The TLV-TWA for CO 2 , as listed by American Conference of Governmental Industrial Hygienists and by the Occupational Safety and Health Administration, is 5000 parts per million, or 0.5%.

• 正如美国政府工业卫生学者会议和职业安全和健康管理局所列出的，对于二氧化碳的TLV-TWA值是百万分之5000或0.；5%25。