Coast Guard Regulations (46 CFR) require that the design pressure of an economizer integral with the boiler and connected to the boiler drum without intervening stop valves shall be at least equal to __________.

Correct Answer: Option C — 110% of the drum safety valves highest set pressure

Title 46 CFR requires economizers connected directly to the boiler drum without intervening valves to possess a design pressure at least 110 percent of the drum safety valves' highest set pressure, ensuring the economizer safely withstands maximum possible system pressure spikes.