diff --git a/src/rl_ai2thor/envs/actions.py b/src/rl_ai2thor/envs/actions.py
index da31eeb..63f812a 100644
--- a/src/rl_ai2thor/envs/actions.py
+++ b/src/rl_ai2thor/envs/actions.py
@@ -26,11 +26,11 @@
 from enum import StrEnum
 from typing import TYPE_CHECKING, Any
 
+from rl_ai2thor.envs.tasks import ObjFixedPropId, ObjVariablePropId
 from rl_ai2thor.utils.general_utils import nested_dict_get
 
 if TYPE_CHECKING:
     from rl_ai2thor.envs.ai2thor_envs import ITHOREnv
-    from rl_ai2thor.envs.tasks import ObjFixedPropId
     from rl_ai2thor.utils.ai2thor_types import EventLike
 
 
@@ -135,6 +135,7 @@ class ActionCategory(StrEnum):
 
 # === Action Classes ===
 # TODO: Change perform to not need the environment
+# TODO: Add target value to object required property
 @dataclass
 class EnvironmentAction:
     """
@@ -368,7 +369,11 @@ def __call__(self, env: ITHOREnv) -> bool:
             bool: Whether the agent has visible running water in its field of view.
         """
         for obj in env.last_event.metadata["objects"]:
-            if obj["visible"] and obj["isToggled"] and obj["objectType"] in {"Faucet", "ShowerHead"}:
+            if (
+                obj[ObjVariablePropId.VISIBLE]
+                and obj[ObjVariablePropId.IS_TOGGLED]
+                and obj[ObjFixedPropId.OBJECT_TYPE] in {"Faucet", "ShowerHead"}
+            ):
                 return True
         return False
 
@@ -403,7 +408,7 @@ def __call__(self, env: ITHOREnv) -> bool:
         """
         return (
             len(env.last_event.metadata["inventoryObjects"]) > 0
-            and env.last_event.metadata["inventoryObjects"][0]["objectType"] == self.object_type
+            and env.last_event.metadata["inventoryObjects"][0][ObjFixedPropId.OBJECT_TYPE] == self.object_type
         )
 
     def _base_error_message(self, action: EnvironmentAction) -> str:
@@ -770,8 +775,7 @@ def __init__(self, ai2thor_action: str) -> None:
     clean_object_action,
 ]
 
-ACTION_CATEGORIES = {action.action_category for action in ALL_ACTIONS}
-ACTIONS_BY_CATEGORY = {category: [] for category in ACTION_CATEGORIES}
+ACTIONS_BY_CATEGORY = {category: [] for category in ActionCategory}
 for action in ALL_ACTIONS:
     category = action.action_category
     ACTIONS_BY_CATEGORY[category].append(action)
diff --git a/src/rl_ai2thor/envs/ai2thor_envs.py b/src/rl_ai2thor/envs/ai2thor_envs.py
index 6c92c71..01760c6 100644
--- a/src/rl_ai2thor/envs/ai2thor_envs.py
+++ b/src/rl_ai2thor/envs/ai2thor_envs.py
@@ -15,14 +15,15 @@
 from numpy.typing import ArrayLike
 
 from rl_ai2thor.envs.actions import (
-    ACTION_CATEGORIES,
     ACTIONS_BY_CATEGORY,
     ACTIONS_BY_NAME,
     ALL_ACTIONS,
+    ActionCategory,
+    EnvActionName,
     EnvironmentAction,
 )
 from rl_ai2thor.envs.reward import GraphTaskRewardHandler
-from rl_ai2thor.envs.tasks import GraphTask, PlaceObject
+from rl_ai2thor.envs.tasks import GraphTask, PlaceObject, ObjFixedPropId
 from rl_ai2thor.utils.ai2thor_types import EventLike
 from rl_ai2thor.utils.general_utils import ROOT_DIR, update_nested_dict
 
@@ -79,7 +80,7 @@ def _create_action_space(self) -> None:
 
         # Get the available actions from the environment mode config
         for action_category in self.config["action_categories"]:
-            if action_category in ACTION_CATEGORIES:
+            if action_category in ActionCategory:
                 if self.config["action_categories"][action_category]:
                     # Enable all actions in the category
                     for action in ACTIONS_BY_CATEGORY[action_category]:
@@ -90,20 +91,20 @@ def _create_action_space(self) -> None:
         # Handle specific cases
         # Simple movement actions
         if self.config["simple_movement_actions"]:
-            self.action_availablities["MoveBack"] = False
-            self.action_availablities["MoveLeft"] = False
-            self.action_availablities["MoveRight"] = False
+            self.action_availablities[EnvActionName.MOVE_BACK] = False
+            self.action_availablities[EnvActionName.MOVE_LEFT] = False
+            self.action_availablities[EnvActionName.MOVE_RIGHT] = False
         # Done actions
         if self.config["use_done_action"]:
-            self.action_availablities["Done"] = True
+            self.action_availablities[EnvActionName.DONE] = True
         # Partial openness
         if (
             self.config["partial_openness"]
             and self.config["action_categories"]["open_close_actions"]
             and not self.config["discrete_actions"]
         ):
-            self.action_availablities["OpenObject"] = False
-            self.action_availablities["CloseObject"] = False
+            self.action_availablities[EnvActionName.OPEN_OBJECT] = False
+            self.action_availablities[EnvActionName.CLOSE_OBJECT] = False
 
         available_actions = [action_name for action_name, available in self.action_availablities.items() if available]
         self.action_idx_to_name = dict(enumerate(available_actions))
@@ -290,8 +291,12 @@ def _sample_task(self, event: EventLike) -> GraphTask:
         """
         # Temporarily return only a PlaceObject task
         # Sample a receptacle and an object to place
-        scene_pickupable_objects = [obj["objectType"] for obj in event.metadata["objects"] if obj["pickupable"]]
-        scene_receptacles = [obj["objectType"] for obj in event.metadata["objects"] if obj["receptacle"]]
+        scene_pickupable_objects = [
+            obj[ObjFixedPropId.OBJECT_TYPE] for obj in event.metadata["objects"] if obj[ObjFixedPropId.PICKUPABLE]
+        ]
+        scene_receptacles = [
+            obj[ObjFixedPropId.OBJECT_TYPE] for obj in event.metadata["objects"] if obj[ObjFixedPropId.RECEPTACLE]
+        ]
 
         np_rng: np.random.Generator = self._np_random  # type: ignore
         object_to_place = np_rng.choice(scene_pickupable_objects)