An Alcohol Breathalyzer is a device for estimating blood alcohol content (BAC) from a breath sample. Breathalyzer is the brand name of a series of models made by one manufacturer of these instruments, later sold to National Draeger), but has become a genericized trademark for all such instruments. In Canada, a preliminary non-evidentiary screening device can be approved by Parliament as an approved screening device, and an evidentiary breath instrument can be similarly designated as an approved instrument. The U.S. National Highway Traffic Safety Administration maintains a Conforming Products List of breath alcohol devices approved for evidentiary use, as well as for preliminary screening use.
There are many models of consumer or personal breath alcohol testers on the market. These hand-held devices are generally less expensive than the devices used by law enforcement. Many consumer breath testers use semiconductor-based sensing technology, which is both less expensive and less accurate and reliable than fuel cell or infrared devices. While these devices can sense the presence of breath alcohol, they do not provide reliable measures of BAC. Semiconductor devices are also more prone to false positives, i.e., they can signal alcohol even when none is present.
More recently, manufacturers have begun to introduce consumer breath testers that use the same platinum fuel cell technology as used in law enforcement portable breath testers. Some public breath alcohol testers use fuel cell sensors as well, which encourage their higher accuracy and longer reliability than with semiconductor testers. Fuel cell testers are more expensive than semiconductor models; however, they are also more precise, reliable and accurate. Another advantage of all fuel cell devices is that they are less prone to false positives than are semiconductor devices.
All breath alcohol testers sold to consumers in the United States are required to be certified by the Food and Drug Administration, while those used by law enforcement must be approved by the Department of Transportation's National Highway Traffic Safety Administration.
Manufacturers of over-the-counter consumer breathalyzers must submit an FDA 510(k) Premarket Clearance to demonstrate that the device to be marketed is at least as safe and effective, that is, substantially equivalent, to a legally marketed device (21 CFR 807.92(a)) that is not subject to Premarket Approval (PMA). Submitters must compare their device to one or more similar legally marketed devices and make and support their substantial equivalency claims.