Syd Myers, a NASA Armstrong Flight Research Center confined space supervisor for a drill at NASA Armstrong Flight Research Center’s Building 703 in Palmdale, California, observes U.S. Air Force Plan 42 Fire Department responders extract a mannequin from a confined space as part of an emergency exercise.

Air Force Plant 42 Fire Department responder Alfonzo Ortega, bottom, hands Doug Mendez a gas meter to test the air in a confined space during an exercise at NASA Armstrong Flight Research Center's Building 703 in Palmdale, California. Dale McCoy, Armstrong confined space co-program manager, observers.

Air Force Plant 42 Fire Department responders Doug Mendez and Alfonzo Ortega test the air in a confined space with a gas meter during an exercise at NASA Armstrong Flight Research Center's Building 703 in Palmdale, California. Dale McCoy, Armstrong confined space co-program manager, observers.

Syd Myers, a NASA Armstrong Flight Research Center confined space supervisor for a drill at NASA Armstrong Flight Research Center’s Building 703 in Palmdale, California, called 9-1-1 to begin the exercise. Myers continued to update responders how the situation was evolving until help arrived.

U.S. Air Force Plant 42 Fire Department responders carry out the mannequin to an emergency vehicle during an emergency exercise at NASA Armstrong Flight Research Center's Building 703 in Palmdale, California. Responders included, from left, Kent Courter, Doug Mendez, Alfonzo Ortega, Cedric Willis, Tyler Lippens and Ricky Gimmestad.

A mannequin is used to simulate a worker who has collapsed and come free from a harness intended to extricate the worker in case of emergency as part of a confined spaces training at NASA Armstrong Flight Research Center’s Building 703 in Palmdale, California.