Category Archives: Types of Reflective Tape

Different types and classes of retro reflective tape

What is DOT C2 Reflective Tape ? – Specifications Certification Definition

 

The term “DOT C2” reflective tape is used quite often in regards to marking tractor trailer rigs 80 inches wide or wider and over 10,000 lbs GVWR.  However, what the term “DOT C2” means is seldom discussed. Most people know that the letters DOT mean “Department of Transportation.  Also, some people know that the term C2, C3 or C4 refers to the width of the tape. (2″,3″ or 4”)  Most people do not know what it takes for a reflective tape to be certified as “DOT C2, C3, or C4”.  This article is meant to help you understand what these requirements are so that you can be sure that you are using the correct product on your vehicle.  In the event of an accident, having the proper markings is especially important.  We recommend Reflexite DOT tapes.  They invented prismatic reflective tape and their products are respected and recognized around the world.  The downsides to using a cheap substitute are simply not worth it.

In order to be certified as DOT C2, C3 or C4 tape, certain requirements have to be met. These requirements involve the construction of the tape, the color, the width, the spacing of the alternating colors, the performance,  and the reflectivity. If a tape has been certified to meet these standards then the manufacturer is allowed to put DOT C2 certification on it. The specifics of the requirements are as follows.


Construction – The requirements for the basic construction of the film are very straight forward.  This is how virtually all reflective tapes are constructed.  The regulation is as follows:

S5.7.1.1  Construction. Retroreflective sheeting shall consist of a smooth, flat, transparent exterior film with retroreflective elements embedded or suspended beneath the film so as to form a non-exposed retroreflective optical system.


Color – DOT tape must be made with white and red alternating colors.  The white color on prismatic tapes often looks silver but reflects white at night. The exact wording of the regulation is as follows:

(a) Retro-reflective sheeting shall be applied in a pattern of alternating white and red color segments to the sides and rear of each trailer, and to the rear of each truck tractor, and in white to the upper rear corners of each trailer and truck tractor, in the locations specified in S5.7.1.4, and Figures 30–1 through 30–4, or Figure 31, as appropriate.  (see this article for placement details)


Spacing -The red and white (silver) segments are required to be a minimum of 12 inches plus or minus 6 inches.   That would be between 6″ and 18″  There is an exception where the tape must be trimmed to avoid obstructions when installed.  Also, neither the red or white colors can exceed two thirds (2/3) of the total.

There are two types of DOT tape available.  A 7″ white / 11″ red and a 6″ white / 6″ red.  If you run the numbers you will see that both meet the spacing requirement.  On 7/11 tape the 7″ white would represent 39% of the aggregate and the 11″ red would represent 61%.  The 6/6 would be 50% each.  To the best of my knowledge all 50 states allow you to use either the 7/11 or 6/6 type DOT tape.  The regulation is quoted below:

(b) Except for a segment that is trimmed to clear obstructions, or lengthened to provide red sheeting near red lamps, each white or red segment shall have a length of 300 mm ±150 mm.

(c) Neither white nor red sheeting shall represent more than two thirds of the aggregate of any continuous strip marking the width of a trailer, or any continuous or broken strip marking its length.


Width – DOT certified tape can be 2″ wide, 3″ wide or 4″ wide. The most popular and cost efficient size is 2 inches but for larger trucks many users prefer the 3 and 4 inch widths in either the 6/6 or 7/11. The more visible the truck the better. Also, in the event of an accident it is important to be able to show due diligence when it comes to vehicle conspicuity.  The specific regulation is as follows:

(d) Retroreflective sheeting shall have a width of not less than 50 mm (Grade DOT-C2), 75 mm (Grade DOT-C3), or 100 mm (Grade DOT-C4).


Reflectivity & Performance – This is one of the most important aspects of this tape.  A bright tape can be seen from longer distances.  For highway applications this is very important.  To meet the DOT C2,3,4 requirements a tape must meet all the requirements for ASTM D4956-90 Type V Sheeting EXCEPT for the reflectivity.  These requirements would include things like adhesion, colorfastness, flexibility, shrinkage,  weathering, etc… Reflectivity requirements are basically equal to Type III or High Intensity Glass Bead tape.  To be safe, a Prismatic DOT tape is recommended.  This will assure that the reflectivity far exceeds the minimum requirements.  The exact wording of the regulation and a reflectivity chart are included below:

S5.7.1.2 Performance requirements. Retroreflective sheeting shall meet the requirements of ASTM D 4956–90, Standard Specification for Retroreflective Sheeting for Traffic Control, for Type V Sheeting, except for the photometric requirements, and shall meet the minimum photometric performance requirements specified in Figure 29.

(e) The coefficients for retroreflection of each segment of red or white sheeting shall be not less than the minimum values specified in Figure 29 of this standard for grades DOT-C2, DOT-C3, and DOT-C4.

Figure 29—Minimum Photometric Performance of Retroflective Sheeting in Candela/Lux/Square Meter

Entrance angle Observation angle Grade
0.2 Degree 0.5 Degree
White Red White Red
-4 degree 250 60 65 15 DOT–C2
30 degree 250 60 65 15 DOT–C2
45 degree 60 15 15 4 DOT–C2
-4 degree 165 40 43 10 DOT–C3
30 degree 165 40 43 10 DOT–C3
45 degree 40 10 10 3 DOT–C3
-4 degree 125 30 33 8 DOT–C4
30 degree 125 30 33 8 DOT–C4
45 degree 30 8 8 2 DOT–C4

DOT Certification Logo – The DOT-C2 designation is to appear on the tape at least every 12 inches.  The characters should be at least 3 mm tall and stamped in indelible ink or an equivalent.  The exact wording is below:

S5.7.1.5 Certification. The letters DOT-C2, DOT-C3, or DOT-C4, as appropriate, constituting a certification that the retroreflective sheeting conforms to the requirements of S5.7.1.2, shall appear at least once on the exposed surface of each white or red segment of retroreflective sheeting, and at least once every 300 mm on retroreflective sheeting that is white only. The characters shall be not less than 3 mm high, and shall be permanently stamped, etched, molded, or printed in indelible ink.


Flexible High Intensity Reflective Tape – SOLAS Alternative

Flexible high intensity reflective tape is a glass bead product that utilizes a polyester topcoat to allow the tape to stretch and conform to flexible surfaces. Some examples of these surfaces would be a traffic cone, a road barrel or a kayak. Also, rain suits and zodiacs.

The flexible high intensity tape is a type 3 or otherwise know as an ASTM 4956 -03 tape.  It uses high index beads that are encapsulated in a honey comb pattern.  This renders the tape about 3 times more reflective than standard engineer grade or type 1.

The best feature of the flexible high intensity type 3 tape is its ability to stretch.  If a traffic cone or road barrel is hit by a car the tape will rebound with the object it is on.  Thence its other name “reboundable reflective tape”.  There are a variety of application where this ability to stretch comes is desirable.  Curves surfaces such as a helmet can be striped with this material since it will stretch and lay down.  Other stiff tapes will not work on complex curves.

We call this a SOLAS alternative because there are some manufacturers who use this type of tape as SOLAS tape.   It is very bright for a glass bead tape and will flex in marine applications.   It would be just like a SOLAS glass bead tape but without the SOLAS logo on it.

We have more information on this tape as well as an online store at www.colebrothers.com .

Custom Die Cut Reflective Shapes or Overlays (CAD Cut)

Custom Designed Die Cut or CAD Cut Reflective Shapes online store

Reflective tape is readily available in sheets and rolls.  However, for many applications a particular shape is needed to solve a night time visibility issue.  For example, the spaces between diamond plate can be made reflective by using a shape that fits the area between the diamonds.  The back of an iphone can be made reflective by custom cutting a shape that fits.  We have several shapes and sizes pre priced at www.reflectiveshapes.com .   However, the shapes that we can design and cut are unlimited.

The job pictured below is going on a fire truck.  To have a custom shape designed and cut you would simply send the actual object to use as a template or send a tracing of the shape that you want.  A sample would be designed and mailed out as a proof if necessary.  Once the shape is verified we would begin cutting them in volume.  Pricing varies depending on complexity and amount of material used.  For example, the shapes to the left are about 3.5″ square and run 50 cents each.  In some cases design time is free and in others there is a charge.  The size of an order and the complexity of the design are both factors in this cost.

Letters and numbers can also be cut in volume.  We use Reflexite’s V98 series reflective sheeting for all of our shapes.  This material is conformable and repositionable making it very easy to work with.  It is prismatic and very bright.  At the present time we carry white, blue, red and fluorescent lime yellow and fluorescent orange.