Setting "Uses Special Equipment" for a Service will block same service from being chosen again within any previously scheduled time period. In short the same service cannot overlap itself.
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The patient can still schedule a different service which overlaps a service with "Uses Special Equipment" checked.
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Click the All Tabs (Looks like a plus + sign)

Click the Services tab

Click the View "All" Go button to see all Services

Click on a Service

Click Edit

Check "Uses Special Equipment"

Click Save
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