Frequently Asked Questions Related to Interim Approval 21 – Rectangular Rapid-Flashing Beacons at Crosswalks

The following list of questions relates to Interim Approval 21 – Rectangular Rapid-Flashing Beacons at Crosswalks:

1. Why was Interim Approval No. 11 (IA-11) allowing provisional use of the RRFB terminated and why is FHWA allowing it again?
2. Why are proprietary traffic control devices not allowed?
3. What is the status of the crosswalk treatments in the FHWA's informational brief?
4. Is the RRFB superior to the other crosswalk treatments that are available?
5. Is the previous Interim Approval, IA-11, once again valid?
6. Must an agency request a new approval under IA-21 to continue installing RRFBs if it previously obtained the FHWA's approval under IA-11?
7. What happens to the RRFBs that are already installed by the approved agencies?
8. How do agencies determine whether an existing device is "serviceable" or has reached the end of its service life?
9. Does this action apply only to projects that involve Federal funds?
10. Could a variation of the RRFB, changing either shape and/or flash rate, be allowed?
11. What if agencies continue to install RRFBs under IA-11, but do not apply for approval under IA-21?

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Questions and Answers

1. Why was Interim Approval No. 11 (IA-11) allowing provisional use of the RRFB terminated and why is FHWA allowing it again?

   Answer:

   • IA-11 was terminated due to patent protection issues associated with the RRFB. The MUTCD does not allow patented traffic control devices. Because the patents have been abandoned, the RRFB is now again eligible for consideration as a traffic control device. The termination had nothing to do with the effectiveness of the RRFB, which is why the FHWA is once again allowing its use under provisional terms.

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Why are proprietary traffic control devices not allowed?

Answer:

• Patented traffic control devices run counter to the principle of uniformity. If one patented device for a specific application were to be allowed, then competing patented devices developed to serve the same purpose with unique designs could not be denied approval. The result would be a violation of the road user's expectancy due to the inconsistent appearance and messages of these widely differing devices. Traffic control devices are designed for instant recognition and response by the road user. Without this consistency, there would be longer response and reaction times, potentially compromising the safety of road users.
• The allowance of proprietary traffic control devices in the MUTCD also violates the general prohibition against the Federal government endorsing or appearing to endorse a product, company, or individual.

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2. What is the status of the crosswalk treatments in the FHWA's informational brief?

   Answer:

   • The treatments described all comply with the MUTCD and no special approval is required from FHWA to use those treatments.
   • The RRFB is one additional treatment that is now available to any agency that requests and obtains the FHWA's approval to use it under the terms and conditions of IA-21.

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3. Is the RRFB superior to the other crosswalk treatments that are available?

   Answer:

   • In some cases, the RRFB might be superior to the other treatments. As is typical for traffic control devices, the effectiveness of a device can depend on the conditions under which it is installed. For example, the RRFB, which exhibited high rates of yielding in many cases, also exhibited low rates of yielding under some conditions. In simpler terms, finding the most effective device or combination of treatments for the specific conditions at the location is the key.
   • The FHWA is currently conducting additional research into the comparative effectiveness of various treatments. We hope that this research will provide better assistance to practitioners in selecting the most appropriate treatment(s) for the specific conditions of each location.

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4. Is the previous Interim Approval, IA-11, once again valid?

   Answer:

   • The previous Interim Approval, IA-11, remains terminated. Its provisions and approvals are superseded by the new Interim Approval, IA-21.

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5. Must an agency request a new approval under IA-21 to continue installing RRFBs if it previously obtained the FHWA's approval under IA-11?

   Answer:

   • Yes. The previous Interim Approval, IA-11, remains terminated. The new Interim Approval, IA-21, contains revised provisions that incorporate previous relevant official interpretations and that reflect more recent research and experience with the device that agencies must agree to and comply with if they wish to install RRFBs.

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6. What happens to the RRFBs that are already installed by the approved agencies?

   Answer:

   • Existing RRFBs that were installed under the terms and conditions of IA-11 may remain in operation until they reach the end of their useful service life. Existing RRFBs should be reprogrammed to the new flash pattern specified in IA-21 as part of a systematic upgrading process, such as when maintenance is performed or when signs are replaced.

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7. How do agencies determine whether an existing device is "serviceable" or has reached the end of its service life?

   Answer:

   • The MUTCD does not specifically define "serviceable" condition because serviceability will depend on the type of device under consideration. In general terms, if the device is capable of being serviced with minimal effort or replacement parts so that it continues to operate as intended, and the device is otherwise substantially intact, then it can be considered to be in serviceable condition. If the device is damaged or not operational beyond reasonable repair, then it is likely no longer serviceable.

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8. Does this action apply only to projects that involve Federal funds?

   Answer:

   • No. The MUTCD applies to all roads open to public travel regardless of funding source (see Paragraph 2 of the MUTCD Introduction). Interim approvals are administered under the provisions of the MUTCD. Therefore, the action applies to all roads open to public travel regardless of funding source.

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9. Could a variation of the RRFB, changing either shape and/or flash rate, be allowed?

   Answer:

   • All flashing beacons are required to comply with the provisions of the MUTCD (see Chapter 4L), and all RRFBs must comply with the terms and conditions of IA-21.

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10. What if agencies continue to install RRFBs under IA-11, but do not apply for approval under IA-21?

    Answer:

    • Traffic control devices on roads open to public travel must comply with the MUTCD. As with any non-compliance, the FHWA Division office will work with the State agency to achieve compliance.

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