Loss to steam boilers, pipes, engines, and turbines caused by equipment is not covered unless:

• A. Gases or fuel exploded within the furnace, flues, or passages of a fired vessel
• B. The loss is covered by a separate policy
• C. The loss is due to a natural disaster
• D. The loss is due to vandalism

Answer: (A)

In boiler and machinery coverage, losses that happen to steam boilers, pipes, engines, and turbines are generally excluded if they’re caused by the equipment itself. An exception exists, though: if gases or fuel explode within the furnace, flues, or passages of a fired vessel, that internal explosion is a covered peril. In other words, when the explosion originates inside the equipment’s combustion area, the policy provides coverage for the resulting damage. This is why the internal-explosion scenario is the correct condition to make the loss covered. Other options—coverage under a separate policy, natural disasters, or vandalism—don’t trigger this specific exception.