Coding Questions

I am using the standard excel form for input of data. Would appreciate if anyone could advise on the following questions?

  1. Observed flows for motorcycles, pedestrians (across and along), vehicles

Are these (i) flows in terms of number per hour or (ii) just the number observed in the video along the 100m of travel? If it is just random numbers as observed, then is there a recommended way to convert, as I am using iRAP on design drawings first?

  1. Roadside severity - drivers side distance

Can you confirm that this is measured from the left edge of the traffic lane and may include the width of an opposing traffic lane?

  1. Intersections and property access points

Would the majority of minor tracks or minor streets criss-crossing a main road considerd an intersection or property access point?

  1. Number of lanes

For divided roads where iRAP is conducted for each direction, does the number of lanes refer to the entire road or just a particular direction?

  1. Using iRAP’s definition as follows, all bends less than 200m will be considered very sharp bends even though approach speed is low in some circumstances. Do I need to strictly adhere to these values or select according to say speed differences (approach and within bend)

  2. Vehicle Parking

Does this include any parking including designated parking space?

Hi there,

  1. During the coding just count the number of pedestrians, bicyclists and motorcyclists that you see each 100m. These numbers are not directly used in the analysis, they can be used to help inform estimates of the peak hour flows (columns BL to BP of an upload file). If you are coding designs and do not have baseline coding, you can leave the observed numbers blank. In the abscene of survey counts, we can use the observed flows (if there is some), land use, intersection, sidewalk, crossing attributes to make estimates of peak hour pedestrian and bicycle flows. It’s important to note that Star Ratings are produced if flow > 0, the Stars don’t change if flows increase, but the fatality estimations are dependent on relative flows. ie other things being equal more flow = more fatalities.

  2. For an undivided road, the distance to a roadside object is measured from the edgelines, on both sides. For a divided carriageway, the distance to a driver side object is measured from the driver side edgeline. The first object encountered might be in the median or across the other side of the opposing carriageway. The Coding Manual has some good illustrations on this: http://downloads.irap.org/docs/RAP-SR-2-2_Star_Rating_coding_manual.pdf

  3. Generally if the side road is a public road and ‘official’ it should be coded as an intersection. You can use the intersecting road volume attribute to record how busy the intersection is.

  4. Record the number of lanes in the direction of travel. Eg a divided road might have two lanes in each direction. So the number of lanes coded is two.

  5. Adhere to the advice in the coding manual. Remember that operating speed is recorded separately.

  6. If the parking is within 2m of the outside edge of the drivable lane it should be recorded.

Hope this is helpful!

Greg

Sir, The bicyclists or motorcyclists we coded in a first 100 m section , then again the same motorcyclists come in next 100 m section,then what should we do ? we considered it in next section also ?

Hi there,

Just count the number you see in each 100m segment. It doesn’t matter if it’s the same motorcycle that you saw in a previous 100m segment.

Greg

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