密闭空间的冷空气供应可行性:地下避难所替代案例研究
Lincan Yan1, Dave S Yantek1, Cory R DeGennaro1
1CDC/NIOSH, Pittsburgh, PA 15236.
概括
这项研究表明,冷空气供应有效地保持在狭窄的空间安全的氧气和二氧化碳水平,满足联邦法规的地下避难所替代品. 这些发现支持使用冷空气在这样的环境中确保可呼吸的空气.
科学领域:
- 职业安全与健康问题 职业安全与健康问题
- 环境工程 环境工程
- 矿业安全 矿业安全
背景情况:
- 像地下避难所 (RAs) 这样的封闭空间需要可靠的可呼吸空气源.
- 联邦法规要求RAs在96小时内特定氧气 (18.523%) 和二氧化碳 (<1%) 度.
- 现有的RA空气供应方法需要评估,以确保合规性和安全性.
研究的目的:
- 评估冷却式空气供应系统在模拟避难选择中维持可呼吸空气质量的有效性.
- 为了确定冷空气是否可以在模拟的人类居住下维持所需的氧气和二氧化碳水平96小时.
- 为地下避难所替代品和其他狭窄空间提供支持使用冷空气的数据.
主要方法:
- 在一个密封的运输集装箱中进行了两次96小时的测试,模拟了RA.
- 一个气吸烟器通过消耗氧气并产生二氧化碳来模拟人类的呼吸.
- 将冷空气输入容器,并调整了燃烧速率,以模拟两个不同速率下的21人的氧气消耗.
主要成果:
- 在这两次96小时的测试中,氧气水平始终保持在21%至23%之间.
- 二氧化碳度保持在1%以下,具体在0.2%和0.45%之间.
- 低温空气供应成功满足了模拟RA中可呼吸空气的联邦监管要求.
结论:
- 低温空气供应是一种可行且有效的方法,可以在狭窄的空间中提供可呼吸的空气,如地下避难所替代品.
- 测试系统可靠地在长时间内保持氧气和二氧化碳水平在法规限制内.
- 这项技术可以提高地下采矿和其他危险的封闭环境中人员的安全性.
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