You can pass the Session value as a function parameter. Put the script on the page and call the function in a expanded inline expression passing your Session variable as parameter (by concatenating the string) like this:
"<script>RefreshMaintainIncidents("+Session.IsHyperRefresh+");</script>"
Hope it helps.
"<script>RefreshMaintainIncidents("+Session.IsHyperRefresh+");</script>"
Hope it helps.