There are three common film types now used by utilities, and all have very different properties. Two are based on reflective beads and the third is prismatic. The Engineer Grade ("RE" & "RL") reflective digits have been the industry standard over the last 30 years. In 1985, we introduced the 3M High Intensity digits ("RI") and in 1991, we introduced SunBright® High Intensity digits ("SB"). SunBright® markers appear much brighter by day other than High Intensity or Engineer Grade reflective digits. They are true yellow, not a muddy orange. To analyze the nighttime visibility, take the digits out at night and shine a low wattage flashlight on them. The SunBright® digits remain the brightest, although the 3M high intensity film is also appreciably brighter than Engineer Grade. Note human vision of reflective films is not linear; a film having a candle-power of 3X more than another subjectively only appears 50% brighter.
 
 

		SunBright® markers (left) are brighter by day, as well.
		Reflective sign using 3M's high intensity film is over 15 years old. It faces south in Florida, which is one of the harshest environments in the US.
				Reflective markers use the same material used in street signs. US Department of Transportation field testing of the films and adhesives used in our tags showed no significant loss of adhesion over a 17 year period. In fact, the adhesive holding power actually increased.

Material & Vendor	Code	Mfg,s Specified Outdoor Life	Type	CandlePower (.2/-.4), Typical	Mat'l Cost from Film Mfg	Life Cycle Cost
3M 3271	RE	7 years	beads, Engineer Grade	50	29%	118%
3M 5271	RL	3 years	beads Engineer Grade low temp.	50	43%	290%
3M 580-71	RC	7 years	beads, Commercial Grade	60	60%	135%
3M 3871	RI	10 years	beads, High Intensity Grade	170	100%	100%
3M 5871	RM	7 years	beads, High Intensity Grade low temp.	170	109%	149%
Sunbright®   HIS	SB	10 years	prismatic, High Intensity Grade standard.	290	91%	96%
3M 3917G	RQ	7 years	prismatic, Diamond Grade	660	129%	159%

 
Also see:

Also see:

• Fluorescent Reflective Signs
• School Crossing Signs
• Traffic Signs
• No Parking Signs