"Standard temperature and pressure" means a temperature of 20°C, equivalent to 68°F, and a pressure of one atmosphere.
N.H. Admin. Code § Env-Hw 104.49
(See Revision Note at chapter heading for Env-Hw 100) #9360, eff 1-28-09; renumbered by #10204 (from Env-Hw 104.48 )