Is it possible to prevent a record and it's fields from being deleted, without admin level intervention??
The short answer is yes.
You will need to become familiar with privelege sets. A good place to start is the following for FMP14 (other versions are available for previous versions if you are not using 14):
The FileMaker Security Guide | FileMaker
Not only will you have to understand security you should understand how to apply custom menus that restrict access to "command" functions like manage database and manage layouts if you want to prevent users from removing fields from layouts and tables.
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