diff --git a/src/rad/resources/schemas/reference_files/distortion-1.0.0.yaml b/src/rad/resources/schemas/reference_files/distortion-1.0.0.yaml
index 24890cf2..60ceede9 100644
--- a/src/rad/resources/schemas/reference_files/distortion-1.0.0.yaml
+++ b/src/rad/resources/schemas/reference_files/distortion-1.0.0.yaml
@@ -7,6 +7,9 @@ title: Distortion Reference Schema
 
 datamodel_name: DistortionRefModel
 
+input_units: "pixel"
+output_units: "arcsec"
+
 type: object
 properties:
   meta:
diff --git a/src/rad/resources/schemas/reference_files/inverselinearity-1.0.0.yaml b/src/rad/resources/schemas/reference_files/inverselinearity-1.0.0.yaml
index a364deee..570746b6 100644
--- a/src/rad/resources/schemas/reference_files/inverselinearity-1.0.0.yaml
+++ b/src/rad/resources/schemas/reference_files/inverselinearity-1.0.0.yaml
@@ -7,6 +7,9 @@ title: Inverse Linearity Correction Reference Schema
 
 datamodel_name: InverselinearityRefModel
 
+input_units: "DN"
+output_units: "DN"
+
 type: object
 properties:
   meta:
diff --git a/src/rad/resources/schemas/reference_files/linearity-1.0.0.yaml b/src/rad/resources/schemas/reference_files/linearity-1.0.0.yaml
index c11ee5df..7b95f6b5 100644
--- a/src/rad/resources/schemas/reference_files/linearity-1.0.0.yaml
+++ b/src/rad/resources/schemas/reference_files/linearity-1.0.0.yaml
@@ -7,6 +7,9 @@ title: Linearity Correction Reference Schema
 
 datamodel_name: LinearityRefModel
 
+input_units: "DN"
+output_units: "DN"
+
 type: object
 properties:
   meta:
diff --git a/src/rad/resources/schemas/reference_files/refpix-1.0.0.yaml b/src/rad/resources/schemas/reference_files/refpix-1.0.0.yaml
index 1a5dc672..a63e328e 100644
--- a/src/rad/resources/schemas/reference_files/refpix-1.0.0.yaml
+++ b/src/rad/resources/schemas/reference_files/refpix-1.0.0.yaml
@@ -9,6 +9,9 @@ title: Reference Pixel Correction Reference Schema
 
 datamodel_name: RefpixRefModel
 
+input_units: "DN"
+output_units: "DN"
+
 type: object
 properties:
   meta: