Cape Medical Response, Cape Town fire and rescue services, police and the NSRI responded to the emergency.
"CPR efforts were continued by paramedics and following extensive CPR efforts a pulse was restored and the man has been transported to hospital ... by ambulance in a critical condition," said Zimmerman.
The diver who pulled him from the water was taken to hospital in a serious but stable condition.
Police divers recovered the dumped diver gear about 50 metres offshore.