3 ms·
1000 ppm is about where cognitive impairment starts, and that much or higher is commonly found in classrooms. If the outdoor ppm keeps going up, it only stands
by wing-_-nuts 5y ago
1000 ppm is about where cognitive impairment starts, and that much or higher is commonly found in classrooms. If the outdoor ppm keeps going up, it only stands to reason the indoor level will as well.