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PubMed · 7293704

Portable emergency ventilators. Sensitivity to environment.

B E Dahlgren·O Engdahl·H Nilsson
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Abstract

The function in various types of climate of three ventilators which are commercially available in Sweden: Motivus, Pneupac 2 and Logic 07, was tested as well as their sensitivity to vibration. The ventilators functioned in subzero temperatures only if the driving gas had a low humidity content. They also required an increased driving gas pressure. Only Logic 07 would function below -20 degrees C. In a hot climate there were no functional disturbances. Motivus and Pneupac 2 had few resonance frequencies during the vibration tests. Logic 07 had a very marked resonance frequency at 60 Hz, as well as in other ranges, which disturbed the ventilatory function since the vibration affected the ventilatory frequency regulator. All three ventilators functioned without any complaints after being subjected to vibration tests for at least 15 min at the observed resonance frequencies, or to shock tests. The results suggest that a through scrutiny should be carried out of the function of compact ventilators in various environments.

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BibTeXRIS

B E Dahlgren, O Engdahl, H Nilsson. 1981. Portable emergency ventilators. Sensitivity to environment.. https://doi.org/10.1111/j.1399-6576.1981.tb01604.x

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