Pub Companies - Business, Innovation and Skills Committee Contents

Written evidence submitted by Paul Davies

1.  Along with my Partner, I am the leaseholders of The Cricketers Arms, Bedford, a Punch lease that was negotiated in 2005.

2.  I am a degree qualified electronic engineer with many years experience in the design and operation of measurement systems, I submitted to the last sitting of the committee my concerns of the use of the Brulines flow monitoring system by the pub companies and the potential for wrongful accusation of buying out of tie due to serious flaws in the system.

3.  The committees recommendation in the follow up report 4 March 2010 was

"that the Government, through the National Measurement Office, urgently clarifies the position of beer flow monitoring equipment in relation to the Weights and Measures Act 1985. Such equipment must be included under the Act for calibration and verification purposes."

This was modified in the Government's response to

"Government is clear that the industry should voluntarily ensure that all such measuring equipment is calibrated by the National Measurements Office. However should the industry fail to do so within a reasonable time frame this will result in Government prescribing the equipment to ensure fairness."

4.  In response to this, Brulines commissioned the National Measurement Office (NMO) to undertake tests on the i-draught and DMS versions of their flow monitoring equipment. These Brulines designed and commissioned tests were not the voluntary calibration the Government was requesting.

5.  The results of these tests were published by the NMO without any conclusions by the NMO. The results were analysed by Brulines and their own conclusions were published in their "Comprehensive Guide To Flow Monitoring". They concluded in their analysis that the equipment is fit for purpose. The NMO drew no such conclusions.

6.  Brulines use a very simple method of calculating the error for each test. They sum the errors giving equal weight to each point. In this method a large negative error will be canceled by an equally large positive error giving a false impression of accuracy.

7.  To give an example of this, the NMO Test 3, Brulines give the error for this test as -0.71% for both the i-draught and DMS systems. As can be seen from the graph of the percentage error the DMS system saw huge positive and negative errors.

The fact that these cancel each other may be coincidental, further testing should be done to confirm that a large negative is always cancelled out with a large positive as Brulines suggest is the case.

8.  In response to Brulines' Comprehensive Guide to Flow Monitoring I undertook a more scientific analysis of the NMO results and Brulines Comprehensive Guide To Flow Monitoring and concluded that both the i-draught and DMS systems are not stable or repeatable enough to conclude that they are fit for purpose.[23]

9.  The systems do not cope well with every day dispense occurrences, such as barrels running out and entrained gas. Heavy reliance is placed by Brulines on their "robust auditing" to rectify the failings of the systems. To date there is nothing to support that this robust auditing process will recognise and correct the problems encountered in the NMO testing or use in the field.

10.  I include my more detailed documents analysing the NMO test results and Brulines Comprehensive Guide To Flow Monitoring. I also include my explanation of the calibration "k" factor which is so important in the operation of such systems.[24]

11.  I apologise for the length of these documents, but they are considerably shorter than the NMO report and Brulines Comprehensive Guide To Flow Monitoring.

19 June 2011

23   Ev not printed Back

24   Ev not printed Back

previous page contents next page

© Parliamentary copyright 2011
Prepared 6 October 2011