I read today that the FAA has extended the timeline in which it will be inspecting all charter operations specifications section A008 for compliance with operational control requirements.
We have three sizes of volumetric flasks to choose from: 100, 250 and 500 milliliters and they feature a single etched line or graduation to denote the fill-to-line at the chosen volume. Each size flask is specifically made for preparing solutions that correspond to its nominal value. For example, a 250 ml volumetric flask is the appropriate choice only when preparing a solution with a total volume of 250 ml.
Usually, the term fl oz refers to the US customary fluid ounce with a volume of 29.5735295625 ml [1], but getting 2.5 fl oz in ml may also be related to the US fluid ounce for food labelling, defined as 30 ml [2]. In the UK, there is only one liquid ounce of 28.4130625 milliliters [3].