Evidential breath alcohol measurements in South Africa

Transcription

1 Evidential breath alcohol measurements in South Africa 27 July th APMP workshop Mongolia Mudalo Isabel Jozela TQM

2 Statistics o Driving under the influence of alcohol is a criminal offence o According to WHO South Africa consumes litres of pure alcohol (2014), ranking them as the African country who consumes the most alcohol per capita 1755 Killed in Road Crashes in South Africa during 2015 Festive Season (1 December 2015 to 11 January 2016) (Released date 12 January 2016 by RTMC) Major contributor: Drunk and driving Over 6000 motorists were arrested for drunk and driving during 2015 Festive Season

3 Applications Law Enforcement Construction sites Professional driving Manufacturing Mining

4 History Evidential breath analysers (EBAs) were introduced in 1997 NMISA has been responsible for calibration since 1997 Around 400 instruments were calibrated per year Dry and wet calibration method NMISA was responsible for the dry gas calibration

5 Dry gas calibration 1 Certification of secondary reference gas standards Locally made secondary reference NDIR PRGM

6 Dry gas calibration 2 Secondary reference gas standards used for calibration Calibration range 0,2 mg/l to 0,8 mg/l Ten measurements of each reference gas Dedicated gas port Measuring principle -Infrared at wavelength of 9µm

7 Dräger models Dräger Alcotest 7110 Evidential Dräger Alcotest 9510 Evidential onwards

8 Legislation o National Traffic Act 93 of 2006 The breath alcohol limit :- 0,24 mg/l for all drivers and 0,10 mg/l of breath for professional drivers o Legal Metrology act o SANS 1793 Requirements of EBA calibration

9 Evidential breath analyser (EBA) Measures the mass concentration of ethanol by analysing deep-lung air (exhaled air) EBAs shall be capable of expressing measurement results in terms of ethanol content in the exhaled breath Measurement unit as per SANS 1793 is mg/l The relationship between the blood alcohol content and the breath alcohol composition is governed by Henry s law "At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid TQM

10 Case Study real case Hendriks Court case 2011 Accused breath alcohol concentration- 0,95 mg/l measured using Dräger Alcotest MKIII 7110 Reliability of the instrument was in question Problems identified were; Reliability -accurate determination of the alcohol concentration in the breath Calibration of the instrument used Training of the traffic officers for the correct use of the instrument, documentation of charge dockets, maintenance of the instrument Tampering with the instrument after calibration Recommendation from the case; Temperature of the exhaled breath should be measured. Test subject should blow two times before the instrument provides a final result Outcome This led to the re-establishment of the technical working group for drug and alcohol testing for the revision of SANS 1793 New evidential breath analyzer was produced by Dräger and currently the only EBA allowed in South Africa TQM

11 Role players National prosecuting authority (NPA) Prosecution Ensures that perpetrators of crime are charged and held responsible National Metrology Institute of South Africa (NMISA) Metrology Underpins testing and calibration through measurement accuracy & traceability Calibration of EBA National Regulator for Compulsory specifications (NRCS) Regulation Administrates regulation to ensure compliance and protect human health and safety Granted approval and Drager 9510 EBA in South Africa South African bureau of Standards (SABS) Standardization Documentary standards for validated methods used in industry SANS 1793:2013 Technical working group for drug and alcohol testing Department of transport Law enforcement Road safety Regulation of transport sector

12 Improvements (New vs Old) Heated mouth piece For accurate determination of breath alcohol Breath temperature compensation BAC- Breath alcohol concentration at 34 0 C Next calibration date be added after calibration Improved sealing and packing after calibrationcalibration void if seal is broken stickers Instruments sent straight to the department after calibration by NMISA The new SANS addresses all the improvements mentioned

13 New EBA Dräger Alcotest 9510 new features Introduced in 2015 in South Africa Wet calibration done using ethanol CRMs It has a Heated breath 0 C Calibration/blowing done using breath hose and mouthpieces Using water bath and breath simulators

14 Calibration of the instrument Calibration process Three certified solutions of ethanol are used: 0,2 mg/l, 0.4 mg/l and 0.8 mg/l according to new SANS 2013 document Traceable to the NMISA organic laboratory Breath hose and mouth piece are connected to the water bath/breath simulator Water Bath/ breath simulator Simulators at kept at 34 o C Mouth Piece Breath hose

15 Calibration certificate Mass concentration of ethanol in air using the Dubowski s equation Mass concentration of aqueous ethanol (mg/l) Temperature of the bath ( C) Mass concentration of ethanol in air (mg/l) Certificate number 619,3 32 0,211 Batch 0250/15 981,8 37 0,465 Batch 0251/ ,0 34 0,804 Batch 0252/15 C air = x10 3 C H2 Ox exp ( t) Where t is the temperature in degrees Celsius ( C)

16 After calibration Instrument calibration label (F) Sealing the instrument- No tampering allowed (A-E) Calibration void if seals are broken A B D E F C

17 Role out of Dräger Alcotest 9510 Role out started in 2015 Implementation phase, 1 August 2016 in Western Cape SAB Sponsoring the EBA to priority areas Contributing back to the country by promoting safety on the road and in the work place

18 Positive remarks Drager instruments are being introduced back to South Africa Breathalysers provide reliable measurements Quick and reliable results in a few minutes Blood tests will still be done

19 Conclusion Breathalysers offer reliable and quick results in a few minutes Traceable to the SI unit mass- Ethanol CRMs Law enforcement and safety of personnel

20 THANK YOU