1. Start with safety when the situation is urgent
A directory search should never delay an emergency response. Leave the building and contact the appropriate utility or emergency service from a safe location for a suspected gas leak, carbon-monoxide alarm, fire, smoke, or another immediate hazard.
For equipment failures that are uncomfortable but not immediately dangerous, use the directory to identify contractors that publicly state the relevant service. Emergency availability can change by day, time, location, and staffing, so always confirm it by phone.