A St John spokeswoman said the person was in a moderate condition. An ambulance attended the scene at the new Spark building about 7.51pm on Wednesday.
"We treated one patient and transported them to Christchurch Hospital," she said.
A police spokeswoman said they had referred the incident to WorkSafe.
A WorkSafe spokesperson said it is investigating the incident.
"WorkSafe was notified of an incident at the Christchurch Spark building last night.
"We understand a person may have inhaled chemicals. We are making initial inquiries to establish what our next steps might be.
Two fire crews from the Christchurch central station also attended the scene.