How much FiO2 does a true Non Rebreather Mask NRB, Simple Face Mask, and BVM delivers for Pre Ox?

Information for FiO2 % comes from manufacturers instructions and The Walls Manual of Emergency Airway Management 5th Edition ISBN-13: 978-1496351968 Flush Rate Oxygen for Emergency Airway Preoxygenation Was published in Ann Emerg Med, not JAMA. https://www.annemergmed.com/article/S...