Washington, DC – Fentanyl is a synthetic opioid pain reliever. Because a small amount of fentanyl can be deadly, emergency responders and hazmat teams are concerned about their potential exposure while responding to incidents at mixing houses, pill factories, or in makeshift laboratories found in apartments, hotels, houses, garages, and storage facilities. They are also concerned with exposures from remnants of laboratories that have been dumped illegally and possible fentanyl releases in correctional facilities.