58
Concepts of Alarm Response Delay
As with any pulse oximeter equipment, the audible and visual alarms are subject to alarm response
delay, which is composed of Alarm Condition Delay and Alarm Signal Generation Delay. Alarm Condition
Delay is the time from the occurrence of the triggering event to when the alarm system determines the
alarm condition exists. While Alarm Signal Generation Delay is the time from the onset of an alarm
condition to the generation of its alarm signal. The graphic below is a simplified illustration of the concept
of alarm response delay and does not reflect actual lengths of delays.
Reference Definition Reference Definition
1 SaO
2
4 Alarm Signal Generation
2 Alarm Limit SpO
2
Saturation
3 Displayed SpO
2
t Time
The Alarm Condition Delay is graphically represented as t
2
– t
1
in the figure above to show the delay due
to processing and averaging.
The Alarm Signal Generation Delay is graphically represented as t
3
– t
2
in the figure above to show the
delay due to alarm system strategy and communication time.
The overall alarm system delay time is graphically represented as t
3
– t
1
.
For more information about alarm response delay, refer to ISO 80601-2-61.
To Next Page
Loading...