We do two checks; one based on standard deviation and one acceleration check.
We start by calculating the standard deviation of the time series of the AST. Then we reject the samples that are outside 8 times standard deviation. We repeat this process after removing the out-layers at the same time as we reduce the n-times standard deviation criteria. We repeat until we've reach 4 times standard deviation.
The acceleration check is checking if the change of wave height is physically possible taking gravity into consideration.
And what happens with the data gaps, you may ask. The gaps created by the removed outliers are linearly interpolated with each iteration of identifying the outliers.