# Create Safety Data Expression Building Blocks Learn how to create blocks of _Case_ data evaluation expressions that you can reuse in multiple _Safety Reporting Rules_. ## About Safety Data Expression Building Blocks {#about} With _Safety Data Expression Building Blocks_, you can create _Case_ data evaluation expressions that you can combine and reuse in any number of _Safety Rules_ with the _Safety Data Expression Building Blocks_ reporting rule parameter. This provides an efficient way to create _Safety Rules_ that share similar _Case_ data evaluation requirements and reduces the administrative effort required to maintain large groups of _Safety Rules_. ## Create Safety Data Expression Building Blocks {#create} To create a _Safety Data Expression Building Block_: 1. Navigate to **Business Admin > Objects > Safety Data Expression Building Blocks**. 2. Select **Create**. 3. Complete the applicable [fields][3]. 4. Select **Save**. ### Safety Data Expression Building Block Fields {#fields} The following fields may be available:

Field Description

Name Enter a unique name for the Safety Data Expression Building Block.

Field	Description
Name	Enter a unique name for the Safety Data Expression Building Block.
Building Block Expression	Enter a Case data evaluation expression. The expression must be a `VS_LET` function with one of the following objects as the start of the `path_to_validating_records`: For global Case evaluation: `case_version__v` `eligible_case_assessments__v` For Localized Case evaluation: `case_version__v` `eligible_case_assessments__v` `localized_case_version__v` `eligible_localized_case_assessments__v` Vault evaluates the expression whenever the Rule Engine runs a Safety Rule Set on a Case that contains a Safety Data Expression Building Blocks rule parameter that references this Safety Data Expression Building Block. For help with writing Case data evaluation expressions, see Configure Custom Validation Criteria and Create Formula Expressions.
API Name	Enter a unique `__c` API name for this Safety Data Expression Building Block. When creating a Safety Rule Parameter of the type Safety Data Expression Building Blocks that uses this building block, enter this API Name in the Value field of the rule parameter.

Building Block Expression

Enter a Case data evaluation expression. The expression must be a VS_LET function with one of the following objects as the start of the path_to_validating_records:

For global Case evaluation:
- case_version__v
- eligible_case_assessments__v
For Localized Case evaluation:
- case_version__v
- eligible_case_assessments__v
- localized_case_version__v
- eligible_localized_case_assessments__v

Vault evaluates the expression whenever the Rule Engine runs a Safety Rule Set on a Case that contains a Safety Data Expression Building Blocks rule parameter that references this Safety Data Expression Building Block.

For help with writing Case data evaluation expressions, see Configure Custom Validation Criteria and Create Formula Expressions.

API Name

Enter a unique __c API name for this Safety Data Expression Building Block.

When creating a Safety Rule Parameter of the type Safety Data Expression Building Blocks that uses this building block, enter this API Name in the Value field of the rule parameter.

[1]: #about [2]: #create [3]: #fields