Rotameter (flow meter)


Rotameters are devices that enable flow to be measured using a float that sits on a stream of gas within a glass tube and rises proportional to gas flow.


  • controlled delivery of medical gases at appropriate flow rates


  • glass tube containing a float which is elevated by a stream of moving gas
  • outlet for attachment of tubing
  • inlet from pressure regulator device attached to gas source
  • control knob


  • the float is raised in the tube as gas flow increases
  • cylinder markings allow determination of flow rate
  •  reading is taken at the centre of the float
  • glass cylinder must be upright
  • float should spin (shows that it is not stuck)


  • Incorrect function if not held vertically
  • float can stick if excess static electricity/debris
  • breakage of glass cylinder
  • malfunction of valve controlling flow


  • Different meters are required for different gases as flow rates depend on  gas properties such as viscosity and density
  • Different flow meters are used for different purposes (e.g. paediatric 0–5 L/min; and adult 0–15 L/min)

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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