Twentymile achieved a safety record of 1.03 for 2014 with 777,868 hours worked during the year and is being honoured for a third consecutive year for outstanding safety performance.

Peabody said the employees at Twentymile helped drive the best global safety results in the company’s 132-year history.

Twentymile received the President's Award for Safety five times and holds the record for the recognition of outstanding safety performance among Peabody's underground mines, having previously been recognised for the best underground safety performance in 2005, 2010, 2012 and 2013.

"Twentymile has earned its reputation as the state's largest coal mine that is perennially among the safest in the industry,” Peabody Energy, Americas president Kemal Williamson said.

“To consistently achieve results of this calibre, our employees must focus on safety each and every day. Every miner deserves to return home safely at the end of their shift, and I am very proud of their achievement and commitment to safety.”

The company said strong communication, looking out for one another and innovative ideas were “hallmarks” of the safety culture at Twentymile.

Pat Sollars, general manager of operations at Twentymile, said the Colorado team valued everyone's safety and was dedicated to best practice in safety performance.

“We constantly seek innovative solutions to eliminate risk, and for Twentymile employees, safety is not a statistic, it is a way of life,” he said.

Sollars also pointed to Twentymile Mine's contribution to the region in terms of economic impact and community engagement.

“While our safety record is our proudest accomplishment, we are also proud of our role in northwest Colorado in terms of jobs and support of projects in our communities,” said Sollars.

Twentymile employs 335 full-time workers and annually injects more than $182 million into the regional economy.

Globally, Peabody achieved a 1.44 safety incidence rate per 200,000 hours worked.