关于紫外线治疗时的安全防护措施，不必要的是（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25668' and id < 2157254 and id<>'2157254' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25668' and id > 2157254 and id<>'2157254' order by id asc limit 5