When receiving a red notification, the very first thing you should do is check on your baby. If it was not an emergency, it was probably caused by one of the following...
Poor Sock Fit
Sock fit/placement issues are the most common cause of false notifications.
Even in the hospital, the #1 cause of incorrect readings is poor sensor placement.
Review the following article for help on finding the best fit and placement:
Sock Too Loose
The most common issue is that the sock is close enough to get a reading, but still too loose, causing faint readings.
Check to make sure the sensor windows are flat against your baby's skin.
Review the following articles for help on sock fit:
Check for signs of sickness. Red notifications can be more frequent when baby is sick or congested.
Try using a nasal aspirator to clean out baby's nose.
If sickness persists it may be a good idea to call your pediatrician.
When to call your pediatrician (American Academy of Pediatrics)
Any movement picked up by the Smart Sock is assumed to be your baby's movement.
Sometimes, a swing, vibrating mat, or even patting your baby's back can be mistaken for their heart rate and set off the notification. This is also not common.
Elevation can affect oxygen level. In higher elevation areas (like areas in Colorado), baby's oxygen levels can sit lower than average.
Elevation doesn't necessarily cause red notifications but can make them more frequent.
Foot Too Cold
This is not common but cold feet can cause red notifications. This is because there is less blood flow in the foot for the pulse oximeter to pick up.
There are other possibilities that could lead to a red notification.
Make sure to always observe safe sleeping practices.