Personal Breathalyzers

Choose based on accuracy (look for fuel cell sensors), calibration requirements, detection range (lower BAC sensitivity for early detection), form factor (keychain vs handheld), and additional features like mobile app connectivity or memory recall

Fuel cell sensors are generally more accurate and stable for measuring blood alcohol concentration (BAC) and are used in professional-grade devices, while semiconductor sensors are cheaper and less precise, better suited for casual, low-cost screening

Most breathalyzers with fuel cell sensors require calibration every 6 to 12 months or after a specified number of tests; calibration typically ranges from a modest service fee to higher costs depending on the manufacturer and whether you mail the unit in or use a local service

Accuracy varies by sensor type and quality; fuel cell units can provide reliable BAC estimates when used properly. Readings can be affected by mouth alcohol (recent drinking, mouthwash), device warm-up/calibration, user technique, and environmental factors like temperature

Personal breathalyzer readings are generally not accepted as legal evidence; law enforcement uses calibrated, certified devices and standardized procedures for legal BAC determination

Keep the sensor and mouthpiece clean, avoid exposure to extreme temperatures, replace batteries or recharge per manufacturer guidance, and follow the recommended calibration schedule to maintain accuracy

Personal breathalyzers range from budget models under $50 with semiconductor sensors to higher-quality fuel cell units commonly in the $50–$300 range; average prices in some marketplaces are around the low hundreds for mid-tier units