He's a 41-year-old mechanic at Kraft, a married father who likes to spend free time fixing old cars.
Yet when Hiller launched into a deadly rage after she was suspended on Thursday - allegedly killing two co-workers and injuring a third - police said Ciarlante acted with a level of courage most people will never know.
Police said he followed Hiller as she marched through the plant, using a radio to inform colleagues of Hiller's whereabouts and the best way to escape.
"I just followed her until the boys in blue came up," Ciarlante said humbly.
When the cops arrived, he gave them a step-by-step description of the plant, down to the number of phones inside offices where Hiller could have been hiding.
Homeland Security Chief Inspector Joseph Sullivan said Ciarlante "saved lives, saved time," by keeping tabs on Hiller, while risking his own life. "Pretty cool under fire," he said.
Sullivan and plenty of others, including friends and neighbors, called Ciarlante a hero.
He wanted no parts of it. "I'm no hero. I just did what anybody else would do," the skinny, scruffy-faced mechanic said last night outside his home in Bensalem.
As the words left his mouth, his voice caught and his eyes reddened, as an indescribable sadness fell across his face.
"I'm having a real hard time with this," he said softly. "A couple people I work with aren't here today."
Ciarlante said he was having a smoke break outside the Kraft building on Thursday when Hiller, clad in a Muslim headscarf and her Kraft uniform, walked by him, clutching her handgun.
He recognized Hiller as a fellow smoker and approached. "I said, 'You don't have to do this,' but she said, 'Get out of my way,' " Ciarlante said. "She was on a mission."
So he followed her, ducking every now and then behind pillars and walls while radioing her latest position. Eventually, police said, Hiller caught on and shot at him. "I got lucky," he said. "I just wanted to get people out there."
In his mind, he was just being helpful, a virtue his mother, Lorraine, instilled in all of her five boys.
"I always told them to do good in this life," Lorraine Ciarlante said. "I really wasn't surprised to hear what he did."
Neighbors recounted various good deeds Ciarlante is known for - changing a stranger's flat tire, helping neighbors with house repairs - while he waved off the praise.
"I'm just glad he's alive," said his 17-year-old son, David. "He's a hero in my heart."
