# Enable Configurable PII and E2B Masking for NullFlavor Fields

Learn how to configure your Vault's field masking for fields configured with _Reasons Omitted_.

## About the Feature

With the 24R3 release, Vault Safety introduces configurable nullFlavor field masking. This feature extends functionality on <a href="/en/gr/01422/">existing fields with configurable masking</a>. Previously, during E2B generation, Vault Safety always masked fields with nullFlavors. When configured, users can now exclude nullFlavors from patient content protection when generating masked reports, so Vault populates the nullFlavor values.

To align with your business rules, you can configure whether _Null Flavors_ is an available option in the _Exception to Patient Content Protection_ field for users generating masked reports. After you have configured this feature, for more information on exceptions to patient content protection, see <a href="/en/gr/01225/#exceptions-to-patient-content-protection">Generate Masked Safety Reports</a>.

## Prerequisite

Before configuring this feature in your Vault, you must enable <a href="/en/gr/01391/">Masked Content Distributions</a>.

## Configure Exceptions to Patient Content Protection

To configure nullFlavor masking, manage the _Exceptions to Patient Content Protection_ picklist <a href="/en/gr/53941/#editing-picklist-dependencies">field's dependencies</a> for the following objects:

* _Reporting Family_
* _Transmission_
* _Transmission Output Template_