Ayers, who has served as head of the Philadelphia Fire Department since December 2004, will retire in June 2014.
Ayers became a Philadelphia firefighter in 1974 and served in every rank within the department, from Lieutenant to Deputy Commissioner, before being appointed Fire Commissioner by Philadelphia Mayor John Street.
He was re-appointed by current Mayor Michael Nutter in 2008.
"40 years is a lot of time," Ayers said on Thursday.
As Fire Commissioner, he oversees 2,400 uniformed firefighters and all the operations of the Philadelphia Fire Department, the fifth largest fire department in the United States.
Ayers said his greatest joy is cutting the number of fire deaths and overall fires in the city. His greatest disappointment is losing seven firefighters in the line of duty during his tenure.
The commissioner has had his battles with the firefighter's union over cost-cutting measures like rolling brown-outs at various stations across the city.
However, the five-year battle over pay raises is over. The rank-and-file will be getting an average of $5,000 in retroactive pay over the next two pay periods.
"It's been tough," Ayers said. "The union should protect the members, and I have an obligation to protect the members."
Ayers and his wife, Annette, live in the Andorra section of Philadelphia and have six children.
"I'm mentally prepared for retirement," Ayers said. "As far as my life is concerned, I'm healthy, I'm strong. That's a blessing."
Ayers said he will continue his devotion to public service, including the American Red Cross and community efforts to prevent fires.