Progress was slow and new releases came courtesy of voices38.
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.
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The Guardian’s Jenna Amatulli talks to Rolling Stone’s Nikki McCann Ramírez about Trump’s claims, the Democrats’ rebuttal, and how the speech will land with a divided nation