Research & Development World

  • R&D World Home
  • Topics
    • Aerospace
    • Automotive
    • Biotech
    • Careers
    • Chemistry
    • Environment
    • Energy
    • Life Science
    • Material Science
    • R&D Management
    • Physics
  • Technology
    • 3D Printing
    • A.I./Robotics
    • Software
    • Battery Technology
    • Controlled Environments
      • Cleanrooms
      • Graphene
      • Lasers
      • Regulations/Standards
      • Sensors
    • Imaging
    • Nanotechnology
    • Scientific Computing
      • Big Data
      • HPC/Supercomputing
      • Informatics
      • Security
    • Semiconductors
  • R&D Market Pulse
  • R&D 100
    • Call for Nominations: The 2025 R&D 100 Awards
    • R&D 100 Awards Event
    • R&D 100 Submissions
    • Winner Archive
    • Explore the 2024 R&D 100 award winners and finalists
  • Resources
    • Research Reports
    • Digital Issues
    • R&D Index
    • Subscribe
    • Video
    • Webinars
  • Global Funding Forecast
  • Top Labs
  • Advertise
  • SUBSCRIBE

Measuring Airflow in the Cleanroom

By R&D Editors | April 16, 2014

To confirm that the system is working properly, it is necessary to check the airflow at the supply vents and also to check the distribution of airflow throughout the room. Image: Kanomax Maintaining appropriate air velocity in the cleanroom helps ensure a clean environment; correct system performance plays an important role. To make certain the system functions as expected, periodic checks using the proper instruments are recommended to measure velocity and uniformity in the clean space.

Room performance can be affected by room size, AHU capacity, length of duct run, as well as other factors. Methods used to check airflow within a cleanroom vary depending on the ventilation set-up—the two most common being laminar flow and turbulent airflow.  

Ventilation set-up

In a laminar flow system, air flows through the cleanroom in one direction, either horizontal flow or top to bottom. Koji Miyasaka, with Kanomax, Andover, N.J., notes that, “To confirm that the system is working properly, it is necessary to check the airflow at the supply vents and also to check the distribution of airflow throughout the room. At the supply vents or fan filters the volumetric flow should be checked by using the following formula: Q = V x A. (V is the average or center air velocity and A is the area of the vent or fan filter.) To determine the total volumetric flow for the room, the procedure should be repeated at each vent or fan filter and then summed. This number should then be compared to the specifications for the cleanroom to find if it is in tolerance. Many modern anemometers come with this calculation function built in.”

In a turbulent airflow system, the room is designed to dilute and remove contaminates based on a certain number of air exchange rates per hour. To check this type of system, measure the airflow at both the supply and the returns and then calculate the number of air exchanges that occur per hour.”

Taking measure

“In unidirectional cleanrooms the airflow velocities are typically measured using either a thermal anemometer (mass flow devices) or an electronic micromanometer in conjunction with a multi-point sensor array (volumetric flow device),” says Cary Binder, ENV Services Inc., Hatfield, Pa. Binder points to guidance from IEST-RP-CC 006.3 Section 6.1.1b.1 which states, “Divide the plane into a grid of equal area. Individual areas should not exceed approximately 0.4m2 (4 ft2)” while the probe is typically placed 6-in. from the filter face or diffuser. 

Binder offers the following steps for measurement. “Calculate the effective media area of each filter and multiply the average velocity for each filter to determine the airflow volume (cfm). Add the calculated volumes for all the filters and the result is the total airflow volume for the room. Divide the total airflow volume for the room by the room volume and multiply by 60 to obtain the ACPH for the room.  When a balometer is used, simply add the measured volumes for all the filters and the result is the total airflow volume for the room.”

For more information

The contributors to this article have provided more detailed explanation and examples in articles that are hosted on the Controlled Environments website, www.cemag.us. On the site, search “air velocity” to find expanded material on the topic of airflow measurement for cleanrooms and compounding pharmacies.


Patrice Galvin and MaryBeth DiDonna are Editorial Director and Managing Editor, respectively, of Controlled Environments.

This article appeared in the April 2014 issue of Controlled Environments.

Related Articles Read More >

6 essentials for seismic rated cleanrooms
Critical Spaces Control Platform
Phoenix Critical Spaces Control Platform uses automation to direct airflow
Endiatx
Endiatx aims to boldly go beyond traditional endoscopy and, eventually, redefine surgical scale
FMN Laboratory researcher in a cleanroom
Take our quiz to test your cleanroom IQ, covering everything from ISO Classes to ULPA filtration
rd newsletter
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, trends, and strategies in Research & Development.
RD 25 Power Index

R&D World Digital Issues

Fall 2024 issue

Browse the most current issue of R&D World and back issues in an easy to use high quality format. Clip, share and download with the leading R&D magazine today.

Research & Development World
  • Subscribe to R&D World Magazine
  • Enews Sign Up
  • Contact Us
  • About Us
  • Drug Discovery & Development
  • Pharmaceutical Processing
  • Global Funding Forecast

Copyright © 2025 WTWH Media LLC. All Rights Reserved. The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media
Privacy Policy | Advertising | About Us

Search R&D World

  • R&D World Home
  • Topics
    • Aerospace
    • Automotive
    • Biotech
    • Careers
    • Chemistry
    • Environment
    • Energy
    • Life Science
    • Material Science
    • R&D Management
    • Physics
  • Technology
    • 3D Printing
    • A.I./Robotics
    • Software
    • Battery Technology
    • Controlled Environments
      • Cleanrooms
      • Graphene
      • Lasers
      • Regulations/Standards
      • Sensors
    • Imaging
    • Nanotechnology
    • Scientific Computing
      • Big Data
      • HPC/Supercomputing
      • Informatics
      • Security
    • Semiconductors
  • R&D Market Pulse
  • R&D 100
    • Call for Nominations: The 2025 R&D 100 Awards
    • R&D 100 Awards Event
    • R&D 100 Submissions
    • Winner Archive
    • Explore the 2024 R&D 100 award winners and finalists
  • Resources
    • Research Reports
    • Digital Issues
    • R&D Index
    • Subscribe
    • Video
    • Webinars
  • Global Funding Forecast
  • Top Labs
  • Advertise
  • SUBSCRIBE