The accident happened at the Venetian Catering Hall in Garfield on Friday night.
Police say the DJ brought a carbon dioxide canister to use for special effects. The canister burst without warning and injured two men and a woman who were on the dance floor.
The victims, ages 32-34, were taken to Hackensack University Medical Center. Their injuries are not life-threatening. All were reported in stable condition.
The wedding was halted. The Venetian did not sustain significant damage.
An investigation into the explosion continues.