By what it shows you
Digital alcohol testers
A digital tester shows the reading as a number on a screen rather than a colour or a row of lights. That is the whole difference, and it is the reason to buy one: a number can be written down, repeated and compared. The four below all use a semiconductor sensor and respond in about five seconds.
4 models, 
3,000 to 6,000, excluding tax. Full price list
| Model | Sensor | Detection range | Response | Price (excl. tax) |
|---|---|---|---|---|
| A20 SMART | High-Precision Semiconductor Sensor | 0.00–200 mg/100mL | 5 Seconds | 3,000 |
| A15 CSY | Semiconductor sensor | 0.00–0.19% BAC (0.0–1.9 g/L) | Less Than 5 Seconds | 4,000 |
| A17 METAL | Semiconductor Sensor | 0.00–0.19% BAC (0–1.9 g/L) | Less Than 5 Seconds | 4,500 |
| ARD 600 | High-Precision Semiconductor Sensor | 0.00–0.19% BAC (0–1.9 g/L) | Less Than 5 Seconds | 6,000 |
Every figure here is read from the product's own page. Where a product does not publish a number, this table says so rather than estimating it.
What the number is in
Three of the four read in %BAC and g/L; the A20 SMART reads in mg/100mL, and the ARD-600 can show all four units. If readings are being written into a register, pick the unit the register already uses rather than converting by hand.
When to step up
A semiconductor sensor drifts with use and is recalibrated to correct it. A fuel cell sensor holds its reading longer. If a result will be recorded or questioned by somebody else, start at the AH3 instead — it is the cheapest fuel cell unit in the range.
Questions
- What does a digital alcohol tester actually show?
- The reading as a number on the screen. Three of these four read in %BAC and g/L, the A20 SMART reads in mg/100mL, and the ARD-600 can display %BAC, g/L, mg/L and mg/100mL.
- How quickly does it give a result?
- All four respond in about five seconds, with a ten-second warm-up on the A15 CSY, A17 Metal and ARD-600. Each product page lists its own warm-up, response and recovery times.
- Does it need recalibrating?
- A semiconductor sensor drifts with use, and recalibration is what corrects it. The calibration cycle is listed on each product page; our calibration service page explains how it is done.
- Can several people use the same unit?
- Yes, with a fresh mouthpiece for each person.