SAE J595_202108

This document provides design guidelines, test procedure references, and performance requirements for directional, single color, flashing optical warning devices used on authorized emergency, maintenance, and service vehicles. It is intended to apply to, but is not limited to, surface land vehicles. The color green was added to the photometric and color requirements for Class 3 devices to reflect the use of green warning lamps to identify an incident command post, the private vehicles of volunteer firefighters or EMS personnel, or private security vehicles as described in U.S. Fire Administration document FA-336/February 2014 “Emergency Vehicle Safety Initiative.” Due to societal associations of the color green with the concept of normalcy (green GO signal of traffic lights, green indicator lamps to signify a device is operating within its normal operating limits, etc.), the color green shall not be used on its own for applications that require Class 1 or 2 performance levels. Electromagnetic interference guidelines were added for devices containing electronic controlling elements, converters, regulators, or actuators. Emergency, maintenance, and service vehicles utilize two-way radio communication devices that can be adversely affected by excessive electromagnetic emissions from warning devices. 2.1.1: Document SAE J1889 is no longer an applicable document since the definition of photometric stability was added to this document. SAE J2357 was added because it is now referenced in the electromagnetic interference guidelines. Section 3: Reordered and renumbered definitions to place them in alphabetic order per ANSI guidelines. 3.1: The phrase “to call for the right-of-way” was added to the definitions to clarify conditions that indicate the need for Class 1 performance and to provide common language with SAE J2498. 3.5: The definition of the term “duty-cycle” was added to clarify its meaning within the document. 3.6: The limitation of “in all modes if the mode of the device is vehicle operator adjustable” was removed from the determination of when multiple EWD lamp assemblies can be considered as a single device because it is unneeded. 3.7: The definition of the term “emergency warning device photometric stability” was added to clarify its meaning within the document. 3.9: The definition of the term “flash energy” was added to clarify its meaning within the document. 3.11: The definition of the term “on-time” was added to clarify its meaning within the document. 3.14: The definition of the term “peak intensity” was added to clarify its meaning within the document. 3.17: The definition of the term “pulse width modulation” was added to clarify its meaning within the document. 3.19: The definition of the term “Talbot’s law” was added to clarify its meaning within the document. 3.20: The definition of the term “warning mode” was added to clarify its meaning within the document. Section 4: Modified the language in the Class definition to include single warning mode allowance. Added the appending of the letter “M” to the device marking code to indicate devices that contain warning modes of different performance. Section 5: Renumbered the section to improve clarity. 5.1.1: Added random vibration allowance. 5.1.5: This section was re-written to clarify the measurement procedure and match the practices of test laboratories. Methods are provided to determine the photometric performance of un-tested flash patterns by photometric testing of a single flash pattern and determining an adjustment factor that can be applied to the photometric test results of the tested flash pattern. References to SAE J1330 and SAE J1889 removed. 5.2: Revised the text to clarify incandescent sources may be operated steady burning and that device chromaticity be tested at 1 minute and when photometric stability has been reached. 5.4: Revised the flash characteristics that must be measured to the ones needed to determine compliance to the definition of a flash. 6.4: References to the definitions of a light pulse and flash were added to the requirements to eliminate ambiguity. The list of required characteristics that must be included in a report was deleted.