Operators doing the inspection should pass regular eye-sight checks, with spectacles if worn, and be allowed frequent breaks from inspection.

进行目视检查的操作人员要定期进行视力检查，可以戴眼镜，并允许经常间断检查。

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Manufacture and inspection for sight glass shall be in accordance with HGJ501-502-86 standard.

制造、检测标准：参照“HGJ501-502-86压力容器视镜”设计制造和验收。

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At first glance, the four Japanese men at the booth could have been doing anything on their MacBook Pros -- there wasn't a musical instrument in sight -- but upon closer inspection, they each appeared to be holding identical loupe-like devices, connected to each laptop via USB.

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Hot on the heels of its look at what's now called the Xperia T, Mobile-review has given the entry-level Xperia J a full inspection without even the hint of a press release in sight.

ENGADGET: Sony Xperia J gets a pre-unveiling hands-on, suggests we'll get exactly what we pay for