The design working pressure and safety factor required by NFPA 58 for hose used with propane dispenser is:

• A. 150 psi 3:1
• B. 350 psi 5:1
• C. 500 psi 4:1
• D. 100 psi 2:1

Answer: (B)

NFPA 58 specifies how hoses used at propane dispensers must be built, including both the pressure they are designed to carry in normal use and the safety margin to prevent failure. For hoses at dispensers, the design working pressure is 350 psi, and the required safety factor is 5:1. That means the hose must be rated so its burst pressure is at least about 1,750 psi. This generous margin helps the hose withstand pressure surges and any minor abuse during dispensing, reducing the risk of rupture. Other options propose different working pressures or safety factors that do not align with NFPA 58’s requirements for propane dispenser hoses.