Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Time Pressure; Distraction; Communication Breakdown
Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors
Event occurred during preflight/ground operations in ZZZ after checking the ADG (Accessible Dangerous Goods) container and receiving the Captains signature on the aircraft DG manifest. As I returned a signed copy of the aircraft DG manifest to the Ramp Agent I also handed them the red/white striped DG paper-work folder. Neither myself or the Ramp Agent recognized this and we departed ZZZ for ZZZ1 without the folder on board aircraft. I still retained a signed copy of the aircraft DG manifest in my pocket; but did not have the red/white folder. The event was recognized in ZZZ1 when the Ramp Agent could not find the red/white folder. It was an oversight and mistake on my part.Overall; It was a momentary brain lapse that caused this. One Contributing factor was rapidly changing weather conditions (snow/visibility) captured my attention/thoughts. While starting/thinking ahead is important; this could have been prevented by simply slowing down and handling one task at a time.
As a B757 crew we potentially performed a take-off below take-off minimums on Runway XXR at ZZZ. At show time the weather was 10SM vis/CLR skies. However; about 10 minutes prior to pushback a snow storm moved into the area and the weather began rapidly changing. We decided to de-ice/anti-ice. This; along with getting stuck behind addition de-icing aircraft on the ramp; led to delays leaving ZZZ. As we finally taxied we continued to monitor for new ATIS information. As we waited to depart behind an aircraft in front of us; the visibility dropped to 1/2 SM. It was originally my take-off as the FO (First Officer); however my Captain made the decision to perform the takeoff himself due to the snowy conditions and changing visibility. While waiting on the taxiway; behind an aircraft in front of us; my Captain checked the page for takeoff minimums on Runway XXR at ZZZ. He saw that 1/2 SM was the Standard Takeoff mins for that runway. However; after reviewing it later it was determined that he misread the chart as 1/2 SM was the STD mins for 3 or more engine aircraft and 1 SM for 2 engine aircraft (we were operating a B757). I did not look up the page for myself and therefore did not do a good job at backing up the Captain on the decision to depart. However; we departed ZZZ on XXR without incident. Later; After discussing what occurred; we recognized that taking off with 'Adequate Visual Reference' required 1/4 SM vis. We could both definitely agree that we had more than adequate visual references to take-off as the HIRL and runway marking were easily visible throughout the takeoff procedure. However; neither of us was 100% sure that those mins (1/4 SM) applied to us in that situation. We are continuing to do research and reach out to knowledgeable resources.
Air Carrier flight crew reported gate departure without required Hazmat document folder. Flight crew did have a signed copy of the DG manifest but not the required company folder.