"But I'm going to tell you it is harder to be a parent than to be a space shuttle commander," she laughs.
Optical-based smoke alarms use light instead. They are slightly better at detecting the large smoke particles created by slow, smouldering fires. When such particles enter a chamber in the device, they scatter light from a small light source, which is then picked up by a photoelectric sensor.
。关于这个话题，51吃瓜提供了深入分析
Save designs as templates for your team to use，这一点在safew官方版本下载中也有详细论述
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