生产常用的安全帽一般应经过    试验。（ ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='27099' and id < 2247030 and id<>'2247030' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='27099' and id > 2247030 and id<>'2247030' order by id asc limit 5