The accident happened around 2:30 p.m. at New York Avenue and Congress Street in Jersey City.
According to authorities, a man had just finished doing refrigeration work at a deli on New York Avenue. He placed his equipment and a tank of refrigerant back in his car and it exploded.
Officials said the car contained three tanks and investigators are trying to determine which one caused the explosion.
The 40-year-old man putting the tank in the car sustained serious blast injuries to the head and chest, officials said. He is guarded condition, officials said.
Another man walking by at the time was also injured. He sustained minor facial injuries is in stable condition.
They were both taken to Jersey City Medical Center.