Light Bars & Systems
The Federal Highway Administration (FHWA) has granted interim approval for optional use of Rectangular Rapid Flashing Beacons (RRFB) to supplement uncontrolled pedestrian and school crosswalk signs, functioning solely as a warning beacon.
The RRFB is a rectangular shaped, high intensity signal head, which flashes in a wig-wag, rapid flickering pattern. The alternating signals provide direct, ultra-bright concentration as well as wide-angle intensity. The beacons are pedestrian activated: push button or passive detection (several options available).
Studies confirm very high rates of motorist compliance to “yield to pedestrians” (approx. 80%-95%) compared to standard (round) beacons (15%-20% range).
The combination of the following requirements makes RRFB’s extremely effective:
- Signal’s high visibility (light intensity + 2/4−1 strobe pattern).
- RRFB’s installed on both sides of the road facing approaching traffic.
- Supportive signage.
ELTEC‘s Rectangular Rapid Flashing Beacon is FHWA compliant including the updated requirement of Class 1 light intensity. As recently specified by the FHWA, Class 1 RRFB signals (used by emergency vehicles: police, fire and ambulances) must be rated to 200 cd (candela or ‘candle power’). Surface area of the signals does not determine the level of brightness. The type of LED and reflector used within the signal head determines how many must be used to provide the required Class 1 light level. ELTEC has always used lab Certified Class 1 LED’s.
The FHWA requires signals on both sides of the road for approaching traffic. Because of diverse traffic patterns, ELTEC has designed two styles of RRFB light bars. Both light bars have recessed signals to minimize vandalism and offer an optional pedestrian verification signal housed on the end of each light bar.
One-sided with 2 RRFB’s: Used on divided highways with a median or one-way streets. This light bar mounts to tapered, wooden, standard 4 1/2” O.D, or other diameter pole sizes where banding is appropriate. Optional: One or two end-mounted signals for pedestrian verification.
Two-sided wraparound with 4 RRFB’s: Used with two-way streets/highways, or for median use in conjunction with the one-sided light bar. It mounts to a 2 3/8” or 4 1/2” O.D. pole, or 2 1/2” Telespar. Optional: One or two end-mounted signals for pedestrian verification.
The FHWA does not specify any light bar finish. ELTEC has two ‘off-the-shelf’ options: Federal Yellow or brushed aluminum. Optional powder coated custom colors are also available (community or school colors, for example).
Both light bars can be retrofitted to existing (poles) pedestrian crossings that have no signals or are currently using round flashing beacons. The light bars work with either DC (solar) or AC systems that incorporate a 120VAC to 12VDC power supply. ELTEC also manufactures complete solar powered or AC systems.
Some municipalities and state DOT’s require night dimming. ELTEC’s custom RRFB flasher offers optional 6-stage night dimming without altering the 2/4-1 strobe pattern.
All ELTEC solar powered (DC) systems are sized for optimal performance to ensure the light intensity never fades or fails. Should a crossing have less than 350 activations a day or more than 1,200 we guarantee our DC systems will not be undersized for the number of average daily activations. With all solar powered systems, we will give you a sizing report confirming the reliability of system performance.
Units/poles are typically connected by radio for wireless operation, eliminating the need to trench or bore. The radios have 65,000 different addresses to ensure that only the desired units operate from a signal. Units may be hardwired if desired.
FHWA UPDATES: OFFICIAL INTERPRETATIONS
On September 27, 2012, the FHWA determined that daytime dimming of RRFB indications is not allowed (applies to solar powered systems). All existing DC systems with ‘automatic dimming/power management’, etc., are no longer in compliance. Dimming at night is acceptable due to the “excessive glare during nighttime conditions”. FHWA Daytime Dimming Interpretation Letter
On June 13, 2012, the former 2/3 flash pattern was updated to reflect the actual flash pattern initially tested. FHWA Flash Pattern Interpretation Letter
On August 8, 2012, systems installed or shipped prior to July 6, 2012 with the former flash pattern are ‘grandfathered’ and not required to be modified/updated to the new flash pattern. FHWA Former Flash Pattern Interpretation Letter
On January 9, 2012 the FHWA clarified the SAEJ595 light intensity standard. Only “Class 1 yellow lights are to be used for RRFB’s…” FHWA Light Intensity Interpretation Letter
RRFB LIGHT BAR SPECIFICATIONS
Dimensions (one side/2 RRFB’s)………………………3.5” H x 20” W x 2.625” D
Dimensions (wrap-around)………………………………..3.25” H x 20” W x 8” D
Power required……………………………………………………………….12 VDC
SAE J595 Class 1 Certified LED’s……………………AMECA Accredit Laboratory
Flash rate …………………………………………………..75 flash cycles/minute
Optional: 6 stage night dimming…………………reduces light intensity by 70%
All components are designed, manufactured and assembled in the U.S.A.