BS 7461-1991 Specification for electrically operated automatic gas shut-off valves fitted with throuBS 7461-1991 Specification for electrically operated automatic gas shut-off valves fitted with throughput adjusters, proof of closure switches
部份国外标准涉及版权问题,所以全部国外标准于2013年02月,全部删除!相关页面仅提供参考消息。