Biometric Locks Mysteries, What Is FRR?

In the world of biometrics, not all issues are created exactly equal. For instance, a biometric door lock which frequently gives false positives may admit someone who should not have access to whatever the equipment is protecting. On the other hand, when biometric locks falsely rejects input which should be matched with information in the database, it does not have to be disastrous. After all, it is only preventing access to something which you have deemed important enough to safegard.

This false negative, known as a false rejection, is measured by a ratio which compares false rejections to overall access attempts (false rejection divided by total attempts).  False rejection rate, or FRR, is typically specified in product information as a fraction or ratio.

When reading the product description of biometric locks, a false rejection rate of “< 1/100” indicates that there will be less than one false rejection in every one hundred attempts, or a 1% FRR. While you would desire the FRR of your biometric door locks to be as close to zero as possible, a rate up to one percent is considered acceptable.

What Causes False Rejection?

Unlike false acceptances which occur because of software or hardware issues, false rejection typically occurs because a setting is too sensitive or because of human error. For biometric locks which have a higher FRR, you can adjust the sensitivity of the machine so the parameters are not quite so rigid. Beware that doing so could cause your system to register more false positives, however.

For systems which read physiological characteristics such as facial structure, optical make up or fingerprints, it is important for you to position your body so the scanner can work correctly.

If you do not, this can result in a false negative. Some people may not realize how important it is to follow instructions about machine usage.

If you are an authority figure, it is important to educate those around you about the biometric locks you use.

The accepted “quick fix” to false rejection is simply for you to try again. It is similar to entering your PIN or password incorrectly; you simply enter again when prompted. Many times, this is the only solution which is needed in response to a false rejection.

If you have adjusted sensitivity of your biometric door locks and are informed about how to correctly use it but still experience problems, it may be time for you to invest in higher quality equipment.

By reading the product specification for the FRR and seeking out reviews of the system, by people who have experience with it, you can make an educated decision about your purchase.