Looking at the health monitor for HADR health indicators:
One of them being:
Indicator Name = db.hadr_delay
Default = Yes
Type = Threshold-based
Warning = 10
Alarm = 15
Unit = Minutes
Sensitivity = 0
Formula = (db.hadr_log_gap*var.refresh_rate/60)DIV(delta(db.hadr_secondary_log_pos));
Actions = Disabled
Threshold or State checking = Enabled

Was wondering where db2 gets the values for the variables in the formula used to calculate db.hadr_delay.

Thank you in advance.

Database snapshot has the log postion on the primary and standby database at any given time. The snapshot also provides an average log gap number.

I assume the refresh rate has something to do with how often the health monitor is checking these numbers.

You can probably get the same numbers with db2pd command using the HADR option (but I will let you check that one out).