Date: 201912
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: Mixed
Weather elements / visibility: 10
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Flight Deck / Cabin / Aircraft Event Illness / Injury
Detector: Person Flight Crew
When detected: Aircraft In Service At Gate; Pre-flight
Result: General Maintenance Action; General Flight Cancelled / Delayed
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: This is a General Safety Concern submission. Five minutes prior to push; the First Officer and I were seated; we had completed all briefings and the Before Start Originator Checklist. We discussed ZZZ information page stating deice was completed at the south ramp; NOT at the gate. The ground crew had queried and replied via knocks to aircraft skin and hand signals to our having started the APU and their intent to remove electric/conditioned air. We replied and they removed both. Passenger boarding was complete. Approximately 140 Passengers were onboard. As the First Officer brought both Pack Switches to Auto; the flight deck filled with grayish smoke. The First Officer immediately placed both Pack switches and APU bleed switch to OFF. We also opened both flight deck windows to clear. The First Officer announced Iceman's presence at the aircraft left of our aircraft. As the smoke dissipated I ensured the First Officer was comfortable with matters at hand while I went to have a conversation with Iceman. I then immediately left flight deck for the ramp in attempt to flag down the Iceman truck.As I exited; I noted the cabin did not appear to have been affected nor were passengers appearing to ready themselves to evacuate up the jetway. As I approached and signaled a retreating Iceman; the Driver exited the truck. I asked if he had applied any fluid near the APU. He said they were told by Flight Operations to deice our tail. And so he did. I explained the APU ingested some fluid and thereby the Packs fogged out the flight deck. I also emphasized we have 140 Passengers onboard; and he did not coordinate or communicate with us before performing his tail deice. I also said that the ZZZ information page stated that deice operations does NOT happen at the gate. I also explained the risk that had that fogging de-icing fluid entered the cabin there may have been a 140 Passengers auto-evacuation placing them in danger. He apologized and said he did not realize we were on APU power. Nor did he seem to understand that even if you avoid spraying the APU the dripping or excess can flow into the intake and cause incredible amounts of fogging. I re-emphasized that is why there must be communication and coordination with the flight crew and that is why we have checklists and procedures for this. And that it even starts with our configuring the aircraft.I then returned to the jetway and pulled aside the Ops Agent and I believe a Supervisor. I explained what we believed happened and the risks we just exposed ourselves and the passengers to with that lack of coordination. I also stated Iceman said Flight Operations directed home to deice the tail at the gate. They understood and apologized for the error. The First Officer and I delayed for at least 10-15 minutes before reapplying APU Pack air. We then discussed any possible risks we may have overlooked. All components; conditions and indications appeared normal so we safely moved forward to getting pushed; deicing remainder of aircraft; and departed uneventfully. I realize not every Company employee can know all other employee jobs completely. I do believe this Iceman incident was caused by on over emphasis to be on time. Unfortunately; Iceman did not notice we were on APU power (even though the normal SOE would have it as such) nor did he see conditioned air was disconnected. The real risk was in performing a deice action with Passengers fully boarded at the gate at that time despite the ZZZ information page specifying deice would NOT be performed at the gate. Had the First Officer not been so proactive in reacting to the fogging; several passengers may have fearfully auto-evacuated into harms way.




Synopsis: B737-700 Captain reported a communication breakdown with ground crew resulting in a smoke event due to De-Ice crew procedural error.