<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区

          Agency sets new rules for mine safety

          Updated: 2011-08-22 07:52

          By Yan Jie (China Daily)

            Comments() Print Mail Large Medium  Small 分享按鈕 0

          BEIJING - China's top workplace safety regulator is introducing national standards for safety technologies used in the country's accident-plagued coal mines.

          A set of four standards on polymeric materials used for coal mining safety will take effect on Dec 1, according to the State Administration of Work Safety (SAWS).

          The standards are related to the prevention of coal mine accidents, including methane gas blasts, underground floods and shaft collapses, by using high-technology polymeric materials, Jiang Zhimin, the secretary-general of the China National Coal Association, said on Sunday at a conference to introduce the standards.

          Polymeric materials, a group of chemical compounds that are in liquid or foam states, are mainly used for four functions that are covered by the standards: water shut-off, filling and sealing of mine structures, ventilation sealing and consolidation of coal and rock.

          The four functions are related to the prevention of mine floods, shaft collapses and fire accidents.

          Introduced in China from Western countries in the 1970s, these chemicals have found widespread use in domestic coal mines in the past five years.

          As of the end of 2010, there were more than 30 producers of these polymeric materials in China, employing nearly 3,000 workers and professionals, said Zhang Nong, a mine expert from the China University of Mining and Technology.

          Sales of the materials totaled about 1.2 billion yuan ($188 million) nationwide in 2010.

          However, the absence of national standards for these chemicals has aroused concern at some mines.

          "The number of producers has increased in recent years," said Ni Jianming, a senior engineer with the Huaibei Coal Mining Group Co Ltd. "But the quality of the products is mixed and quality problems have caused some accidents."

          Producers of the polymeric materials must ensure that there are no safety flaws in their products, said Huang Yi, spokesman for SAWS.

          "The administration will perfect the system of coal mine safety standards," he said.

          主站蜘蛛池模板: 国产精品∧v在线观看| 好大好硬好深好爽想要20p| 亚洲国产精品毛片在线看| 亚洲精品电影院| 漂亮的保姆hd完整版免费韩国 | 国产亚洲日韩在线aaaa| 国产极品粉嫩尤物一线天| 国产精品激情av在线播放| 蜜臀av一区二区三区人妻在线| 亚洲人成网站18禁止无码| 国产又黄又猛又粗又爽的a片动漫| japan黑人极大黑炮| 国产乱来乱子视频| 成人午夜福利视频一区二区| 国产精品亚洲精品日韩已满十八小| 亚洲欧美电影在线一区二区| 欧美gv在线| 久久青青草原亚洲AV无码麻豆| 少妇被粗大的猛进出69影院| 琪琪午夜成人理论福利片| 国产偷窥熟女高潮精品视频| 久一在线视频| 亚洲精品综合网二三区| 中文在线√天堂| 精品人妻av综合一区二区| 国产精品无码2021在线观看| 色综合久久精品中文字幕| 国产超高清麻豆精品传媒麻豆精品| 欧美性猛交xxxx免费看| 俺来也俺去啦最新在线| 亚欧洲乱码视频在线专区| 久久99精品久久久学生| 亚洲欧美不卡高清在线| 97久久精品无码一区二区| 米奇777超碰欧美日韩亚洲| 成在人线AV无码免观看| 天堂资源在线| 亚洲欧美综合在线天堂| 国产性天天综合网| 国产成人一区二区三区免费| 国产一区二区精品高清在线观看 |