"if the battery in a mechanical mod over-discharges and the device doesn't contain enough air holes to allow the battery to vent, there is a risk of explosion." http://lm360.us/Blatnick-sister-of-Beston-from-Prigny?Svayfathe=176
poor air quality is not unique to the uk or europe. more than 90% of people around the world breathe dangerous levels of air pollution, according to the .