Retro-reflective tapes come in various types, each tailored for specific purposes, with differences in adhesion, flexibility, conformability, and brightness based on the brand and type. This article explores the photometric properties of several tapes by measuring their reflectivity using a retro-reflectometer. This device quantifies the amount of light returned by a reflective film at different angles. Our study measures reflectivity at 0-degree and 30-degree angles to assess the tape’s performance when struck perpendicularly and at an angle, simulating real-world driving conditions.
Much like automobile headlights, the higher the candela reading from a section of retro-reflective tape, the greater the distance from which it can be seen. In traffic scenarios, brighter reflective tapes visible from further away provide earlier warnings to drivers, allowing more time to react.
IMPORTANT NOTE: Different retro-reflectometers can yield varying brightness measurements depending on calibration and the specific instrument used. Readings can fluctuate between samples. The goal of this study is not to determine the exact brightness of each film but to compare them and discuss their pros and cons. It also aims to contrast entrance angles to identify which films reflect the brightest at each angle. All measurements were taken with the same retro-reflectometer, one at a time, within a specified period, using 0-degree and 30-degree entrance angles.
Definitions:
- Candelas / Lux / Square Meter: A unit of luminous intensity expressed as one candela in one second of light emission per square meter of area. This unit measures the brightness intensity of retroreflective sheeting and other lighting, and is used to set minimum standards for reflectivity.
- Entrance Angle: The angle between the illumination axis and the retroreflector axis, i.e., the angle at which light enters a retro-reflective film. At a perpendicular 0-degree angle, reflectivity is at its highest. Specification sheets measure maximum reflectivity at a 4-degree entrance angle. At a 15-degree entrance angle, retroreflectivity often reduces by approximately 20%. At 30 degrees, reflectivity often drops by approximately 50%. At 45 degrees, reflectivity often drops by approximately 85%. And at a 60-degree entrance angle, retroreflectivity often reduces by 86–99%, depending on the tape type and brand.
(Note: Our readings are for comparison purposes only; readings differ with various retro-reflectometers. Our tests are for comparison purposes only. The readings below are not intended to pinpoint the exact reflectivity of each film.)
Study Results – Table:
| Reflective Tape Name & Type | 0 Degree | 30 Degree | % diff – 0 to 30 |
| Nikkalite Flexible Engineer Type 1 | 86.0 | 43.4 | 49.5% Decrease |
| Oralite 5650 RA Engineer Type 1 | 81.0 | 49.8 | 38.2% Decrease |
| 3M 680 CR Engineer Type 1 | 63.0 | 27.9 | 55.5% Decrease |
| Nikkalite Super Engineer Type 2 | 166.7 | 76.7 | 53.9% Decrease |
| Nikkalite High Intensity Type 3 | 222.8 | 241.7 | 8.5% Increase |
| Nikkalite Flex Hi Intensity Type 3 | 245.4 | 256.8 | 4.8% Increase |
| 3M 3930 HIM Prismatic Type 4 | 574.5 | 368.2 | 35.8% Decrease |
| Avery HIP Prismatic Type 4 | 449.2 | 143.5 | 68.1% Decrease |
| Nikkalite HIM Prismatic Type 4 | 629.8 | 454.8 | 27.8% Decrease |
| Oralite 5900 HIP Prismatic Type 4 | 653.8 | 313.9 | 52.0% Decrease |
| Oralite 5930 Prismatic Type 4 | 415.9 | 170.0 | 59.1% Decrease |
| Oralite 5934 Prismatic Type 4 | 691.1 | 269.1 | 61.0% Decrease |
| Oralite V82 Metalized Prismatic Type 5 | 1070.9 | 583.3 | 45.5% Decrease |
| 3M 4000 DG3 Prismatic Type 11 | 628.4 | 161/305* | 74.3/51.4% Dec. |
| Avery 11500 Omnicube Type 11 | 621.2 | 150/165* | 75.8/73.4% Dec. |
| Oralite 9000 Prismatic Type11 | 749.8 | 407.9 | 45.6% Decrease |
| 3M 983 Diamond Grade | 797.7 | 487.8 | 38.9% Decrease |
| 3M 983 DOT C2 Truck Tape | 786.7 | 542.3 | 31.0% Decrease |
| 3M 983 FRA Tape | 789.6 | 548.9 | 30.4% Decrease |
| 3M RGA Rail Gate Arm Tape | 648.1 | 339.9 | 47.5% Decrease |
| Oralite V98 Vehicle Conspicuity | 627.1 | 322.5 | 48.6% Decrease |
| Oralite V92 Vehicle Conspicuity | 629.3 | 317.3 | 49.6% Decrease |
| Oralite V92 DOT C2 Truck Tape | 635.8 | 300.7 | 52.8% Decrease |
| Oralite V82 Type 5 DOT C2 | 823.1 | 354.1 | 56.9% Decrease |
| Oralite FRA Rail Car Tape | 789.6 | 403.1 | 48.9% Decrease |
| Oralite RGA Rail Gate Arm Tape | 828.5 | 378.0 | 54.3% Decrease |
| Oralite Marine SOLAS Tape | 1078.0 | 476.4 | 55.8% Decrease |
| Oralite Photo Electric | 1407.8 | 771.1 | 45.2% Decrease |
Study Results – Images:
Engineer Grade Retro Reflective Tapes – Type 1 (Oralite, 3M™, Nikkalite):
We conducted tests on three brands of engineer-grade type 1 reflective tapes. The Nikkalite ELG Flexible Engineer Grade, the least expensive and most conformable, achieved the highest rating at a 0-degree entrance angle. Oralite’s 5650 Rapid Air recorded the second-highest candela rating overall and the highest at a 30-degree angle. In contrast, the 3M™ 680 CR, the most costly of the three, had the lowest candela readings at both 0 and 30-degree entrance angles. Despite these variations, all three tapes are of high quality and have long-lasting outdoor durability. (Note: We intend to retest 3M 680 CR with a different sample to confirm our findings.)
Super Engineer Grade Glass Bead Tape – Type 2 (Nikkalite)
Based on our research, only one Super Engineer Grade film is currently available in the United States. Nikkalite claims it to be twice as bright as standard engineer-grade films while maintaining similar fundamental properties of engineer. The increased brightness of super engineer type 2 is achieved through the use of higher index glass beads. Our retro-reflectometer tests confirm that Super Engineer Grade is nearly twice as bright as the average engineer grade type 1, without any noticeable difference in appearance or texture. Additionally, it is easily cut with a plotter and printable. Essentially, this enhanced brightness allows the film to be visible from twice the distance compared to standard films.
High Intensity Type 3 Glass Bead (Nikkalite)
We conducted reflectivity tests on this film and recorded 222 candelas for the standard high-intensity version and 245 candelas for the flexible version, aligning with our expectations. However, what stood out was that when the entrance angle increased from 0 to 30 degrees, the tapes reflected 4-8% more light. This performance is unique among the tapes we tested, as most reflective tapes typically lose about 50% of their brightness at a 30-degree angle. Surprisingly, Nikkalite high-intensity type 3 tapes actually become brighter at this increased angle.
The explanation lies in the construction of Type 3 glass bead tapes, which encapsulate high-index glass beads within individual cells. These beads create a dome under the transparent colored topcoat. This dome structure enables the tape to reflect light effectively both at an angle and perpendicularly, and in this case, even better at an angle. With candela readings around 250, Type 3 tapes are visible from greater distances than Type 1 or Type 2 tapes.
High Intensity Prismatic – Type 4 (3M , Avery , Oralite , Nikkalite)
High Intensity Type 4 Prismatic Tapes have surpassed Type 3 glass bead films in popularity for road signs and similar applications due to their enhanced brightness and durability. We evaluated four brands of HIP: one from each of 3M, Avery, and Nikkalite, and three from Oralite.
3M 3930 High Intensity Prismatic is the most widely used film for road signs in the United States. It retains reflectivity at wide angles, with only a 35.8% reduction at a 30-degree angle. While it is not the brightest Type 4 film in our tests, it provides ample reflectivity and ranks second in brightness at a 30-degree angle.
Avery HIP showed good brightness but tested as the second lowest at a 0-degree angle and the lowest at a 30-degree angle.
Nikkalite HIM films recorded the highest readings at a 30-degree angle and the second highest at a 0-degree angle.
Orafol manufactures several Oralite Type 4 films for different purposes. We tested three: 5900, 5930, and 5935. The 5900 and 5935 films achieved the highest candela readings among all Type 4 films at a 0-degree entrance angle. The Oralite 5930 reflective tape, intended for work zones, performed similarly to Avery.
Type 5 Prismatic Reflective Tapes (Oralite)
We evaluated Oralite’s V82 Type 5 prismatic metalized reflective tape and were highly impressed by its reflectivity at both 0-degree and 30-degree entrance angles. With candela readings of 1070 and 538, respectively, V82 is an exceptionally bright film. Made with Oralite’s AP1000 sheeting, this film is very thin and flexible, though it does not stretch or conform, making it suitable for flat or single-curved surfaces like bollards. Among the films we’ve tested, Oralite V82 and its sister film, Oralite SOLAS, offer the greatest visibility distance.
Type 11 – Ultra High Intensity Prismatic Sign Sheeting
Type 11 retro-reflective sheeting represents the latest advancement in retro-reflective technology. While primarily designed for overhead highway signs, it is versatile enough for various other applications. Some brands use full cube corner prisms, while others employ deep standard cube corner prismatic arrays. We tested products from 3M, Avery, and Oralite.
3M DG3 4000 series recorded a reflectivity of 628.4 candelas at a 0-degree angle. This film uses full cube prisms, which results in varying reflectivity depending on the orientation. When the prisms are oriented sideways, the 30-degree reflectivity is 628.4 candelas. However, when oriented vertically, the 30-degree reflectivity drops to 305.7 candelas. This allows for the flexibility to adjust material orientation to best suit specific applications.
Avery 11500 series OmniCube material was also tested. Avery designs this film with prism arrays oriented so that 50% are horizontal and 50% are vertical, eliminating reflectivity changes due to orientation. However, this results in lower overall reflectivity. At a 0-degree angle, the film reflects 621.2 candelas. At a 30-degree angle, regardless of orientation, the reflectivity ranges between 150 and 165 candelas.
Finally, we tested Oralite’s 9000 Series Type 11 film. Although it does not use full cube technology, it proved to be the brightest Type 11 film we tested. At a 0-degree angle, it recorded a reflectivity of 749.8 candelas, and at a 30-degree angle, it achieved 407.9 candelas. This film demonstrated exceptional brightness at both angles, making it a high-quality option.
Specialty Reflective Tapes (3M , Oralite)
There are numerous specialty reflective tapes designed for unique applications, many of which are regulated and must meet specific characteristics. Among these, Oralite V82 DOT, RGA, and SOLAS tapes exhibit the highest reflectivity at a 0-degree angle. The 3M 983 series films are just slightly less reflective at this angle. However, 3M tapes, particularly the Diamond Grade series, perform exceptionally well at a 30-degree angle, surpassing Oralite in brightness. The highest reflective tape we tested was Oralite’s special Photo Electric film. As illustrated in the chart below, all these specialty tapes demonstrate remarkable brightness.
| Reflective Tape Name & Type | 0 Degree | 30 Degree | % diff – 0 to 30 |
| 3M 983 Diamond Grade | 797.7 | 487.8 | 38.9% Decrease |
| 3M 983 DOT C2 Truck Tape | 786.7 | 542.3 | 31.0% Decrease |
| 3M 983 FRA Tape | 789.6 | 548.9 | 30.4% Decrease |
| 3M RGA Rail Gate Arm Tape | 648.1 | 339.9 | 47.5% Decrease |
| Oralite V98 Vehicle Conspicuity | 627.1 | 322.5 | 48.6% Decrease |
| Oralite V92 Vehicle Conspicuity | 629.3 | 317.3 | 49.6% Decrease |
| Oralite V92 DOT C2 Truck Tape | 635.8 | 300.7 | 52.8% Decrease |
| Oralite V82 Type 5 DOT C2 | 823.1 | 354.1 | 56.9% Decrease |
| Oralite FRA Rail Car Tape | 789.6 | 403.1 | 48.9% Decrease |
| Oralite RGA Rail Gate Arm Tape | 828.5 | 378.0 | 54.3% Decrease |
| Oralite Marine SOLAS Tape | 1078.0 | 476.4 | 55.8% Decrease |
| Oralite Photo Electric | 1407.8 | 771.1 | 45.2% Decrease |
