FDA
Model 509M Pulse Oximetry Interface Module
Software versions 2.0 or 2.5
Audio alarm may fail to sound when SpO2 limits drop below the set limits
Respironics notified customers by letter dated 9/3/02 of the problem with the failure of the audible alarm. A correction would require replacement of the speaker. Non-responders were recontacted by second letter on 2/24/2004.