Refers to the organs used in breathing such as the nose, throat, larynx, trachea, bronchi, and lungs. Your body uses this system to take in oxygen from the air and expel carbon dioxide. Respiration - is the act of inhaling and exhaling. In others words, breathing. Additional Info: The term pulmonary is used to refer to processes or conditions involving the lungs. For example, pulmonary edema is an abnormal buildup of fluid in the lungs. MSDS Relevance: Exposure to certain chemicals can result in irritation or damage to the respiratory system. Always read the MSDS to determine the safe working limits (PEL and TWA values) and to See: What kind of personal protective equipment (PPE) is suggested. Avoid exposure to dusts, fumes and vapors. Respirators are pieces of Personal Protective Equipment (PPE) that can help protect your respiratory system from exposure to hazardous chemicals. MSDS's may call for such PPE if appropriate engineering controls such as fume hoods are not available. See also: Asthma, Emphysema, Respirator