EMB ERJ 170/175 ER/LR
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Inflight Event / Encounter Weather / Turbulence
General None Reported / Taken
Procedure; Weather
I woke up in the morning and saw the fog; so I took my iPad and reviewed the minimums and the section of [flight manual] for low visibility take off minimums.When we arrived at the airplane I called ATC to ask about the RVR (Runway Visual Range) and they told me the RVR was 2;400 ft. I checked again the plate with the takeoff minimums and we had enough visibility to depart.We started taxi and by the time we get to the runway the RVR had dropped to 1;200 to 1;400 ft. At this point I looked again and I didn't pay enough attention and mixed up Runway 23R and 23L minimums. When we took the runway I checked we had the runway center line lights (Runway 23L has HIRL and CL) so I didn't get alerted and we took off with no issues. After takeoff I decided to look at the plate again and realized that I mixed up the minimums for Runway 23L with Runway 23R. Runway 23L required RVR 1;600 ft.The flight continued normally.I Didn't pay enough attention to the runway on the plate. The other runway is short and was closed. We talked about the minimums with the First Officer and never mentioned the 'wrong runway'.Next time I'll make sure we both review the takeoff minimums plate when a new RVR is announced and make sure both pilots agree on the minimums for the current runway set on the FMS.
E170 First Officer reported misreading the RVR minimums for takeoff; resulting in a departure below RVR minimums.