Gas & Fuel第 65 / 110 题
A newly installed natural-gas piping system is pressure tested before being placed in service. A common test is 3 psi (or 1.5 times working pressure, whichever is greater) held for a set duration. For low-pressure residential piping, what is a typical minimum test pressure and duration?
a.3 psi for at least 10 minutes with no pressure drop
b.1 psi for 5 minutes
c.2 psi for 8 minutes
d.10 psi for 30 seconds
解析
A common acceptance test for residential gas piping is 3 psi held for at least 10 minutes (some jurisdictions require longer) with no observable pressure drop on the gauge. The test isolates appliances and uses air or inert gas, never the fuel gas itself. Any drop indicates a leak that must be found and repaired before gas is introduced.
法律依据: IFGC §406.4免费刷完整 110 道题库 — 无需注册。
同考点相关题目
- Appliance venting is classified by category. A Category I appliance is best described as which of the following?
- A high-efficiency condensing furnace exhausts cool, wet flue gas under positive pressure. What venting category and material are appropriate?
- Corrugated stainless steel tubing (CSST) must be electrically bonded to reduce the risk of arcing from a lightning-induced surge. Where is the bonding clamp attached?
- During a gas pressure test, appliances and their regulators must be protected. What is the correct way to include or exclude appliances during a 10 psi test?
- A propane branch must deliver a 75,000 BTU/hr appliance at a longest length of 40 ft. Propane is 2,500 BTU/ft^3. The 40 ft table lists 1/2 in = 45 cfh and 3/4 in = 95 cfh. What is the required cfh and minimum pipe size?
- A hospital adds a nitrogen line for surgical tools alongside oxygen and medical air. What single feature most prevents a fatal mix-up of these medical/industrial gases at the outlet?