DENVER -- Members of the sheriff's bomb squad who sparked a 1,313-acre grassfire by detonating a device on one of the windiest day of the month will not face criminal charges, the Arapahoe County Sheriff's Office said Friday.

The bomb squad was training near the 36000 block of East Quincy Avenue on Feb. 20 when flames from the detonation spread, creating a grass fire that prompted the vacuation of one house.

No homes were burned and no one was hurt.

However, an internal investigation determined that the bomb squad did not establish adequate safety measures, did not implement appropriate precautionary measures and did not follow established training protocols, Arapahoe County Sheriff Grayson Robinson said.

Robinson said the grass fire was caused by the detonation of expired OC pepper spray canisters which were no longer usable, so the detonation was an acceptable and standard destruction practice.

The internal investigation also determined that the amount of land burned was larger than the 200 acres originally estimated. The Arapahoe County Assessors Office, utilizing GPS technology, determined that 1,313 acres burned.

The deputies on scene were not able to contain the grass fire and called the Bennett Fire Protection District for help. Byers Fire, Strasburg Fire, Deer Trail Fire, Sable Altura Fire, Rattlesnake Fire, Cunningham Fire and the heavy equipment crews from Arapahoe County Public Works all worked on containing the blaze within three hours.

The actions of the bomb squad are "currently subject to the internal affairs processes of the Arapahoe County Sheriff’s Office," Robinson said.

Robinson if the investigation found the deputies in violation of the policies and procedures of the Arapahoe County Sheriff’s Office, they will face "significant consequences," but he did not say what kind of consequences, citing personnel privacy law.

The training occurred after the National Weather Service issued Red Flag Warning. A Red Flag Warning means that weather conditions, specifically low humidity and high wind, make the day ripe for the rapid spread of any fire.

The 24/7 Weather Center recorded wind gusts up to 60 mph with sustained winds of 20 mph.

"Why would anybody ever have anything to do with any kind of flammables on day that's that windy?" said Robert Harrington, who had to evacuate. "With winds like that, the fire was probably spreading faster than a normal person could run."