Safety in Numbers needs an exhaustive feature library to allow for useful mapping of roadside features. To create this library we have tried to combine all of the public informaiton that exists regarding road safety devices.
Below is a summary of the data sources and process we used to arrive at our list of features.
The current working list, which sets the menus on map.safe7y.com, can be found in our gitlab repository. If you have suggestions for changes to the list please submit a Gitlab Issue to the relevant project.
In 2013 the FHWA published an excellent guide to road safety hardware. It was updated and expanded in 2018. It is not currently hosted publically on any of the FHWA's or USDOT's web services, but Safety in Numbers was provided with a PDF copy which is hosted here for posterity.
This provides key information for VehicleBarrier and Terminal features and, where possible, we have selected these device names as the defining names for the Safe7y device list.
Task Force 13 provides a web-based hardware guide which is an invaluable resource for VehicleBarrier and Terminal features. It is regularly updated and a recent version has been incorporated into our feature list.
You can find the guide at tf13.org/Guides/
The MUTCD is the definitive sign guide for the United States. While not all of the States use it, it guides sign shape, color and wording across the country. The guide is prepared by the National Committee on Uniform Traffic Control Devices (NCUTCD) and published by the FHWA and AASHTO.
You can find more detail on their site https://mutcd.fhwa.dot.gov/.
We take our list of signs from the html version of the manual.
As you might guess, this resource informs Sign features but the MUTCD also guides RoadSurfaceMarking features.
Minnesota released an excellent roadside hardware guide back in 2019. This is not hosted publically, but we have a copy of it here on the wiki. It covers Vehicle Barrier and Terminals.
roadside_hardware_handbook.pdf
Our goal is a clear list of features that can be recognized from the data our analysts have, typically street view images and satellite footage.
The first step is to take each of the data sources and express their features in a functional format. These are provided here to allow the public to audit our work and, maybe, to save some human effort down the line.
2018-usdot-resource_sheet-converted.xlsx
210211-tf_13_devices-converted.xlsx
2009-mutcd_signs-converted.xlsx
Next we combined all the features into a master list, preserving the source information and a few important reference fields from the source lists.
210213-safe7y_feature_master_list.xlsx
Using this master list the Safety in Numbers staff removes the duplicates, groups similar devices under a single Device name and double checks the Feature and SubType assigned to each device. A single Device in the Safety in Numbers data set may correspond to several similar devices in the original source material (e.g. the QuadGuard Elite M10 MASH EndTerminal corresponds to a family of similar devices described in the TF 13 guide).
The current working list, which sets the menus on map.safe7y.com, can be found in our gitlab repository. If you have suggestions for changes to the list please submit a Gitlab Issue to the relevant project.