Outdoors : Location outside of any building or structure or locations under a roof, weather shelter, or canopy provided this area is not enclosed on more than two sides
NFPA 50A Standard for Gaseous Hydrogen Systems at Consumer Sites, 1999 ed. http://www.hydrogenandfuelcellsafety.info/resource s/workshops/04apr/csRivkin_apr04.pdf, (Std: Site Gaseous Hydrogen Sys at Consumer Sites - Amer) {206 NFC}