Unfortunately we humans have become a race of shallow, thoracic-chest breathers, neglecting the primary muscle of respiration: the diaphragm.〔【出典】Hiragana Times, 1995年4月号◆【出版社】株式会社ヤック企画 〕"HT102070", "2547978"
The employer shall ensure that the concentration of carbonic dioxide gas in the air is kept at 1.5% or less in workshop in pits. However, this shall not apply to lifesaving or danger prevention work using air respirators, oxygen respirators or hose masks.〔【出典】日本法令外国語訳データベースシステム 〕