9/11/14-JOINT BASE SAN ANTONIO-RANDOLPH, Texas –
During the hottest months of the year, computer users throughout Joint Base San Antonio receive email messages from the 502nd Air Base Wing command post that play an important role in mission safety and efficiency.
The messages let supervisors know it's time to protect their Airmen and other workers from the effects of oppressive heat by announcing the wet bulb globe temperature index, a combination of temperature measurements that factor dry air temperature, air movement, relative humidity and radiant heating.
"It's all done to protect the workers," Maj. Alfred Doby, 359th Aerospace-Medicine Squadron bioenvironmental engineering flight commander, said. "It ensures that supervisors are providing them with the proper rest cycles to combat heat illness and heat stroke."
Five "flag conditions" are based on the WBGT index, Airman 1st Class Tyler Brantley, 359th AMDS bioenvironmental engineering technician, said.
Flag conditions, displayed in five colors, range from white for a WBGT of 78 to 81.9 degrees to black for a WBGT of 90 degrees or more, but messages are not typically relayed to computer users until the flag condition is red, or 88 to 89.9 degrees, he said. Other flag conditions are green, 82 to 84.9 degrees, and yellow, 85 to 87.9 degrees.
A device called a thermal environment monitor, which is placed in an unshaded location behind the JBSA-Randolph Medical Clinic at the beginning of the day, measures the WBGT, Brantley said. The monitor includes three temperature elements - a white "wet bulb" that measures humidity and air movement, a black dry "globe" that measures radiant heat from the sun and a shielded thermometer that records ambient temperature.
"It's all done through a digital medium," he said. "In addition, the new device we use does not require water."
Readings are relayed to a remote display inside the bioenvironmental engineering flight and are announced to the JBSA command post when they reach the yellow flag WBGT, Brantley said.
At JBSA, flag conditions are sent via email messages from the command post, but some installations also use actual flags, Giant Voice notifications, and cellphone texts and voice messages, Doby said. Examples are Air Combat Command and Pacific Air Forces bases.
"That's ultimately where we want to be," he said. "They're pushing the envelope because of their missions."
The flag conditions are especially important for Airmen and civilians who are subjected to heat on a regular basis, Brantley said. They include people who work in shops on the flightlines, security forces, firefighters and groundskeepers, as well as Airmen who take part in physical training and others who exercise outdoors.
Supervisors monitor the different flag conditions so they can implement work/rest cycles and water intake based on guidance in Air Force Pamphlet 48-151, he said. Taking these measures helps prevent heat-related illnesses.