"Dissolved gases"@en . . "SDN:P03::C015" . "This group incorporates dissolved gas concentrations and/or saturations, excluding: Gases that are incorporated into the water column through chemical reaction and quantified as the products of the reaction, such as ammonia and carbon dioxide. Gases that belong to other chemical-type APGs. For example, methane parameters are placed in the Hydrocarbons APG and not Dissolved Gases. Gases are defined as substances with a boiling point below 50 °C at atmospheric pressure (terrestrial conditions extreme limit). The group also includes: Parameters collected by instruments making in-situ measurements of dissolved gas concentration, such as oxygen membrane current and temperature. Parameters required for data standardisation, such as oxygen fixation temperature. Parameters required for the interpretation of gas concentration parameters, such as the temperature and pressure at which the concentration has been calculated if these differ from the in-situ conditions for the sample. This APG should represents dissolved gases that do not fit in any other category and consequently its contents should be periodically reviewed to see if further classes need to be specified."@en . .