APPROACHES IN THE AREA OF MEASUREMENT UNCERTAINTIES

1. APPROACHES IN THE AREA OF MEASUREMENT UNCERTAINTIES Grant Symons Australian Communications Industry Forum

2. APPROACHES TO MEASUREMENT UNCERTAINTIES • Background • Options • Best practice • Setting the acceptable measurement uncertainty • Risk management

3. BACKGROUND • Impact of measurement uncertainties on product acceptance • Treatment of measurement uncertainties is addressed in each individual standard at development • Uncertainties are a range: • Normally confidence level of 95%

4. OPTIONS Measurementuncertainty Measured result

5. OPTION 1Self Declaration

6. OPTION 2Use recorded result

7. OPTION 3Use recorded result and uncertainty

8. BEST PRACTICE • Not Option 1 – permits use of unaccredited testing • Option 2 dilutes standards • “Shared risk” • Option 3 encourages accurate test practices • Uncertainty policy should not penalise supplier in the event of any post market testing

9. MEASURMENT UNCERTAINTY LIMITS • Setting maximum uncertainty limits does not necessarily encourage best practice • Difficult to know what limits “should” be • No incentive to improve test methods • Option 3 allows performance to be part of a commercial relationship

10. RISK MANAGEMENT • No single option appropriate for all cases • Low risk standards – option 1 • Example: Low power RF transmitters • Medium risk standards – option 2 • Example: EMC limits • High risk standards – option 3 • Example: Safety of life, Radiocommunications products

11. CONCLUSION • Sliding scale of measurement uncertainty application • Pick the option appropriate for the products risk category • The aim is to minimise impediments to the application of standards in world wide markets