A boiler has a steam delivery capacity of 100,000 pounds per hour, and is equipped with four steam atomizing burners. If the load range of the burners is 4 to 1, this means that __________.

Correct Answer: Option B — the boiler may be operated down to 25,000 pounds per hour without securing any burners

A 4-to-1 turndown ratio means each burner can modulate from maximum capacity down to 25% of that rating individually. For a 100,000 lb/hr boiler with four burners, total minimum output without securing a burner is 25,000 lb/hr, as the collective turndown applies across all active units.