Effective Airflow Visualization Studies. Gordon Farquharson, July 2017

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1 Effective Airflow Visualization Studies Gordon Farquharson, July 2017 Slide 1 PharmOut 2017

2 Agenda Regulatory imperative Role of CFD Air velocity measurements Airflow visualisation to prove effectiveness of airflow Slide 2 PharmOut 2017

3 Regulatory Imperative Slide 3 PharmOut 2017

4 UDAF Guidance US FDA. Industry uses this US guidance as a reference (2004 Aseptic guidance. US FDA s guidance really says it all. If you re unfamiliar I suggest you read it carefully. Proper design and control prevents turbulence and stagnant air in the critical area. Once relevant parameters are established, it is crucial that airflow patterns be evaluated for turbulence or eddy currents that can act as a channel or reservoir for air contaminants (e.g., from an adjoining lower classified area). In situ air pattern analysis should be conducted at the critical area to demonstrate unidirectional airflow and sweeping action over and away from the product under dynamic conditions. The studies should be well documented with written conclusions, and include evaluation of the impact of aseptic manipulations (e.g., interventions) and equipment design. Videotape or other recording mechanisms have been found to be useful aides in assessing airflow initially as well as facilitating evaluation of subsequent equipment configuration changes. It is important to note that even successfully qualified systems can be compromised by poor operational, maintenance, or personnel practices. Slide 4 PharmOut 2017

UDAF Guidance Annex 1 EU & PIC/S GMP EU and PIC/S Guidance is very limited by comparison, and is quite out of date in relation to normal practice Recent EU

5 UDAF Guidance Annex 1 EU & PIC/S GMP EU and PIC/S Guidance is very limited by comparison, and is quite out of date in relation to normal practice Recent EU inspections exhibit reported Critical & Major Observations on inadequate airflow visualisation of Grade A UDAF zone for aseptic processes. Slide 5 PharmOut 2017

6 Air flow visualisation tests Only applicable in UDAF systems Slide 6 PharmOut 2017

7 The linked problems Measuring velocity & proving effectiveness Unidirectional Airflow Side return Velocity at working height Slide 7 PharmOut 2017 Turbulent Vortex risk area

8 Slide 8 PharmOut 2017

9 CFD for UDAF Systems Slide 9 PharmOut 2017

10 Authors opinion/experience with CFD CFD - Computation Fluid Dynamics. Good design tool for applications that are too complex or unusual to rely on prior experience. Computer software and modelling not easy to use need specialist skill and experience to develop a representative model. Not a cheap process of evaluation, but can be good value in context with the risk of getting it wrong. My experience: Unusual UDAF in aseptic processing. Critical environmental control in animal husbandry. Safety applications for handling hazardous biological and chemical materials. Building discharges an alternative to wind-tunnel tests. Slide 10 PharmOut 2017

The Facility Requirements A Japanese Pharmaceutical Company was seeking to optimise the design of a cleanroom containing vial filling machines, lyophiliser loading and automated transport

11 The Facility Requirements A Japanese Pharmaceutical Company was seeking to optimise the design of a cleanroom containing vial filling machines, lyophiliser loading and automated transport systems. The GMP requirements were based primarily on the US FDA 2004 APG recommendations for achieving effective clean air protection of a critical aseptic process. Slide 11 PharmOut 2017

12 3D Illustration of the Lyophiliser problem Non- UDF Grade B UDF Grade A Top of Lyo door Grade A AGV adjacent to Pizza opening Slide 12 PharmOut 2017

13 CFD Grid Illustration The physics of fluid flow, heat transfer and associated processes are contained in the Navier-Stokes equation. Airflow modelling iteratively solves a simultaneous set of N-S equations for spatial volume divided up into a number of finite cells. The model can be solved for the airflow itself, and sources of heat and other contaminants. Slide 13 PharmOut 2017

14 Vector Illustration Slide 14 PharmOut 2017

15 Slide 15 PharmOut 2017

16 Slide 16 PharmOut % Ceiling coverage

17 100% Ceiling coverage 50% Ceiling coverage Slide 17 PharmOut 2017

18 The Study Output = Results & Records Enabled reduction of the area of the uni-directional flow Grade A cleanzone by 50%. This in turn enabled the total air volume required to ensure the correct cleanroom cleanliness classes to be reduced by approximately 40% with the consequent significant saving of installed plant and energy consumption. Selection of the correct type of diffuser in the non-unidirectional flow zone to ensure that the critical airflow is not disrupted. Resolution of the basic dimensions required inside the vial transport system to avoid airflow updraft and vortex generation during vial transfer to and from the lyophiliser. Allowed testing of the effect of temperature of supply air on the airflow. Negative buoyancy can have a huge effect on UDAF effectiveness. Provided a clear guide as to where to focus testing effort during HVAC system commissioning and flow visualization. Slide 18 PharmOut 2017

19 Airflow visualisation studies Critical Systems Ltd 2016 November 2016 Slide 19 PharmOut 2017

20 Airflow Visualization Studies Guidelines 1. Have written objectives for each visualization study. 2. Even if studies are conducted during a shutdown, try to operate in a production mode with personnel in full garb observing good aseptic technique during a simulation. 3. Begin video taping the study by showing the equipment below the ceiling level that is being washed by airflow and then pan up to show the smoke at the ceiling. 4. Use a smoke source that is adequate to show good airflow. 5. Do not get too close to equipment with the smoke source. This can cause smoke to display a turbulent action as it strikes flat surfaces. 6. Record all data at the time smoke studies are conducted. (time, date, personnel present, room location, etc.) 7. Have clear acceptance criteria, and report against these. Slide 20 PharmOut 2017

Airflow Visualisation Studies - Guidance Isothermal aerosol (smoke). Water vapour or propylene glycol (glycerol). Should include operations and interventions. Choreograph the visualisation.

21 Airflow Visualisation Studies - Guidance Isothermal aerosol (smoke). Water vapour or propylene glycol (glycerol). Should include operations and interventions. Choreograph the visualisation. May need aids to improve optical contrast. Pulsed aerosol source can help visualise velocity. Multiple nozzles helps visualise parallelism of flow. Frequency At system qualification and after significant system or process change. Slide 21 PharmOut 2017

22 Slide 22 PharmOut 2017

23 Example poor airflow in an isolator Slide 23 PharmOut 2017

24 Example improved airflow in Isolator experiment Slide 24 PharmOut 2017

25 Thank you for your time. Questions? Gordon Farquharson Executive Consultant Slide 25 PharmOut 2017

26 PharmOut Copyright Notice All rights reserved This presentation and all associated materials are copyrighted and all rights reserved by PharmOut. No part of this presentation may be reproduced or transmitted in any form or for any purpose without the express permission of PharmOut in writing. The information contained herein may be changed without prior notice. Data contained in this presentation serves informational purposes only. PharmOut does not warrant the accuracy or completeness of the information, text, graphics, links, or other items contained within this presentation. This presentation is provided without a warranty of any kind, either express or implied, including but not limited to the implied warranties of merchantability, fitness for a particular purpose, or non-infringement. PharmOut shall have no liability for damages of any kind including without limitation direct, special, indirect, or consequential damages that may result from the use of this presentation. Slide 26 PharmOut 2017

Uni-directional Airflow Systems Working Height Velocity (WHV) Gordon Farquharson July 2017

Uni-directional Airflow Systems Working Height Velocity (WHV) Gordon Farquharson July 2017 Agenda: Uni-directional Airflow Systems Regulatory requirements & expectations. Measurement methods. Location