(a) Equipment. Requirements for equipment shall be as follows:

1. (1) Reflex reflective material and fluorescent material that meet the requirements of this chapter shall be affixed to both faces of the warning device. Alternatively, a dual purpose orange fluorescent and red reflective material that meets the requirements of this chapter, referred to in this chapter as dual purpose material, may be affixed to both faces in places of the reflective and fluorescent materials.

2. (2) Each warning device shall be protected from damage and deterioration by one of the following:

   1. (i) By enclosure in an opaque protective reusable container, except that two or three warning devices intended to be sold for use as a set with a single vehicle may be enclosed in a single container.
   2. (ii) By secure attachment to any light-tight, enclosed, and easily accessible compartment of a new motor vehicle with which it is supplied by the vehicle manufacturer.
3. (3) The warning device shall be designed to be erected, and replaced in its container, without the use of tools.

4. (4) The warning device shall be permanently and legibly marked with all of the following:

   1. (i) Name of manufacturer.
   2. (ii) Month and year of manufacture, which may be expressed numerically, as ‘‘6/72.’’
   3. (iii) The symbol ‘‘DOT,’’ or the statement that the warning device complies with all applicable Federal motor vehicle safety standards.

5. (5) Each warning device shall have instructions for its erection and display:

   1. (i) The instructions shall be either indelibly printed on the warning device or attached in such a manner that they cannot be easily removed.
   2. (ii) Instructions for each warning device shall include a recommendation that the driver activate the vehicular hazard warning signal lamps before leaving the vehicle to erect the warning device.
   3. (iii) Instructions shall include the illustration depicted in Figure 3 of Appendix A indicating recommended positioning.

(b) Configuration. Configuration requirements shall be as follows:

1. (1) When the warning device is erected on level ground:

   1. (i) Part of the warning device shall form an equilateral triangle that stands in a plane not more than ten degrees from the vertical, with the lower edge of the base of the triangle horizontal and not less than one inch above the ground.
   2. (ii) None of the required portion of the reflective material and fluorescent material shall be obscured by any other part of the warning device except for any portion of the material over which it is necessary to provide fasteners, pivoting beads, or other means to allow collapsibility or support of the device. In any event, sufficient reflective and fluorescent material shall be used on the triangle to meet the requirements of subsections (d) and (e).
2. (2) Each of the three sides of the triangular portion of the warning device shall not be less than 17 and not more than 22 inches long, and not less than two and not more than three inches wide, Figure 1 of Appendix A.
3. (3) Each face of the triangular portion of the warning device shall have an outer border of red reflex reflective material of uniform width and not less than 0.75 and not more than 1.75 inches wide, and an inner border of orange fluorescent material of uniform width and not less than 1.25 and not more than 1.30 inches wide, Figure 1 of Appendix A. However, this requirement shall not apply if the dual purpose material is used.
4. (4) Each vertex of the triangular portion of the warning device shall have a radius of not less than 0.25 inch and not more than 0.50 inch.
5. (5) All edges shall be rounded or chamfered, as necessary, to reduce the possibility of cutting or harm to the user.
6. (6) The device shall consist entirely of the triangular portion and attachments necessary for its support and enclosure, without additional visible shapes or attachments.

(c) Color. Requirements for color are as follows:

1. (1) The color of the red reflex material on the warning device shall have the following characteristics, both before and after the warning device has been conditioned in accordance with § 163.6(a) (relating to test procedures), when the source of illumination is a lamp with a tungsten filament operating at 2856° Kelvin color temperature. Expressed in terms of the International Commission on Illumination (CIE) 1931 standard colorimetric observer system, CIE chromaticity diagram, Figure 4 of Appendix A, the chromaticity coordinates of the red reflex reflective material shall lie within the region bounded by the spectrum locus and the lines on the diagram defined by the following equations:

   Boundary	Equations
   Yellow	y = 0.33
   White	x + Y = 0.98

2. (2) The color of the orange fluorescent material on the warning device shall have the following characteristics, both before and after the warning device has been conditioned in accordance with § 163.6(a) (relating to test procedures), when the source of illumination is a 150 watt high pressure xenon compact arc lamp. Expressed in terms of the International Commission on Illumination (CIE) 1931 standard colorimetric observer system, the chromaticity coordinates of the orange fluorescent material shall lie within the region bounded by the spectrum locus and the lines on the diagram defined by the following equations:

   Boundary	Equations
   Yellow	Y = 0.49 x 0.17
   White	x + y = 0.93
   Red	y = 0.35

   The 150-watt high pressure xenon compact arc lamp shall illuminate the sample using the unmodified spectrum at an angle of incidence of 45° and an angle of observation of 90°. If dual purpose material is being tested, it shall be illuminated by a 150 watt high pressure xenon compact arc lamp, whose light is diffused by an integrating sphere.

(f) Stability. When the warning device is erected on a horizontal brushed concrete surface both with and against the brush marks and subjected to a horizontal wind of 40 miles per hour in any direction for 3 minutes all of the following apply:

1. (1) No part of it shall slide more than 3 inches from its initial position.
2. (2) Its triangular portion shall not tilt to a position that is more than 10° from the vertical.
3. (3) Its triangular position shall not turn through a horizontal angle of more than 10° in either direction from the initial position.