Paramedics have been sent to the Auckland Airport mail centre this morning.
A St John spokeswoman confirmed staff were called to the scene, at Laurence Stevens Drive in Māngere, just after 10am.
Two jeeps and an ambulance crew were at the scene and were "assessing the situation". she said.
A spokesman for Fire and Emergency said they were called to the NZ Post facility near the Auckland International Airport after reports of a chemical spillage.
Members of the fire brigade identified the chemical as safe, but remained at the scene at 11.20am.
