Lead mechanic Matt Deane and re-fueler Mick Gomme survived the incident with nothing more than bruising after Heidfeld ploughed into them during a pit stop.
"What happened in the pit stop has never happened to me before and I was pretty afraid for the mechanics," Heidfeld said.
"Luckily they are fine and that is the most important thing."
The German driver was called into the pits because of a clutch problem on his bar but was unable to stop as he approached his crew.
"It's not a problem we have had before but we noticed something wrong with the clutch and at the pit stop it didn't work at all so the car just kept pushing whilst stuck in first gear," he said.
Team boss Eddie Jordan said he was relieved the two pit crew were not seriously hurt.
"I'm glad to see that the guys who got run over are safe and in good shape," he said.
Heidfeld tried to re-join the race after the incident but rolled to a halt as soon as he left the pit lane once it was clear the clutch problem had not been fixed.
Heidfeld's team mate Giorgio Pantano finished his first Grand prix in 14th position, two laps behind race winner Michael Schumacher.
"I enjoyed my first Grand Prix and am very glad we made it to the end," the Italian said.
"I think it isn't too bad for our first race. Finishing the race was my target and I did it."
