燃气热水器对室内空气污染的研究

为了探讨燃气热水器对室内空气污染的状况 ,我们对直排式、普通烟道式这两种燃气热水器在不同通风状态、不同燃烧时间室内一氧化碳 (CO)、二氧化碳 (CO2 )、二氧化氮 (NO2 )及甲醛的浓度进行了测定。结果发现 ,在不同通风状态下 ,直排式和普通烟道式燃气热水器燃烧后不同时间室内各污染物浓度均较燃烧前明显增高 ,并有递增趋势 ;室内各污染物除甲醛外均严重超标 ;直排式燃气热水器在关窗状态下使用室内污染物浓度最高 ,超标最严重 ;普通烟道式燃气热水器造成的污染明显低于直排式燃气热水器 ;通风能降低污染物浓度。上述结果表明 ,直排式和普通烟道式燃气热水器都能造成室内空气污染。     

使用燃气热水器对浴室内CO浓度的影响

使用燃气热水器,在液化石油气燃烧时产生的CO是浴室内空气污染的主要来源。在国内外的传媒报道中时有因不正确使用燃气热水器而造成CO中毒的事件刊载。为了解液化石油气燃烧对浴室空气造成的污染水平,寻找降低或消除其污染的措施,改善空气质量以保护人体健康,我们对使用燃气热水器造成的浴室CO浓度的变化规律及通风换气对其所造成的影响进行了研究。1 材料与方法1.1 选点 选择使用燃气热水器的8户住宅作为调查对象。     

统一公共场所室内空气中CO、CO2浓度标准值的可行性探讨

目的调查广州市公共场所室内CO、CO2浓度,并探讨公共场所室内CO、CO2浓度标准值统一的可行性.方法在广州市选择各类公共场所的822个监测点,将公共场所按<公共场所卫生标准>室内CO标准值分为第1类(≤5 mg/m3)、第2类(≤10mg/m3)、第3类(未作强制项目),按CO2标准值分为第1类(≤0.07%)、第Ⅱ类(≤0.10%)、第Ⅲ类(≤0.15%),监测室内空气中CO、CO2浓度,并进行分析.结果822个空气样本监测值显示,CO浓度(-x±s)为(2.76±1.41)mg/m3,第95百分位数(P95)为6.2mg/m3;CO2浓度(-x±s)为0.060%±-0.020%,P95为0.099%.CO、CO2监测值呈正偏态分布,即向污染较低的方向聚集;按CO浓度标准分级的3类公共场所空气中CO浓度差异无统计学意义(χ2=3.70,P=0.157);按CO2浓度标准分级的3类场所CO2浓度差异有统计学意义(χ2=35.266,P＜0.01);且第Ⅱ类场所CO2的污染比Ⅰ、Ⅲ类严重(P＜0.01).结论公共场所室内空气CO、CO2标准值分类的现实意义已减弱,采用合适的统一标准更具有现实可行性.     

北京某城区居室内空气污染现状及其影响因素

目的调查北京市某城区居室内空气污染现状,初步探讨影响室内空气中甲醛和氮氧化物(NOx)浓度的室内因素。方法在北京市西城区随机抽取463位居民进行室内环境状况问卷调查,从被调查者中随机抽取91户家庭,入户监测其室内空气中甲醛和NOx浓度。采用多元线性模型进行回归分析,筛选出与室内空气中甲醛、NOx浓度密切相关的室内因素。结果室内空气中甲醛日平均浓度为0.049mg/m3,超标率为13%,装修过的家庭卧室空气中甲醛浓度(0.058mg/m3)明显高于未装修家庭(0.034mg/m3),差异具有高度显著性(P<0.001);卧室和厨房空气中NOx日平均浓度分别为0.053和0.090mg/m3,超标率分别为9%和48%,其浓度差异具有高度显著性(P<0.001);装修与否、每月天然气用量、排烟渠道通向入选卧室空气中甲醛浓度回归方程;居室净高、吸烟与否入选卧室空气中NOx浓度回归方程;使用面积、居室净高、采样时间内开火做饭次数入选厨房空气中NOx浓度回归方程。结论该城区居民室内空气中甲醛和NOx污染较严重,家庭装修与卧室空气中甲醛浓度关系最密切,天然气燃烧是厨房空气中NOx和卧室空气中甲醛的重要来源,吸烟是卧室空气中NOx的重要来源之一。     

警惕无形杀手——一氧化碳

一氧化碳(分子式CO)俗称煤气。它是一种无色、无味、无臭(读作“秀”)的气体,几乎不溶于水。一氧化碳是含碳物质不完全燃烧时的产物,其与空气混合浓度达12.5%时有爆炸性。除工业生产外,家庭用的火炉,在冬、春季取暖时,由于烟囱堵塞、倒烟及门窗紧闭导致通风不良,均可储积大量一氧化碳;安装使用不当的(直排式)燃气热水器及燃烧不全的炭火锅、液化气火锅等也能产生大量一氧化碳。一氧化碳中毒是急诊常见病,严重时可危及病人生命。病例1:某单位门卫老张,因门卫室没有暖气,只好生蜂窝煤炉取暖。时已早春,天气乍暖还寒,用了一冬的烟囱内积满了灰…     

装甲车辆乘员血中碳氧血红蛋白含量估算分析

目的通过估算装甲车辆作业过程中乘员血中的碳氧血红蛋白含量,为车辆改进和人员防护提供依据。方法采用PGM 2000复合式电化学气体检测仪,连续测量车辆以20~50 km/h速度在混合路面上密闭行进120 min时舱内的CO浓度,计算CO时间加权平均浓度和短时间接触浓度,同时计算行进20、40、60、80、100和120 min时舱内的CO平均浓度,依据碳氧血红蛋白(COHb)与CO浓度、暴露时间的公式,估算乘员血中的COHb含量。结果驾驶舱的CO时间加权平均浓度为16.7 mg/m3,短时间接触浓度为95.6 mg/m3,作业舱的CO浓度时间加权平均浓度为13.8 mg/m3,短时间接触浓度为87.2 mg/m3,驾驶舱和作业舱的CO短时间接触浓度均超过了标准限值规定;驾驶员和作业舱乘员作业结束时血中的COHb含量分别为5.1%和4.3%,驾驶员血中的COHb含量超过了标准限值规定。结论应采取措施严格控制装甲车辆舱室内CO浓度。     

我国大气污染与儿童肺功能的关系

目的 描述我国主要的大气污染物(TSP、SO2、NOx)与儿童肺功能各指标[儿童用力肺活量(FVC)、1秒用力呼气容积(FEV1)、最大呼气中段流速(MMEF)]的相关关系.方法 收集整理国内1985-2006年1月公开发表的关于大气污染与儿童肺功能研究的文献,选择研究人群中包括7～15岁儿童,报告了当地大气质量的监测结果,肺功能测定过程采取了严格质量控制措施,并且结果以实测值均数表示的文献共11篇,分析我国城市主要大气污染物浓度与儿童FVC和FEV1的相关关系,并分别比较对男女儿童的影响.结果 最终入选的文献涉及我国7个城市的研究结果,其中,6个城市的研究发现大气污染严重的地区儿童的肺功能指标低于污染较轻的地区,且差异有统计学意义.上述研究中,大气中TSP平均浓度范围为0.084～0.835 mg/m3;SO2为0.013～0.929 mg/m3;NOx为0.044～0.229 mg/m3.相关分析发现研究地区大气的TSP和SO2浓度与儿童FVC和FEV1,NOx浓度与儿童的MMEF呈显著的负相关关系.儿童FVC与TSP浓度和SO2浓度的对数的相关系数分别为-0.797(t=-4.384,P=0.001)和-0.693(t=-4.190,P＜0.001);儿童FEV1与TSP浓度和SO2浓度的对数的相关系数分别为-0.886(t=-5.392,P=0.001)和-0.685(t=-4.101,P=0.001);儿童MMEF与NOx浓度的相关系数为-0.973(t=-5.993,P=0.027).分析还发现,随着大气TSP或SO2浓度的升高,女童FVC和FEV1的降低比男童多.结论 我国大气中TSP和SO2浓度能造成儿童大气道功能的下降,NOx浓度则主要影响儿童的小气道功能;与男童相比,女童肺功能更易受到大气污染物的影响.     

高层建筑地下室空气质量调查

目的了解高层建筑地下室的空气卫生状况。方法于2002年7月连续3d对某高层建筑地下室11个工作、生活房间进行空气的物理、化学及微生物指标检测。结果各检测点平均室温25.5℃;相对湿度较高,平均为78.7%;空气流通差,平均风速为0.057m/s,相对湿度与气温、气流均呈负相关(气温:r=-0.850,P<0.05;气流:r=-0.611,P<0.01);空气CO2浓度平均为0.06%;CO平均浓度为(0.967±0.287)mg/m3;甲醛平均浓度为0.060mg/m3;氨平均浓度为(0.456±0.374)mg/m3;耗氧量平均为(10.28±4.93)mg/m3,并且与甲醛、氨呈正相关(甲醛:r=0.606,P<0.05;氨:r=0.589,P<0.05),空气细菌数较少,细菌总数平均为(2.29±1.01)cfu/皿,链球菌为(3.54±1.78)cfu/皿。结论地下室各房间空气指标测定结果除个别检测点甲醛超标外,其余均符合Ⅱ类人防工程标准值要求。     

山西潞安某煤业有限公司煤层气发电建设项目职业病危害因素调查及防护效果预评价

目的 预防和控制煤层气发电过程中职业危害,保护劳动者的安全与健康.方法 开展现场职业卫生学调查与职业有害因素检测.结果 CO平均接触浓度为(4.34±0.06)mg/m3,NO2平均接触浓度(0.44±0.02) mg/m3,S02平均接触浓度(0.72-±0.01) mg/m3.噪声强度为84.8 ～92.8 dB (A),工种8h等效声级82.0 dB (A);频率计权振动加速度0.15m/s2;湿球黑球温度(WB GT)指数31.5℃;热辐射强度570 W/m2;控制室噪声强度73.5 dB (A),工频电场强度0.145kV/m;变压器室工频电场强度0.148 kV/m.结论 该煤层气发电工作场所空气中有害气体和物理因素危害检测结果均符合国家职业接触限值.噪声、高热环境、CO、NOx及硫化物是煤层气电站职业危害防护重点.     

家用燃料气态燃烧产物对室内空气污染的初步评估

目的 初步评估天然气、液化石油气和蜂窝煤的气态燃烧产物对室内空气污染的影响程度和特征.方法 在特别设计的3间实验房间内分别使用天然气、液化石油气和蜂窝煤在室内进行定量燃烧,同时根据国家标准方法采集空气样品并测定SO2、NO2、CO和甲醛的浓度,对其排放量和排放特征进行分析.结果 3种燃料的气态燃烧产物(SO2、NO2、CO、甲醛)中,均以CO和NO2的排放量最高.在日均用量下,蜂窝煤的CO和NO2排放量远高于天然气和液化石油气.使用蜂窝煤的家庭CO单位排放量高达30 136 mg/kg,明显高于液化石油气(8 725 mg/kg)和天然气(2 755 mg/kg);液化石油气的NO2单位排放量(42.69 mg/kg)则明显高于蜂窝煤(20.01 mg/kg)和天然气(11.87 mg/m3).在通风不良的室内,均可使室内CO和NO2浓度均超过GB/T 18883-2002<室内空气质量标准>.结论 厨房室内燃烧天然气或液化石油气,能造成CO和NO2的污染.     

Climate, traffic-related air pollutants, and asthma prevalence in middle-school children in taiwan

This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan.     

自贡市室内空气污染现状研究

采用现场调查方法,对自贡市不同燃料及建筑类型室内空气污染现状进行研究。结果表明燃煤户室内各污染物浓度高于燃气户,两者比值比二氧化硫（１４．８０）及硫化氢（７．６０）高。苯并（ａ）芘最大日平均值燃气户（６．９０μｇ／１００ｍ＾３）接近燃煤户（７．２５μｇ／１００ｍ＾３）的污染水平。由于受建筑类型的影响,楼房户厨房与卧室的浓度比值大于平房户,其中二氧化硫（３．８３）、苯并（ａ）芘（３．７１）、一氧化碳     

Occupational exposure to chain saw exhausts in logging operations

The composition of exhaust emissions from two-stroke chain saw engines was studied. The emissions of exhaust were sampled and analyzed under controlled laboratory experiments. The compounds sampled were those considered primarily responsible for acute health effects--hydrocarbons, aldehydes, nitrogen oxides and carbon monoxide. Exposure to tetramethyllead, dibromoethane and polycyclic aromatic hydrocarbons also was monitored. The results revealed no significant differences in the exhaust emissions from seven different chain saws. Heavily worn-out chain saws do not emit increased amounts of exhaust. A lean fuel-air mixture increases the emission of aldehydes and nitrogen oxides, whereas a rich mixture increases emission of carbon monoxide and hydrocarbons. Based on these new data on the composition of two-stroke chain saw exhaust emissions, operator exposure to chain saw exhaust was evaluated under various logging situations. Exposure measurements revealed no difference in average levels of exposure between logging in the presence or in the absence of snow. The felling operation, however, results in high exposure levels of short duration--especially when the operation is performed while there is deep snow on the ground. (This operation excludes limbing and bucking into lengths.) This is judged to be the main cause of the discomfort experienced by loggers. Average exposure levels for loggers engaged only in felling are twice those for cutters who also perform limbing, bucking and manual skidding of the timber, since these latter operations involve considerably lower exposure. Typical average levels of exposure are as follows: hydrocarbons, 20 mg/m3; benzene, 0.6 mg/m3; formaldehyde, 0.1 mg/m3; and carbon monoxide, 20 mg/m3.     

石油液化气燃烧对室内空气污染的研究

为探讨以石油液化气为燃料的大庆地区室内空气污染情况，以氮氧化物、一氧化碳及二氧化硫为检测指标，对该地区室内空气污染现状及其污染物的浓度变化规律进行了研究。     

Exposure of welders to fumes and gases in Dutch industries: summary of results

A study was made of the exposure of welders and cutters in Dutch industries to air pollution consisting of total particulate, chromium, nickel, copper, nitrogen oxides, ozone, carbon monoxide and other pollutants. Guidelines are given to help industrial hygienists to estimate the exposure of welders and cutters to chemical agents. The required reduction factors for exposure are given for various types of welding.     

南宁市25起急性CO中毒事件分析

目的通过分析急性一氧化碳(CO)中毒病例发病特点,探讨CO中毒防护对策。方法对2006—2011年1月南宁市发生的急性CO中毒事件的资料进行整理分析。结果 2006—2011年1月南宁市发生急性CO中毒25起,中毒病例97人,死亡10人,男性多于女性,中毒年龄以20～30岁居多(71.1%),冬春季高发,中毒原因以燃气热水器使用不当为主(78.3%)。结论必须加强冬春季节室内通风换气和燃气热水器的正确安装和使用,以及CO中毒相关知识的培训,增强人们自我防范CO中毒的安全意识,防止CO中毒。     

Hygienic evaluation of direct heating of the air delivered to the shaft

The paper gives the results of exploring a test pre-heating system for the air (APHS) delivered to the shaft. The system has been first used in the Urals. The supply air is heated by burning natural gas in the air current. The APHS system with a RG air heater (000 "Gas-Engineering") is equipped in addition to the existing heaters to enhance heat supply reliability in northern conditions. The data of the studies show that in all periods of the heating season (interseason, moderate frosts, the coldest month), the concentrations of hazardous substances, such as nitric oxides, nitric dioxide, sulfur dioxide, carbon dioxide, benz(a)pyrene, solid aerosol in the shaft-delivered air, do not exceed those given in the existing regulation provided that the design operating conditions are met. With the maximum gas consumption, the coldest month only was marked by the nitric dioxide content being greater than the standard values, causing the maximum projected natural gas consumption to be lower in the APHS system. The air level of nitric dioxide proved to be a major hygiene indicator while using this air heater.     

Carbon monoxide exposure in households in Ciudad Juárez, México

This study assessed exposure to carbon monoxide from gas and wood heater emissions in a sample of 64 households in peri-urban residential areas in Ciudad Juárez, Chihuahua, México. Indoor and outdoor carbon monoxide concentrations and temperatures were monitored for a continuous period of 1 week at 1 and 6-min intervals, respectively. The moving average carbon monoxide concentrations were compared to the World Health Organization (WHO) standards for carbon monoxide. Sixty-seven percent of households with gas heaters and 60% of households with wood heaters exceeded a health-based standard at some point during the monitoring. The difference between indoor and outdoor temperatures was modestly correlated with average carbon monoxide exposure (r=0.35, p-value <0.01). Heater type may be a stronger determinant of exposure, as households with a particular heater model (the El Sol FM-210) were significantly more likely to be among the more highly exposed households (odds ratio of 4.8, p-value of 0.02). A variety of health effects were pooled and found at elevated frequency in the households that exceeded the 8-h standard of 9 ppm (odds ratio=5.1, p-value=0.031). These results highlight the need for further efforts to identify and mitigate potentially hazardous carbon monoxide exposures, particularly in moderate-income countries with cooler climates.     

An unusual case of carbon monoxide poisoning.

Carbon monoxide, a gas originating from incomplete combustion of carbon-based fuels, is an important cause of human deaths. In this paper, we describe an unusual carbon monoxide poisoning in a dwelling without obvious sources of combustion gases, for which two adults had to be treated in a hyperbaric chamber. Carbon monoxide readings were taken in the house and in the neighboring homes. Methane gas and nitrogen oxide levels were also monitored in the house air. Soil samples were collected around the house and tested for hydrocarbon residues. The investigation revealed the presence of a pocket of carbon monoxide under the foundation of the house. The first readings revealed carbon monoxide levels of 500 ppm in the basement. The contamination lasted for a week. The investigation indicated that the probable source of contamination was the use of explosives at a nearby rain sewer construction site. The use of explosives in a residential area can constitute a major source of carbon monoxide for the neighboring populations. This must be investigated, and public health authorities, primary-care physicians, governmental authorities, and users and manufacturers of explosives must be made aware of this problem.     

低浓度一氧化碳和氮氧化物对神经行为的影响

氮氧化物和一氧化碳是汽车尾气的主要气态成分，也是城市空气的主要污染物。本文从动物实验和流行病学两个方面，综述了国内外关于大气中低浓度氮氧化物和一氧化碳对神经行为功能及行为致畸作用的影响，包括毒物单独和联合作用及其毒作用机制，为进一步的研究提示方向。