In this study we investigated the risk of hearing loss among workers exposed to both toluene and noise. We recruited 58 workers at an adhesive materials manufacturing plant who were exposured to both toluene and noise [78.6-87.1 A-weighted decibels; dB(A)], 58 workers exposed to noise only [83.5-90.1 dB(A)], and 58 administrative clerks [67.9-72.6 dB(A)] at the same company. We interviewed participants to obtain sociodemographic and employment information and performed physical examinations, including pure-tone audiometry tests between 0.5 and 6 kHz. A contracted laboratory certified by the Council of Labor in Taiwan conducted on-site toluene and noise exposure measurements. The prevalence of hearing loss of >or=25 dB in the toluene plus noise group (86.2%) was much greater than that in the noise-only group (44.8%) and the administrative clerks (5.0%) (p<0.001). The prevalence rates were 67.2, 32.8, and 8.3% (p<0.001), respectively, when 0.5 kHz was excluded from the estimation. Multivariate logistic regression analysis showed that the toluene plus noise group had an estimated risk for hearing loss>or=25 dB, 10.9 times higher than that of the noise-only group. The risk ratio dropped to 5.8 when 0.5 kHz was excluded from the risk estimation. Hearing impairment was greater for the pure-tone frequency of 1 kHz than for that of 2 kHz. However, the mean hearing threshold was the poorest for 6 kHz, and the least effect was observed for 2 kHz. Our results suggest that toluene exacerbates hearing loss in a noisy environment, with the main impact on the lower frequencies.     

船舶噪声对船员听力影响的调查

目的 探讨船员噪声性听力损失的状况及其剂量-效应关系.方法 观察组、对照组各1 000名,分别给予纯音听力测定.检测20艘船舶不同工作场所的声级.结果 观察组听力损失较对照组明显(x2=191.66,P<0.01).机舱组听力损失较甲板组严重(x2=15.99,P<0.01).机舱与甲板噪声暴露水平均超过国家规定标准[85 dB(A)].结论 从船员噪声性耳聋的形成特点来看,它与船员工种、接触噪声时间有密切的关系.     

Hearing health of workers exposed to noise and insecticides

OBJECTIVE: To examine the peripheral auditory disorders in a group of workers exposed to organophosphate and pyrethroid insecticides, used in vector control campaigns. METHODS: The prevalence study examined a population of 98 individuals who sprayed insecticides in campaigns for the prevention of Dengue, Chagas disease and Yellow fever. The sampling approach was finalistic, and included the workers in a health district of Pernambuco, during the year 2000. A questionnaire was used to collect data on occupational and non-occupational risks, safety measures utilized, family history of auditory problems and health symptoms. Previous noise exposure history was also investigated, since noise can be a confounding factor for hearing loss. Hearing sensitivity and middle ear function were assessed by pure tone audiometry. RESULTS: Among those exposed to insecticides, 63.8% demonstrated a hearing loss. For the group of workers exposed to both noise and insecticides, hearing loss was observed in 66.7% of the cases. The median exposure time necessary to detect high-frequency losses was 3.4 years for workers exposed to both agents and 7.3 years for workers exposed to insecticides only. Hearing thresholds were poorest among workers exposed to both agents. Auditory damage for those with combined exposures to the two factors was more severe than the hearing losses observed among those exposed only to insecticides. CONCLUSIONS: There is evidence that exposure to insecticides was associated with peripheral sensorioneural hearing loss and that noise exposure can potentiate the ototoxic effects of insecticides. It is necessary to evaluate this possible association through epidemiological studies.     

Hearing loss in workers exposed to carbon disulfide and noise

Simultaneous exposure to carbon disulfide and noise may have a combined effect on hearing impairment. In this study we investigated hearing loss in 131 men with exposure to noise [80-91 A-weighted decibels; dB(A)] and CS(2) (1.6-20.1 ppm) in a viscose rayon plant. These men were compared with 105 men in the adhesive tape and electronic industries who were exposed to noise only and with 110 men employed in the administrative office of the rayon plant who were exposed to low noise and no CS(2). We conducted interviews to obtain sociodemographic information and exposure assessments, and we performed physical examinations, including hearing tests. Results showed that the prevalence of hearing loss of > 25 dB hearing loss (dBHL) in rayon workers (67.9%) was much higher than that in administrative workers (23.6%) and in the adhesive tape and electronic industrial workers (32.4%). Hearing loss occurred mainly for speech frequencies of 0.5, 1, and 2 kHz. When the CS(2) exposure was measured by the product of CS(2 )exposure level and employment years, the adjusted odds ratios of hearing loss of > 25 dBHL in rayon workers, compared with administrative workers, were 3.8 [95% confidence interval (CI), 1.5-9.4] for those with the exposure of 37-214 year-ppm, 14.2 (95% CI, 4.4-45.9) with 215-453 year-ppm exposure, and 70.3 (95% CI, 8.7-569.7) with exposure of > 453 year-ppm. The study suggests that CS(2) exposure enhances human hearing loss in a noisy environment and mainly affects hearing in lower frequencies.     

噪声接触工人脑干听觉诱发电位的探讨

采用丹麦产Keypoint肌电图诱发电位仪对 5 0名接触噪声工人 (接噪组 )及 2 0名正常对照者进行脑干听觉诱发电位 (BAEP)检测。结果显示 :接噪组波Ⅰ不出现率明显高于对照组 ,Ⅰ、Ⅲ、Ⅴ波潜伏期 (PL)及Ⅰ～Ⅲ、Ⅲ～Ⅴ波峰间潜伏期 (IPL)与对照组比较差异有显著性 (P <0 0 1) ,接噪组不同工龄BAEP各波PL及IPL改变与对照组比较差异显著 ,工龄 >10年组差异非常显著。上述结果提示 ,BAEP可预测噪声对听力的早期影响 ,BAEP检测可作为噪声职业危害的敏感指标。     

脉冲噪声对作业工人语言听力损伤的研究

目的 研究脉冲噪声作业工人语言听力损伤与噪声接触剂量之间关系,探索保护作业工人健康的噪声接触剂量限值.方法对508名脉冲噪声作业工人的调查数据,根据等能量观点,用寿命表原理的衍生方法建立语言听力损伤发病率与噪声接触剂量的关系模型.结果语言听力损伤累积发病率(Px)随着累积接触剂量(x)的增加而升高,两者存在下列关系:Ln y'=-12.319 4 5.252 1·Log x,式中,y'=Px/(1-Px).结论噪声强度、噪声接触时间影响语言听力损伤,若要保护95%的作业工人不发生语言听力损伤,噪声的累积接触剂量必须控制在60.953(万dB·h)以下.即相当于在120 dB脉冲噪声环境下,每天工作4 h的工人,工作年限不应超过4.41年.     

Effect of chronic and acute exposure to noise on physiological functions in man

Summary Physiological parameters have been compared in 75 normal healthy individuals exposed to occupational noise of 88–107 dB (A) (6–8h/day) for 10–15 years and in 36 normal non-exposed subjects. Blood pressure, both systolic (P<0.01) and diastolic (P<0.001), and heart rate (P<0.05) were found to be significantly higher in the exposed subjects. Irregularity in cardiac rhythm, both in amplitude and duration, was found in 18% of the exposed subjects as against 6% in the non-exposed group.Variation in the heart rate during acute noise exposure of 90 dB (A) has been shown to be related with the preponderance of tonicity of sympathetics and parasympathetics. Measurement of hand blood flow during the same exposure showed a lesser degree of vasoconstriction and a slower recovery rate in the exposed group. Altered observations in the exposed group could be attributed to changes in the mechanical property of blood vessels.