Carbon dioxide equivalent of carbon dioxide. Equivalent (e) is the concentration of that would cause the same level of radiative forcing as a given type and concentration of greenhouse gas. Examples of such greenhouse gases are methane, perfluorocarbons, and nitrous oxide. e is expressed as parts per million by volume, ppmv. Carbon dioxide equivalent Carbon dioxide equivalent (CDE) and equivalent carbon dioxide (e and eq) are two related but distinct measures for describing how much global warming a given type and amount of greenhouse gas may cause, using the functionally equivalent amount or concentration of carbon dioxide () as the reference. Carbon dioxide
Nitrous oxide and retains adequate mental faculties to respond to questions and instructions from the dentist. Inhalation of nitrous oxide is used frequently to relieve pain associated with childbirth, trauma, oral surgery, and acute coronary syndrome (includes heart attacks). Its use during labour has been shown to be a safe and effective aid for birthing women. Its use for acute coronary syndrome is of unknown benefit. In Britain and Canada, Entonox and Nitronox are used commonly by ambulance crews (including unregistered practitioners) as a rapid and highly effective analgesic gas. 50% nitrous oxide can be considered for use by trained non-professional first