Synonym: Standard Conditions = STP = s.c. = SPE STP
A specific combination of temperature and pressure:
...
The most popular alternative specification is provided by IUPAC which differs from SPE STP in in temperature reference: IUPAC Reference Temperature = 273.15 K = 0 °C = 32 °F = 491.67 °R.
It should not be confused with Normal Conditions (NTP) which is a different specification.
...