diff --git a/homeassistant/components/fireservicerota/coordinator.py b/homeassistant/components/fireservicerota/coordinator.py
index 35f839b3bdb..14a8c40e469 100644
--- a/homeassistant/components/fireservicerota/coordinator.py
+++ b/homeassistant/components/fireservicerota/coordinator.py
@@ -54,7 +54,9 @@ class FireServiceUpdateCoordinator(DataUpdateCoordinator[dict | None]):
 class FireServiceRotaOauth:
     """Handle authentication tokens."""
 
-    def __init__(self, hass, entry, fsr):
+    def __init__(
+        self, hass: HomeAssistant, entry: ConfigEntry, fsr: FireServiceRota
+    ) -> None:
         """Initialize the oauth object."""
         self._hass = hass
         self._entry = entry
@@ -94,7 +96,7 @@ class FireServiceRotaOauth:
 class FireServiceRotaWebSocket:
     """Define a FireServiceRota websocket manager object."""
 
-    def __init__(self, hass, entry):
+    def __init__(self, hass: HomeAssistant, entry: ConfigEntry) -> None:
         """Initialize the websocket object."""
         self._hass = hass
         self._entry = entry
@@ -128,7 +130,7 @@ class FireServiceRotaWebSocket:
 class FireServiceRotaClient:
     """Getting the latest data from fireservicerota."""
 
-    def __init__(self, hass, entry):
+    def __init__(self, hass: HomeAssistant, entry: ConfigEntry) -> None:
         """Initialize the data object."""
         self._hass = hass
         self._entry = entry
diff --git a/homeassistant/components/fireservicerota/sensor.py b/homeassistant/components/fireservicerota/sensor.py
index 864838ddaff..b09d1295025 100644
--- a/homeassistant/components/fireservicerota/sensor.py
+++ b/homeassistant/components/fireservicerota/sensor.py
@@ -11,6 +11,7 @@ from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.helpers.restore_state import RestoreEntity
 
 from .const import DATA_CLIENT, DOMAIN as FIRESERVICEROTA_DOMAIN
+from .coordinator import FireServiceRotaClient
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -32,13 +33,13 @@ class IncidentsSensor(RestoreEntity, SensorEntity):
     _attr_has_entity_name = True
     _attr_translation_key = "incidents"
 
-    def __init__(self, client):
+    def __init__(self, client: FireServiceRotaClient) -> None:
         """Initialize."""
         self._client = client
         self._entry_id = self._client.entry_id
         self._attr_unique_id = f"{self._client.unique_id}_Incidents"
-        self._state = None
-        self._state_attributes = {}
+        self._state: str | None = None
+        self._state_attributes: dict[str, Any] = {}
 
     @property
     def icon(self) -> str:
@@ -52,7 +53,7 @@ class IncidentsSensor(RestoreEntity, SensorEntity):
         return "mdi:fire-truck"
 
     @property
-    def native_value(self) -> str:
+    def native_value(self) -> str | None:
         """Return the state of the sensor."""
         return self._state
 
diff --git a/homeassistant/components/fireservicerota/switch.py b/homeassistant/components/fireservicerota/switch.py
index 22287653788..affd46c91bd 100644
--- a/homeassistant/components/fireservicerota/switch.py
+++ b/homeassistant/components/fireservicerota/switch.py
@@ -10,6 +10,7 @@ from homeassistant.helpers.dispatcher import async_dispatcher_connect
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 
 from .const import DATA_CLIENT, DATA_COORDINATOR, DOMAIN as FIRESERVICEROTA_DOMAIN
+from .coordinator import FireServiceRotaClient, FireServiceUpdateCoordinator
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -32,15 +33,20 @@ class ResponseSwitch(SwitchEntity):
     _attr_has_entity_name = True
     _attr_translation_key = "incident_response"
 
-    def __init__(self, coordinator, client, entry):
+    def __init__(
+        self,
+        coordinator: FireServiceUpdateCoordinator,
+        client: FireServiceRotaClient,
+        entry: ConfigEntry,
+    ) -> None:
         """Initialize."""
         self._coordinator = coordinator
         self._client = client
         self._attr_unique_id = f"{entry.unique_id}_Response"
         self._entry_id = entry.entry_id
 
-        self._state = None
-        self._state_attributes = {}
+        self._state: bool | None = None
+        self._state_attributes: dict[str, Any] = {}
         self._state_icon = None
 
     @property
@@ -54,7 +60,7 @@ class ResponseSwitch(SwitchEntity):
         return "mdi:forum"
 
     @property
-    def is_on(self) -> bool:
+    def is_on(self) -> bool | None:
         """Get the assumed state of the switch."""
         return self._state