Index: leahi_dialin/td/modules/air_trap.py
===================================================================
diff -u -rdf2b51a17a2ccdaf3587f631de7623fa7fcae624 -re7d16bd6881619e5fc2a0bc1a7fd578a9978498e
--- leahi_dialin/td/modules/air_trap.py	(.../air_trap.py)	(revision df2b51a17a2ccdaf3587f631de7623fa7fcae624)
+++ leahi_dialin/td/modules/air_trap.py	(.../air_trap.py)	(revision e7d16bd6881619e5fc2a0bc1a7fd578a9978498e)
@@ -19,32 +19,20 @@
 
 from .constants import RESET, NO_RESET
 from leahi_dialin.common.msg_defs import MsgIds, MsgFieldPositions
+from leahi_dialin.common.td_defs import AirTrapValves, AirTrapLevelSensors, AirTrapLevelSensorsAttributes, AirTrapState
 from leahi_dialin.protocols.CAN import DenaliMessage, DenaliChannels
 from leahi_dialin.utils.base import AbstractSubSystem, publish, DialinEnum
 from leahi_dialin.utils.checks import check_broadcast_interval_override_ms
 from leahi_dialin.utils.conversions import integer_to_bytearray
 
 
-class AirTrapValves(DialinEnum):
-    H13_VALV = 0            # Air trap intake valve
-    H20_VALV = 1            # Air trap outlet valve
-
-@unique
-class AirTrapState(DialinEnum):
-    STATE_CLOSED = 0
-    STATE_OPEN = 1
-
 class TDAirTrap(AbstractSubSystem):
     """
     TDAirTrap
 
     Treatment Delivery (TD) Dialin API sub-class for air trap related commands.
     """
 
-    # Air trap level sensor IDs
-    H17_LOWER_LEVEL_SENSOR = 0
-    H16_UPPER_LEVEL_SENSOR = 1
-
     # Air trap level sensor levels
     AIR_DETECTED_AT_LEVEL = 0
     FLUID_DETECTED_AT_LEVEL = 1
@@ -64,18 +52,26 @@
             self.can_interface.register_receiving_publication_function(channel_id, msg_id,
                                                                        self._handler_air_trap_sync)
 
-        self.h17_lower_level = self.AIR_DETECTED_AT_LEVEL
-        self.h16_upper_level = self.AIR_DETECTED_AT_LEVEL
-        self.h17_lower_level_raw = self.AIR_DETECTED_AT_LEVEL
-        self.h16_upper_level_raw = self.AIR_DETECTED_AT_LEVEL
-        self.h13_valve_state = 0
-        self.h20_valve_state = 0
+        self.air_trap_level_sensors = {
+            AirTrapLevelSensors.H17_LEVEL.name: {
+                AirTrapLevelSensorsAttributes.LEVEL.name: self.AIR_DETECTED_AT_LEVEL,
+                AirTrapLevelSensorsAttributes.RAW.name: self.AIR_DETECTED_AT_LEVEL
+            },
+            AirTrapLevelSensors.H16_LEVEL.name: {
+                AirTrapLevelSensorsAttributes.LEVEL.name: self.AIR_DETECTED_AT_LEVEL,
+                AirTrapLevelSensorsAttributes.RAW.name: self.AIR_DETECTED_AT_LEVEL
+            }
+        }
+        self.air_trap_valve_states = {
+            AirTrapValves.H13_VALV.name: 0,
+            AirTrapValves.H20_VALV.name: 0
+        }
         self.air_control = 0
         self.td_air_trap_timestamp = 0.0
 
-    @publish(["td_air_trap_timestamp", "h17_lower_level", "h16_upper_level",
-              "h17_lower_level_raw", "h16_upper_level_raw",
-              "h13_valve_state","h20_valve_state",
+    @publish(["td_air_trap_timestamp",
+              "air_trap_level_sensors",
+              "air_trap_valve_states",
               "air_control"])
     def _handler_air_trap_sync(self, message, timestamp=0.0):
         """
@@ -101,12 +97,12 @@
         controlling = struct.unpack('i', bytearray(
             message['message'][MsgFieldPositions.START_POS_FIELD_7:MsgFieldPositions.END_POS_FIELD_7]))
 
-        self.h17_lower_level = lower[0]
-        self.h16_upper_level = upper[0]
-        self.h17_lower_level_raw = raw_lower[0]
-        self.h16_upper_level_raw = raw_upper[0]
-        self.h13_valve_state = h13_vlv_st[0]
-        self.h20_valve_state = h20_vlv_st[0]
+        self.air_trap_level_sensors[AirTrapLevelSensors.H17_LEVEL.name][AirTrapLevelSensorsAttributes.LEVEL.name] = lower[0]
+        self.air_trap_level_sensors[AirTrapLevelSensors.H16_LEVEL.name][AirTrapLevelSensorsAttributes.LEVEL.name] = upper[0]
+        self.air_trap_level_sensors[AirTrapLevelSensors.H17_LEVEL.name][AirTrapLevelSensorsAttributes.RAW.name] = raw_lower[0]
+        self.air_trap_level_sensors[AirTrapLevelSensors.H16_LEVEL.name][AirTrapLevelSensorsAttributes.RAW.name] = raw_upper[0]
+        self.air_trap_valve_states[AirTrapValves.H13_VALV.name] = h13_vlv_st[0]
+        self.air_trap_valve_states[AirTrapValves.H20_VALV.name] = h20_vlv_st[0]
         self.air_control = controlling[0]
         self.td_air_trap_timestamp = timestamp