i don't know how to disable Volume Space thresholds
but you can try increase your volume size larger than your Lun Size
It makes your Volume still have "spare" size and Used Size always in under 100%.
When you attach your datastore to your VM / Esxi, you must leave the lil size. example: if you attach 5 TB datastore, you can only attach 4.9 TB. that means the size used is only 98% of your datastore. So you will avoid a warning or alert.
Are you looking to preven the Event from being logged by UM or from receiving a Notification from a configured Alert?
If you are looking to prevent UM from logging an Event, you can edit individual volume thresholds (Capacity: Space Nearly Full / Spacc Full / Days Until Full ). Navigate to an individual volume and click Actions > Edit Thresholds.
If you are looking to prevent Notifications from a triggered Alert, take a look at the Alert > Resources > Include | Exclude options If you have a specific naming convention for Volumes that are presented to ESX, you may choose Include all relevant Volumes in an Alert and then exclude specific Volumes via the Exclude tab using the "Name contains" string. Note that this will not prevent UM for logging an Event but it will prevent UM from notifying you per the Alert > Actions configuration.