This document explains when and how to use alcohol breathalysers in alcohol and other drug (AOD) settings.

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Clinical AOD treatment services may at times need to assess a client’s recent alcohol use for the purpose of informing treatment and monitoring outcomes. In most circumstances clinicians are to use their clinical judgement and assessment skills to identify if a client is intoxicated or affected by alcohol. In addition, there are limited circumstances in which use of a breathalyser is appropriate, as set out below.

Infection prevention and control measures will minimise the risk of transmitting COVID-19 or other infections when a client uses a breathalyser. There is no evidence that any infection, including COVID-19, is transmitted by alcohol breathalyser devices if those devices are used correctly.

Breathalyser devices operate in two modes: passive or active. Passive mode requires the client to speak closely to the device but not contact it directly. Passive mode detects the presence or absence of alcohol but not alcohol concentration. Active mode requires the client to blow into a disposable mouthpiece and records alcohol concentration. Services may choose to use active mode and/or passive mode.

Indications for using a breathalyser

In addition to meeting one of the limited indications for breathalyser use listed below, clinicians must obtain approval for breathalyser use from a senior clinician.

The use of breathalysers is to be restricted to the following indications:

  1. A clinician intends to start diazepam loading of a client for withdrawal treatment;
  2. A clinician has concerns about disulfiram medication dispensing (e.g. the client reports or is assessed as having potentially used alcohol recently);
  3. A clinician has significant concerns about the safety of opioid agonist treatment administration;
  4. A senior clinician determines that obtaining a breathalyser reading is clinically indicated to guide treatment as ordered by a doctor; and/or
  5. To assist in assessment of a client where the senior clinician determines that a breathalyser reading will add value. 


​Clinicians who use a breathalyser are to adhere to the instructions below.

  1. Health workers are to maintain a safe distance while conducting testing.
  2. The Clinician must apply standard precautions and hand hygiene when conducting breath testing. 
  3. Where a client is confirmed or suspected to have COVID-19 or undiagnosed acute respiratory infection (ARI) health workers are to wear a fit checked P2/N95 respirator and eye protection and gown when within 1.5m of a client. 
  4. In all other cases a surgical mask and eye protection are to be worn when within 1.5m of the client. Glove use is optional depending on the assessment of risk of body fluid contact assessment.
  5. The clinician is to instruct the client to wash their hands before and after use of the breathalyser, or if hand washing is not practical, to use alcohol-based hand rub. 
  6. A breathalyser is assigned to a client for the duration of that service encounter. The breathalyser is then to be cleaned according to the requirements set out in Infection prevention and control below.
  7. A two-stage process for taking a breath test reading from clients is recommended. This involves using the breathalyser in passive mode in the first instance to detect whether alcohol has been consumed. The active mode breathalyser is only needed to be used if the passive mode detects the presence of alcohol and is necessary to know the alcohol concentration. Note that for some indications, detecting the presence of alcohol is enough and there will be no need for a second test. For example, the presence of any concentration of alcohol is sufficient to not administer disulfiram.
  8. Passive mode

  9. The clinician wearing appropriate personal protective equipment (PPE) demonstrates to the client how to start the breathalyser reading in passive mode (press the arrow button on the R hand side). After passing the breathalyser device to the client in the “passive mode”, the clinician is to move away to a distance of 1.5 metres.
  10. The client holds the device themselves and conducts the passive test according to the clinician’s instructions:
    • ask the client to press the start button
    • speak / count to 10 directly into the machine
    • wait until the breathalyser device makes a noise/bleep once recorded reading
    • show the clinician the result.
  11. If the result of the passive test indicates: 
    • alcohol is present; the clinician decides whether the breath alcohol concentration, assessed by breathalyser reading in active mode, is required. 
    • alcohol is not present; device is cleaned as described in Infection prevention and control below.
  12. If a breath alcohol concentration is required and the breathalyser being used has active (standard) mode (using the mouthpiece), the same breathalyser should be used to obtain that reading.
  13. Active mode

  14. The active test should be conducted at least 1.5m away from others, where possible or practical. If not, find a suitable room that is well ventilated and away from other clients/patients.
  15. The clinician, wearing appropriate PPE, shows the client how to use the breathalyser.
  16. The clinician removes themselves from the room, or moves at least 1.5 metres away from the client, until the client has conducted the active breath test.
  17. The clinician, if testing is being conducted in a separate room, returns to the room and the client shows the clinician the test result.
  18. Mouthpieces can be disposed of in general waste bins, unless the client is a confirmed COVID-19 case, in which case the tube should be placed in the clinical waste bin.
  19. Both the client and the clinician are to perform hand hygiene after disposing of mouthpieces.  
  20. The clinician cleans the device according to the requirement.
On every occasion that a breathalyser is used, the indication, the approval, the outcome and the intervention is to be documented in the client’s clinical notes.

Infection prevention and control

Following use of the breathalyser, the reusable parts of the device are to be cleaned and disinfected according to the manufacturer’s instructions for use, e.g. with Clinell Universal™ wipes. Ensure standard infection prevention and control processes are applied when undertaking cleaning, including:

  • perform hand hygiene before and after procedure
  • wear appropriate PPE 
  • clean all reusable shared items and frequently touched surfaces with Clinell Universal wipes 
  • Dispose of waste into general waste stream or clinical waste stream according to its exposure to body fluids. Mouthpieces used by clients with COVID-19 and any items contaminated by body fluids are to be disposed of in the clinical waste stream.

Traces of alcohol from cleaning wipes may alter readings. To mitigate this, allow the device to dry for at least 15 minutes after cleaning (or as indicated in the manufacturer’s instructions for use).

For more information refer to CEC COVID-19 Infection Prevention and Control Manual and CEC Infection Prevention and Control Practice Handbook



These procedures have been adapted from the South East Sydney Local Health District Drug and Alcohol Services ‘Indications and process for using breathalysers during the COVID-19 Pandemic’ Interim Procedures. We gratefully acknowledge their original work. The process has been reviewed by the Centre for Alcohol and Other Drugs, NSW Health, and the Clinical Excellence Commission. 

Document information

Developed by

Centre for Alcohol and Other Drugs, NSW Ministry of Health.


Drug and Alcohol Services, South Eastern Sydney Local Health District.

Endorsed by

Dr Nigel Lyons, Deputy Secretary, Health System Strategy and Planning, NSW Ministry of Health.

Reviewed by

Infection Prevention and Control, Clinical Excellence Commission.

For use by

NSW drug and alcohol treatment services​.​​

Current as at: Tuesday 30 August 2022
Contact page owner: Health Protection NSW