Fire Rescue Victoria appliances were dispatched to a reported ammonia leak in Epping at 2:15am this morning.
It is believed a caller stated there was a strong smell of ammonia and the site was being evacuated.
There were 28 firefighters who attended the scene, and specialist hazmat and breathing apparatus appliances attended as part of an escalated response.
FRV hazmat technicians dressed in chemical resistant suits using specialist detection equipment located the leak within a building on site.
Hazmat technicians worked with a refrigeration specialist to control the leak.
Police and Ambulance Victoria were also on scene assisting with FRV operations.