CSLB Class B General Contractor's License Practice Exam

What pressure level is considered standing pressure in the scenario provided?

1. 80 psi

2. 100 psi

3. 120 psi

4. 150 psi

The correct answer is: 120 psi

Standing pressure refers to the pressure within a system that is not actively engaging in any fluid flow, often measured in pounds per square inch (psi). In many plumbing and construction contexts, a standing pressure of 120 psi is recognized as a typical upper limit for residential water pressure systems. This level is generally considered adequate for daily residential use, providing sufficient pressure for fixtures without risk of damage or failure in the system. When assessing other pressure levels, those below 120 psi might indicate insufficient pressure for optimal function in certain applications, while pressures considerably above this level could pose risks such as leaks or bursts in pipes, fixtures, or appliances. Hence, 120 psi represents a balanced and manageable standing pressure for practical applications, making it the correct and most relevant choice in this scenario.