Abstract

LNE has set up a new national standard in gas flowrate measurement between 0.2 mg·s-1 and 200 mg·s-1 of nitrogen or dry air to calibrate automatically Molbloc laminar flowmeters. This paper describes the metrological qualification of this standard based on the dynamic gravimetric method: optimization of the method to reduce the uncertainty by a factor of 2 compared to those obtained with the LNE old gravimetric benches, participation to an interlaboratory comparison to validate this result. The uncertainty calculation is developed up to the calibration of a Molbloc laminar flowmeter.

Key words

dynamic gravimetric method
reference bench
uncertainty
comparison
calibration

Abstract

Until 2012, micro- and nano-flow rate measurements traceability was a problem, due to the lack of references at and below 1 mL·h-1. For drug delivery by infusion, uncertainty on real delivered flow rate can cause injuries or even death. Quality of volumetric dosing has to be closely controlled. Exact delivered volume and stability are critical parameters, particularly for drugs requiring low blood concentration for toxicity reasons, such as vasoactive and anesthetics. To meet this need, the national metrology laboratories LNE-CETIAT, DTI, IPQ, METAS and VSL have developed, in the scope of the European Research Project in Metrology “EMRP/HLT07 MeDD – Metrology for Drug Delivery”, calibration benches for flow rates from 600 mL·h-1 down to 600 nL·h-1. This article presents the work done at LNE-CETIAT in the scope of this project, including qualification of a calibration facility for flow rates from 1 mL·h-1 to 10 L·h-1, and temperature assessment of microflowmeters and drug delivery devices.

Key words

drug delivery devices
liquid micro-flow
gravimetric calibration
metrology for drug delivery

At micro and nano-scale liquid flow rates, calibration is critical, especially for applications such as volumetric dosing and drug delivery. In particular, for drugs with a very short half-life (in the order of one minute), or for drugs that require a very low blood concentration for toxicity reasons, such as vasoactive or anaesthetic drugs, the exact amount of volume administered as well as the stability of the flow rate are crucial.

Objectives

Establishment of an infrastructure for calibration of drug delivery systems for flows up to 10-100 nl/min

Development of transfer standards for on-site calibration of drug delivery equipment

Performance evaluation of drug delivery devices, dependence on operating conditions and clinical characteristics

Provision of a good practice guide for drug dispensing and improved calibration services for drug delivery devices

Summary

Find here the detailled description of the project:

http://www.drugmetrology.com

Publications and communications

BATISTA E., FILIPE E., BISSIG H., PETTER H.T., LUCAS P., OGHEARD F. and NIEMANN A.K., “European research project on microflow measurements – MEDD”, 9th International Symposium on Fluid Flow Measurement, Arlington, United States of America, April 14th-17th 2015.

BISSIG H., PETTER H.T., LUCAS P., BATISTA E., FILIPE E., ALMEIDA N., RIBEIRO L.F., GALA J., MARTINS R., SAVANIER B., OGHEARD F., NIEMANN A.K., LÖTTERS J. and SPARREBOOM W., “Primary standards for measuring flow rates from 100 nl/min to 1 ml/min – gravimetric principle”, Biomedical Engineering / Biomedizinische Technik, 60, 4, 2015, 301–316, DOI: 10.1515/bmt-2014-0145.

DAVID CH., MELVAD C., BISSIG H. and BATISTA E., “Research interlaboratories comparison for small liquid flow rates (2g/h to 600g/h)”, 16th Flow Measurement Conference (FLOMEKO), Paris, France, September 24th-26th 2013.

OGHEARD F., BATISTA E., BISSIG H., PETTER H.T., LUCAS P. and NIEMANN A.K., “Metrological assessment of micro flow-meters and drug delivery devices in the scope of the "MeDD" EMRP project”, 17e Congrès international de métrologie, Paris, France, September 21st-24th 2015, DOI: 10.1051/metrology/20150009004.

LUCAS P., SNIJDER R.A., TIMMERMAN A.M.D.E., BATISTA, E., BISSIG H. and OGHEARD F., “Best Practice Guide”, Version: 13-05-2015.

Partners

  • VSL,
  • CETIAT,
  • CMI,
  • DTI,
  • IPQ,
  • METAS,
  • TUBITAK,
  • FH Lubeck,
  • UMC Utrecht

The noise of machinery or equipment is a technical characteristic generally declared in terms of acoustic power (power level in dB in relation to a reference acoustic power of 10-12 watt). In Europe, this declaration of power is often imposed by regulation.

Objectives

Develop a primary reference source to disseminate the acoustic power unit

Summary

Find here the detailled description of the project

http://www.ptb.de/emrp/sib56-home.html

Publications and communications

CELLARD P., ANDERSSON H., BREZAS S., et WITTSTOCK V., “Automatic sound field sampling mechanisms to disseminate the unit watt in airborne sound”, Proceedings of the INTER-NOISE 2016, 45th International Congress and Exposition on Noise Control Engineering,  Towards a Quieter Future, Hamburg; Germany; 21 – 24 août 2016, 6762-6770

BREZAS S. , CELLARD P. , ANDERSSON H. , GUGLIELMONE C., KIRBAS C., “Dissemination of the unit Watt in airborne sound: aerodynamic reference sound sources as transfer standards”,In: Proceedings of the INTER-NOISE 2016, 45th International Congress and Exposition on Noise Control Engineering,  Towards a Quieter Future, Hamburg; Germany;  21 – 24 août 2016,  6762-6770

Partners

Laboratoires nationaux de métrologie :

  • PTB (DE),
  • INRIM (IT),
  • SP (SE),
  • TUBITAK (TK)