diff --git a/launch_param_builder/utils.py b/launch_param_builder/utils.py
index b2a517e..f6afc0b 100644
--- a/launch_param_builder/utils.py
+++ b/launch_param_builder/utils.py
@@ -32,6 +32,7 @@
 from typing import List, Union
 import xacro
 from ament_index_python.packages import get_package_share_directory
+import math
 
 
 class ParameterBuilderFileNotFoundError(KeyError):
@@ -52,6 +53,20 @@ class ParameterBuilderFileNotFoundError(KeyError):
 ]
 
 
+def construct_angle_radians(loader, node):
+    """Utility function to construct radian values from YAML."""
+    value = loader.construct_scalar(node)
+    try:
+        return float(value)
+    except SyntaxError:
+        raise Exception(f"invalid expression: {value}")
+
+
+def construct_angle_degrees(loader, node):
+    """Utility function for converting degrees into radians from YAML."""
+    return math.radians(construct_angle_radians(loader, node))
+
+
 def raise_if_file_not_found(file_path: Path):
     if not file_path.exists():
         raise ParameterBuilderFileNotFoundError(f"File {file_path} doesn't exist")
@@ -62,17 +77,23 @@ def load_file(file_path: Path):
     try:
         with open(file_path, "r") as file:
             return file.read()
-    except EnvironmentError:  # parent of IOError, OSError *and* WindowsError where available
+    except OSError:  # parent of IOError, OSError *and* WindowsError where available
         return None
 
 
 def load_yaml(file_path: Path):
     raise_if_file_not_found(file_path)
 
+    try:
+        yaml.SafeLoader.add_constructor("!radians", construct_angle_radians)
+        yaml.SafeLoader.add_constructor("!degrees", construct_angle_degrees)
+    except Exception:
+        raise Exception("yaml support not available; install python-yaml")
+
     try:
         with open(file_path, "r") as file:
-            return yaml.load(file, Loader=yaml.FullLoader)
-    except EnvironmentError:  # parent of IOError, OSError *and* WindowsError where available
+            return yaml.safe_load(file)
+    except OSError:  # parent of IOError, OSError *and* WindowsError where available
         return None