The most frequently asked questions about the SafetyEdge^SM are shown below and sorted by these categories General | Project Development | Technical | Construction. Select the question of interest to see the FHWA response to the question.

GENERAL QUESTIONS

1. What is the Safety Edge^SM?

   The Safety Edge^SM is a procedure to shape the edge of the pavement at approximately 30 degrees from the pavement cross slope during the paving process. The Safety Edge^SM eliminates tire scrubbing, a phenomenon that contributes to the loss of vehicular control. It has been successfully constructed on both asphalt and concrete pavements.

2. How does the Safety Edge^SM compare with conventional plant mix asphalt paving processes?

    

3. How does the Safety Edge^SM compare with conventional Portland Cement Concrete (PCC) paving processes?

    

4. Why would I change my current practice to include the Safety Edge^SM?

    

5. What type of highways or roads should have the Safety Edge^SM?

    

6. Could the Safety Edge^SM be added to an existing pavement as a project independent of paving/resurfacing?

    

7. Are there any suggested criteria for selecting a demonstration project?

    

8. How should an agency select the best project for an open house to demonstrate the Safety Edge^SM?

    

9. Can we get a loaner Safety Edge^SM device and technical assistance in planning and presenting information?

    

 
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PROJECT DEVELOPMENT QUESTIONS

1. We use thin lift overlays for resurfacing. Do we need the Safety Edge^SM?

    

2. How much will the addition of the Safety Edge^SM cost per mile?

    

3. What is the maximum height and width of the Safety Edge^SM?

    

4. If I use the Safety Edge^SM do I still need shoulder backing?

    

5. Does the Safety Edge^SM have to be placed on gravel?

    

6. Is the Safety Edge^SM beneficial for a project with aggregate shoulders?

    

7. Is there a benefit to installing the Safety Edge^SM on roads with paved shoulders?

    

8. What if a roadway only has limited clear zone available?

    

9. What is the significance of the 30 degree wedge? Why not 20 degrees or so like embankment slopes?

    

10. Will pavement get wider with each resurfacing project that includes the Safety Edge^SM?

     

11. Are there any environmental issues with placing the Safety Edge^SM?

     

12. If a project has rumble strips do we need the Safety Edge^SM?

     

13. What if the slope of the graded material adjacent to the pavement is steeper than the Safety Edge^SM slope?

     

 
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TECHNICAL QUESTIONS (PAVEMENTS/MAINTENANCE/SAFETY)

1. What are the effects of the Safety Edge^SM on the pavement quality and structure?

    

2. Do I need to change my mix design or layer thickness to use the Safety Edge^SM?

    

3. Is the Safety Edge^SM durable? Does the toe break or wedge come apart over a period of time?

    

4. Will corridors with the Safety Edge^SM require more maintenance or less?

    

5. On multiple lift construction, is the Safety Edge^SM constructed on each lift or only the final lift?

    

6. Can I construct the Safety Edge^SM with Warm Mix Asphalt (WMA)?

    

7. Can open graded friction course (OGFC) or rubberized hot mix asphalt-gap graded (RHMA-G) be used with the Safety Edge^SM?

    

8. What type of prep work is needed for the shoulder?

    

9. What subgrade compaction should be specified where the Safety Edge^SM will sit?

    

10. How is the Safety Edge^SM compacted and what is the percent compaction?

     

11. Do I need to install the Safety Edge^SM if my crash data does not indicate we have a pavement edge drop-off problem?

     

12. What type of crash reductions can I expect from the Safety Edge^SM?

     

 
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CONSTRUCTION QUESTIONS

1. What is the cost of the devices that form the Safety Edge^SM?

    

2. How do I obtain the commercially available device?

    

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3. How long does it take to install the Safety Edge^SM device?

    

4. Is there a minimum lift thickness where the Safety Edge^SM, is constructible?

    

5. This looks to be a simple device. Can we make a generic version?

    

6. Can I use my Michigan Shoe (or a similar commercial device) to pave the Safety Edge^SM?

    

7. Does using the Safety Edge^SM change production rate?

    

8. Do I need to modify my paving process to install the Safety Edge^SM on asphalt?

    

9. Does the Safety Edge^SM affect finished ride quality?

    

10. What is the length of an average test strip to determine performance of a Safety Edge^SM device?

     

11. Can a Safety Edge^SM device be placed on both sides to accommodate paving a narrow road in a single pass?

     

12. When paving very narrow widths, how does the Safety Edge^SM device work with a block that narrows the screed width?

     

13. What happens when you come to a driveway when using a Safety Edge^SM?

     

14. How do you pave under the guardrail with the Safety Edge^SM device attached?

     

Page last modified on August 29, 2017