Hummingbird Presents Revolutionary Micro Paramagnetic Technology

February 10, 2014

Crowborough, UK, 10– Hummingbird Sensing Technology presents a Paper on Hummingbird’s RoHs compliant paramagnetic oxygen sensors, which are set to revolutionize the measurement of oxygen in anesthesia and respiratory care.

Dominic Corsale, General Manger at Hummingbird Sensing Technology explains: “It is well established that accurate measuring oxygen in anesthesia and ventilation is extremely important and until now, electrochemical sensors have been favored for their power and size. However, they do have drawbacks, in particular lifecycle and the associated replacement cost. Hummingbird has developed a very versatile RoHs compliant paramagnetic alternative, which matches its rival in size and compatibility whilst dramatically reducing the cost and power consumption with unrivalled longevity. RoHs compliancy is especially significant, given the estimated 1.2m electrochemical cells sold each year in medical devices world-wide. These devices will have to become RoHs compliant in Europe, starting in July 2014 and US January 2015.

Written by James Hobby, Chief Technical Author at Servomex Group, Hummingbird’s Paper put forward the case for the new Hummingbird miniature paramagnetic sensors, clearly defining the differences between the electrochemical and paramagnetic technologies and the overriding benefits of the latter.

It described electrochemical oxygen cells as having a particular weakness since they operate through a process similar to that found in batteries, where oxidation of the anode by the very oxygen they measure leads to a liberation of electrons. Eventually the entire active surface of the anode oxidizes and the sensors cease to work – the key weakness being the unpredictability of the point at which this will occur. The critical risk is a potential loss of oxygen measurement during an operation and affect this could have on patient outcome.

Traditionally this weakness has been offset by a costly, inefficient and environmentally unfriendly system: although manufacturers give the shelf life of an electrochemical cell as typically two years, in order to overcome the unpredictability and risk, Respiratory Technicians have been encouraged by producers of anesthesia ventilators to change the electrochemical sensors up to every six months.

By stark contrast, Hummingbird’s Paracube range presents an alternate technology for oxygen measurement with an indefinite lifetime. The positive effects are far reaching: clinicians and technicians working with ventilators will no longer need to replace the sensors and the risk to patients through cell failure is removed. Hospital management will see cost efficiency through a substantial return on investment (ROI) over the product lifetime, whilst environmentally the need for the continuous disposal of short-lived electrochemical cells is negated.

So how do Hummingbird’s sensors work? Corsale explains: “While paramagnetic based sensors has been used for patient monitoring since the 1970’s, their use for delivered oxygen measurement (FiO2) has until recently been limited by a combination of size, power consumption, interface compatibility and cost. Hummingbird’s sensors exploit the property of oxygen to be strongly attracted to a magnetic field – paramagnetism – using the torsion dumbbell system. The positioning of the dumbbell in a strong magnetic field gradient produces a force that varies proportionally with the oxygen concentration present. Since no consumption occurs with this approach, each device has an indefinite lifetime. “

He continues: “Improvement in electronics and sensor technology over the last decade have dramatically reduced the size, cost and power consumption, permitting wider use with the associated opportunities for improvements in FiO2 monitoring and therapy. The revolutionary development of Hummingbird’s miniature Paracube Micro sensors has lifted the traditional limitations of paramagnetic sensing, providing the medical world with a very viable alternative for the first time in four decades.”

Dr. Michael Jopling Anesthesia Medical Director at Mt. Carmel St Ann Hospital Columbus Ohio and Past President of STA, said: “I am happy to see cost effective alternative to electro chemical cells and encourage manufactures to start incorporating RoHS compliant technology into new anesthesia and critical care ventilators.”

The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS) Regulations implement the RoHS Directive which bans the placing on the EU market of new electrical and electronic equipment containing more than the agreed levels of lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyl (PBB) and polybrominated diphenyl ether (PBDE) flame retardants.

For more details, visit

Add Comment


Sensors 2017 Call for Speakers



Twitter Feed

Find It Fix It Forum

Sensors invites you to join the Findit-Fixit Forum, where you can get answers to your sensing questions—concerning technologies, products, methods, applications, and services--and also offer help to your fellow engineers. The Forum covers all kinds of topics, from the basics to the extraordinary.

Join the discussion!

© Copyright 2016 Questex, LLC. All Rights Reserved. Sensorsmag. Privacy Policy | Terms of Use

If you are having technical difficulties or considerations, please contact the webmaster.