Date: 201305
Local time of day: 0001-0600
Location: SLC.Airport, UT
Light: Daylight
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground SLC
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
Detector: Person Air Traffic Control
When detected: Taxi
Result: Air Traffic Control Issued Advisory / Alert; Air Traffic Control Provided Assistance; Flight Crew Became Reoriented
Contributing factors: Airport; Chart Or Publication
Primary problem: Chart Or Publication

Narrative: Taxi out from Gate and told by ramp to taxi to 'Spot 7.' Lots of traffic and all departures are assigned a 'spot' to taxi over to and then you must wait until called upon by Ground Control for further instructions. So there are square spots and round spots depicted on the 10-9 and 10-9D. Our 'Spot 7' is supposed to be a round one. Now the weather is not a factor; but there is a bunch of lines running in all directions; some green; and black; yellow; yellow bordered by black; red boxes; and even big; big green outlined boxes. Of course none of these lines are depicted on any chart we have; both paper and the public version I have on my iPad. So we taxi out to the first round 'Spot 7' which seems about right because we can also see the blue square with a white 6 in front of us about 40 yards away. Then we began our wait. Well; about 7 minutes later; the Ground Controller; who has been calling all the other aircraft by their spot number; calls us 'Air Carrier XXX; taxi 'Spot 7' for 34L.' F/O reads back the clearance and we get no correction so good to go right? Well; clever me thought I had figured out this maze of lines that had these ball numbers on them and once assigned the 'spot' number; you just follow that line out to either Taxiway Alpha or Bravo to Runway 34L. First Officer is now confused because prior to making the left turn onto Taxiway Echo to follow line 7 from 'Spot' 7; we pass a triangle with a 7S within it and there are no triangles depicted on our 10-9's. Crap. Next call is now a familiar tone I get at home when in some kind of [trouble]. 'Air Carrier XXX where are you going!!!?' I responded back;' taxiing to Runway 34L via Spot 7 as assigned.' 'Air Carrier XXX; I told you to taxi to Spot 7 and expect 34L!' screams the Ground Controller. 'Well ma'am we were at 'Spot 7' and read back to you what we are doing now; taxiing to Runway 34L. You did not correct the read back so what do you want us to do now' I retorted. 'Air Carrier XXX; turn right at Foxtrot 2 and follow the CRJ on your right to RWY 34L.' First Officer answered and we proceeded as told. Once airborne on the TWF RNAV 1 Dept; we are faced with more confusing clearances during the climb which I have addressed with Airspace/Technology for further clarification. After leveloff at FL380; the First Officer and I began digging through every document we have on ZZZ. There is nothing to describe the ball numbers or colored lines. One odd note I find is a mention of SMGS and Low visibility Taxi Procedures as a stand alone statement top left side of 10-9A. What conclusion does one draw from that statement? Furthermore; the iPad Chart version of the 10-9C/D is very difficult to discern unlike the paper version. This is another example of what should be absolutely standardized airport markings and procedures in the US. Only SFO and CYVR have clear and concise markings depicted exactly as you see them on the ramp published on their 10-9; 10-9As; 10-9B or low visibility charts. Even the colors are explained in the legend and on the 10-9B for SFO. I could not even imagine what one would do if the first time you landed in SLC during CAT III operations and no clue what the all markings meant. It is time to clean up the non standard procedures at these airports if the FAA's number one goal is to prevent incursions.




Synopsis: The crew of a Boeing 737-800 was given confusing taxi instructions by Ground Control referencing non-standard markings and procedures that could not be deciphered with the onboard resources available to them on the flight deck.