Enhancements coming to the Star Rating for Schools model – all the information you need to know

According to Safe System principles, vehicle speeds should not exceed 30km/h where vehicles and pedestrians mix. This is the tolerable speed in the event that a conflict between vehicle and pedestrians occurs, giving time for the vehicle to stop or to significantly reduce its speed and the energy associated with the impact. SR4S helps measure, monitor and communicate the risk children are exposed to on a school journey. We know that the behaviour and physiologically of children makes them highly vulnerable on the roads.

For the SR4S model review, these Safe System principles were considered as follows:

• A road without crossings or sidewalks should not achieve 5 Stars where vehicle speeds exceed 30km/h.
• It should not be possible to achieve 5-Stars while having to cross multiple traffic lanes in each direction without a crossing facility.
• 3-Star roads without pedestrian facilities should not be 40km/h or above.

The star ratings will be calculated on largely the same road attributes as before; however, several sets of risk factors that underpin the Star Ratings have been updated. This means that the total scores for the risk in each location will change, which may result in a different star rating result. Now different combinations of road elements may be required for a 4 or 5-star location, for instance. In general, the new results will be more rigorous, and in order to achieve 3 star or better for your locations you may need the combination of more safety elements and lower speeds compared to the previous version of the model.

The main enhancements that are being made to the SR4S model are:

1. Speeds: the underlying risk factors have been adjusted and speeds may now be recorded in 5km/h (or 5 mph) increments starting from 0km/h (or 0mph).
2. Traffic flows: introduced new risk factors for traffic flow increments of 1,000 vehicles per lane up to 20,000 vehicles per lane.
3. Sidewalks: new risk factors have been introduced which reflect the new speed and traffic flow risk factors.
4. Number of lanes: risk factors have been introduced for Pedestrian Along crashes, increasing risk as the number of lanes does.
5. risk increases as the number of lanes does.
6. Paved shoulders: risk factors have been revised as part of the new sidewalk risk factors. Risk factors for paved shoulders previously only came into effect in the absence of a sidewalk. A notable change is that the risk factors for paved shoulder 0-1m wide are now equal to that of no facility.
7. Lane width: lane width risk factors for the along crash types relate to vehicle run-off have been adjusted for rural roads, where they apply only to shoulder facilities (paved shoulders 1-2.4m and >2.4m). Urban risk factors have been removed as evidence of risk for pedestrians and bicyclists did not support the current risk factors.
8. Property access points: property access is now considered in the Along crash type, which better represents the risk of vehicles moving in and out of driveways to pedestrians, irrespective of whether there is an intersection present.  
9. Pedestrian crossing facility: new risk factors have been introduced which reflect the new speed and traffic flow risk factors, including when operating speed surpasses acceptable thresholds; new category for unmarked crossings introduced.
10. Pedestrian crossing quality: new combined risk factors for poor quality grade-separated crossings (e.g. bridges).
11. Intersection type: risk factors amended to better account for crossing distance.
12. Number of lanes, lane width and paved shoulder width: new risk factors that account for the combined effect of number of lanes, lane width and paved shoulder width for the overall crossing distance for pedestrians.
13. Median type: pedestrian crossing risk factors related to median type have been removed (except for one-way roads). Where a median functions as a refuge, this is now recorded as the pedestrian crossing type with a refuge (i.e. change to coding rules).
14. Vehicle AADT: conditional AADT per lane pedestrian factors have been updated so they now apply for roads with no facilities, unmarked crossings and crossings with refuges only.
15. Intersecting road volume: new risk factors introduced to allow high traffic flows on side roads to be recorded.
16. Pedestrian channelization: update of pedestrian fencing impact on pedestrian crossing flows and its combination with grade separated crossings.
17. Decimal stars: new type of presentation indicating the scale of star rating within the same band.
18. Star Rating bands: adjustment of the star rating thresholds to accommodate new risk factors and the Safe System principles.

Currently, a simple star rating is calculated for each location assessed with SR4S. With the decimal star ratings, it is possible to see where in the band the rating is. For example, a star rating of 3.5 stars indicates that it is in the middle of the 3-star band, while a star rating of 3.9 stars indicates that it is at the top of the star rating band.

If you would like to learn more about the updates made to the model, access our methodology page and the detailed report – irap.org/research-and-technical-papers/

Any existing assessment results produced using the previous model will not be automatically changed in the system. You will have the option to keep your results as they are or update them to the latest model version once it is available. We will be happy to further discuss your special needs on managing your data and performance tracking.

The model update will result in relatively few changes to the way of coding some road attributes, for example:

• Sidewalks – pedestrian facility separation from the road measurement. The distance of sidewalks should now be recorded from the edge of the roadbed or the curb, not the edge of the driven lane. Paved shoulders are now factored in as providing added buffer if present.
• Sidewalks – poor and moderate quality sidewalks. New coding guidance is being provided for poor quality and moderate quality sidewalks.
• Pedestrian crossing facility: refuges on roads with medians. Where there is a road with a median that also functions as a pedestrian refuge, this is now recorded as the pedestrian crossing type with a refuge.

Please make sure to compare pre- and post-intervention assessment using the same model version. We will provide you a disclaimer explaining the model review and any implications in the results. If you conducted your pre-intervention assessments with an older version of the model, it may happen that your post-intervention assessments may generate star ratings lower than your first assessments. In this case, we would advise you to update your pre-intervention assessments to the new model. This will make your assessments before and after comparable. We will also provide a disclaimer that can be used in your reports and presentations informing the version of the model with which your assessments were performed. Feel free to get in contact if you need any assistance to manage your data.

You can keep your previous assessments saved in the SR4S and no updates to the new model are required. If you plan to publish your results, however, you will be required to update your assessments to the latest version of the model.

No. After the model update is deployed, you will be required to use it for any new assessments created in the SR4S platform.

Based on the latest research and principles of Safe System, bold measures should be taken in terms of road design and speed management to ensure pedestrian safety. Humans, especially children, make mistakes when using the road. For this reason, risk factors have been updated to reflect the real behaviour of all road users, and these lead to a rigorous assessment of risk. This new model was tested in multiple SR4S locations to ensure consistency with these principles and to meet feedback from partners using the tool in more than 60 countries.

No. The previous and the updated models represent a proactive approach to road safety that can be used to measure, monitor and communicate the risk for pedestrians. It is natural that as experience is developed and new research and evidence reviewed, updates to the model will incur. In some specific situations in the past, partners experienced star ratings that were not necessarily consistent with what they perceived, based in evidence and experience, to be the actual level of safety. This feedback, combined with a review of the latest research and evidence, has been valuable in improving the models.

The Global Technical Committee oversees our models and advises about any needs for updates on a regular basis. This update to the model represents an important and improvement and at this point there is no plan to conduct a further report in the short to medium term.

After the model update is implemented, you will be notified by email. If you have any ongoing project and needs support with managing your old and new results, please get in contact with schools@irap.org and we will be happy to support you. If you need to compare your old data and new assessments, please let us know and we will help you update your previous assessments and manage your results. In 2023, we are launching an updated SR4S video course, we would suggest you take a look as a refresher before using the new model.