PIR with tamper

["Yongil" <disid386@xxxxxxxxxxx>]

Our a customer got a big burglary accident some days ago.
The burglar cheated the customer pretending maintenance,
then put paper tissues into all PIR's inside in the day time.
So all PIR could not dectect any thieves at night.

The customer didn't verify whether the maintenance person was
a real our company's employee.
I think that's a customer's critical fault.
The customer, however, cannot understand
why the sensor within tissues inside cannot detect the fact.

Any comments would be appreciated.

Yongil