⚠ Indicative tool only. Source: OIML R 85-1 & 2, Edition 2008, the current edition (it supersedes the 1998 edition; confirmed current against multiple national standards bodies at the time of writing). This is an international recommendation — individual countries implement it through their own national legal metrology regulations, which may add, tighten, or modify requirements (particularly the rated-temperature bands in Table 1, marked in the standard itself as decided by the national authority, and the subsequent-verification interval, which R 85 recommends at 2 years but does not mandate). Confirm against the regulation actually in force where the tank is located.