Final answer:
Woodwork or other combustibles should not be placed within 36 inches of a fireplace opening to prevent the risk of fire.
Step-by-step explanation:
In order to prevent the risk of fire, woodwork or other combustibles should not be placed within 36 inches of a fireplace opening. This safety measure is important because woodwork and other combustibles can easily catch fire when exposed to high temperatures or sparks from the fireplace.