Firstly and most importantly, the color of a nitrile glove doesn’t have anything to do with the quality of protection offered by the glove.
While there are no absolute standards for color, traditionally a blue nitrile glove has been used to differentiate non-latex from latex gloves. This is now the case mostly due to industry preference. The visual distinction adds a level of safety, preventing mistakes that could result in harmful reactions for patients with latex allergies. Most medical facilities still use shades of blue, but other colors such as grey, purple, and pink nitrile gloves are used as well.
Black nitrile gloves are the preferred glove of law enforcement and postal workers, who can use black nitrile gloves to trace white powers and residues. Orange nitrile gloves are used in many applications that take place in dark confined spaces where visibility is crucial, such as an auto mechanic.
Double gloving is a practice used to recognize glove failure. Wearing two gloves of differing colors over top of each other helps alert medical professionals when glove integrity has been breached when the underlying color becomes visible.
The Halyard BLACK-FIRE Nitrile Exam Glove is a reversible glove that is orange on one side, black on the other, and uses a proprietary QUICK CHECK technology that serves the same purpose as double gloving, which can be lifesaving in situations like dealing with fentanyl. BLACK-FIRE nitrile gloves are fentanyl tested and no permeation occurred after 240 minutes to exposure.
Ultimately, color comes down to personal preference. Blue remains the standard for designating the synthetic latex nitrile glove, but the practice of color coding is becoming increasingly popular in medical facilities for distinguishing between vinyl, latex and nitrile gloves.