Final answer:
When cleaning a pleated paper-type air filter element, the air gun should be held away from the outside of the filter element to avoid causing damage.
Step-by-step explanation:
When cleaning a pleated paper-type air filter element, the air gun should be held away from the outside of the air filter element. Holding the air gun directly against the filter element or against the inside of the filter element can cause damage to the filter and reduce its effectiveness.