Add ppb as a valid UOM for sensor/number NO device class (#161379)

homeassistant/components/number/const.py

@@ -253,7 +253,7 @@ class NumberDeviceClass(StrEnum):
     NITROGEN_MONOXIDE = "nitrogen_monoxide"
     """Amount of NO.
 
-    Unit of measurement: `μg/m³`
+    Unit of measurement: `ppb` (parts per billion), `μg/m³`
     """
 
     NITROUS_OXIDE = "nitrous_oxide"
@@ -521,7 +521,10 @@ DEVICE_CLASS_UNITS: dict[NumberDeviceClass, set[type[StrEnum] | str | None]] = {
         CONCENTRATION_PARTS_PER_BILLION,
         CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
     },
-    NumberDeviceClass.NITROGEN_MONOXIDE: {CONCENTRATION_MICROGRAMS_PER_CUBIC_METER},
+    NumberDeviceClass.NITROGEN_MONOXIDE: {
+        CONCENTRATION_PARTS_PER_BILLION,
+        CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
+    },
     NumberDeviceClass.NITROUS_OXIDE: {CONCENTRATION_MICROGRAMS_PER_CUBIC_METER},
     NumberDeviceClass.OZONE: {
         CONCENTRATION_PARTS_PER_BILLION,

homeassistant/components/recorder/statistics.py

@@ -60,6 +60,7 @@ from homeassistant.util.unit_conversion import (
     MassConverter,
     MassVolumeConcentrationConverter,
     NitrogenDioxideConcentrationConverter,
+    NitrogenMonoxideConcentrationConverter,
     OzoneConcentrationConverter,
     PowerConverter,
     PressureConverter,
@@ -228,6 +229,7 @@ _PRIMARY_UNIT_CONVERTERS: list[type[BaseUnitConverter]] = [
 _SECONDARY_UNIT_CONVERTERS: list[type[BaseUnitConverter]] = [
     CarbonMonoxideConcentrationConverter,
     NitrogenDioxideConcentrationConverter,
+    NitrogenMonoxideConcentrationConverter,
     OzoneConcentrationConverter,
     SulphurDioxideConcentrationConverter,
     TemperatureDeltaConverter,

homeassistant/components/recorder/websocket_api.py

@@ -34,6 +34,7 @@ from homeassistant.util.unit_conversion import (
     MassConverter,
     MassVolumeConcentrationConverter,
     NitrogenDioxideConcentrationConverter,
+    NitrogenMonoxideConcentrationConverter,
     OzoneConcentrationConverter,
     PowerConverter,
     PressureConverter,
@@ -94,6 +95,9 @@ UNIT_SCHEMA = vol.Schema(
         vol.Optional("nitrogen_dioxide"): vol.In(
             NitrogenDioxideConcentrationConverter.VALID_UNITS
         ),
+        vol.Optional("nitrogen_monoxide"): vol.In(
+            NitrogenMonoxideConcentrationConverter.VALID_UNITS
+        ),
         vol.Optional("ozone"): vol.In(OzoneConcentrationConverter.VALID_UNITS),
         vol.Optional("power"): vol.In(PowerConverter.VALID_UNITS),
         vol.Optional("pressure"): vol.In(PressureConverter.VALID_UNITS),

homeassistant/components/sensor/const.py

@@ -64,6 +64,7 @@ from homeassistant.util.unit_conversion import (
     MassConverter,
     MassVolumeConcentrationConverter,
     NitrogenDioxideConcentrationConverter,
+    NitrogenMonoxideConcentrationConverter,
     OzoneConcentrationConverter,
     PowerConverter,
     PressureConverter,
@@ -291,7 +292,7 @@ class SensorDeviceClass(StrEnum):
     NITROGEN_MONOXIDE = "nitrogen_monoxide"
     """Amount of NO.
 
-    Unit of measurement: `μg/m³`
+    Unit of measurement: `ppb` (parts per billion), `μg/m³`
     """
 
     NITROUS_OXIDE = "nitrous_oxide"
@@ -566,6 +567,7 @@ UNIT_CONVERTERS: dict[SensorDeviceClass | str | None, type[BaseUnitConverter]] =
     SensorDeviceClass.ENERGY_STORAGE: EnergyConverter,
     SensorDeviceClass.GAS: VolumeConverter,
     SensorDeviceClass.NITROGEN_DIOXIDE: NitrogenDioxideConcentrationConverter,
+    SensorDeviceClass.NITROGEN_MONOXIDE: NitrogenMonoxideConcentrationConverter,
     SensorDeviceClass.OZONE: OzoneConcentrationConverter,
     SensorDeviceClass.POWER: PowerConverter,
     SensorDeviceClass.POWER_FACTOR: UnitlessRatioConverter,
@@ -639,7 +641,10 @@ DEVICE_CLASS_UNITS: dict[SensorDeviceClass, set[type[StrEnum] | str | None]] = {
         CONCENTRATION_PARTS_PER_BILLION,
         CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
     },
-    SensorDeviceClass.NITROGEN_MONOXIDE: {CONCENTRATION_MICROGRAMS_PER_CUBIC_METER},
+    SensorDeviceClass.NITROGEN_MONOXIDE: {
+        CONCENTRATION_PARTS_PER_BILLION,
+        CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
+    },
     SensorDeviceClass.NITROUS_OXIDE: {CONCENTRATION_MICROGRAMS_PER_CUBIC_METER},
     SensorDeviceClass.OZONE: {
         CONCENTRATION_PARTS_PER_BILLION,

homeassistant/util/unit_conversion.py

@@ -104,6 +104,7 @@ _AMBIENT_IDEAL_GAS_MOLAR_VOLUME = (  # m3⋅mol⁻¹
 # Molar masses in g⋅mol⁻¹
 _CARBON_MONOXIDE_MOLAR_MASS = 28.01
 _NITROGEN_DIOXIDE_MOLAR_MASS = 46.0055
+_NITROGEN_MONOXIDE_MOLAR_MASS = 30.0061
 _OZONE_MOLAR_MASS = 48.00
 _SULPHUR_DIOXIDE_MOLAR_MASS = 64.066
 
@@ -502,6 +503,22 @@ class NitrogenDioxideConcentrationConverter(BaseUnitConverter):
     }
 
 
+class NitrogenMonoxideConcentrationConverter(BaseUnitConverter):
+    """Convert nitrogen monoxide ratio to mass per volume."""
+
+    UNIT_CLASS = "nitrogen_monoxide"
+    _UNIT_CONVERSION: dict[str | None, float] = {
+        CONCENTRATION_PARTS_PER_BILLION: 1e9,
+        CONCENTRATION_MICROGRAMS_PER_CUBIC_METER: (
+            _NITROGEN_MONOXIDE_MOLAR_MASS / _AMBIENT_IDEAL_GAS_MOLAR_VOLUME * 1e6
+        ),
+    }
+    VALID_UNITS = {
+        CONCENTRATION_PARTS_PER_BILLION,
+        CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
+    }
+
+
 class OzoneConcentrationConverter(BaseUnitConverter):
     """Convert ozone ratio to mass per volume."""
 

tests/components/sensor/test_init.py

@@ -3107,7 +3107,6 @@ def test_device_class_converters_are_complete() -> None:
         SensorDeviceClass.IRRADIANCE,
         SensorDeviceClass.MOISTURE,
         SensorDeviceClass.MONETARY,
-        SensorDeviceClass.NITROGEN_MONOXIDE,
         SensorDeviceClass.NITROUS_OXIDE,
         SensorDeviceClass.PH,
         SensorDeviceClass.PM1,

tests/util/test_unit_conversion.py

@@ -57,6 +57,7 @@ from homeassistant.util.unit_conversion import (
     MassConverter,
     MassVolumeConcentrationConverter,
     NitrogenDioxideConcentrationConverter,
+    NitrogenMonoxideConcentrationConverter,
     OzoneConcentrationConverter,
     PowerConverter,
     PressureConverter,
@@ -107,6 +108,7 @@ _ALL_CONVERTERS: dict[type[BaseUnitConverter], list[str | None]] = {
         VolumeConverter,
         VolumeFlowRateConverter,
         NitrogenDioxideConcentrationConverter,
+        NitrogenMonoxideConcentrationConverter,
         SulphurDioxideConcentrationConverter,
     )
 }
@@ -169,6 +171,11 @@ _GET_UNIT_RATIO: dict[type[BaseUnitConverter], tuple[str | None, str | None, flo
         CONCENTRATION_PARTS_PER_BILLION,
         1.912503,
     ),
+    NitrogenMonoxideConcentrationConverter: (
+        CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
+        CONCENTRATION_PARTS_PER_BILLION,
+        1.247389,
+    ),
     OzoneConcentrationConverter: (
         CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
         CONCENTRATION_PARTS_PER_BILLION,
@@ -407,6 +414,20 @@ _CONVERTED_VALUE: dict[
             CONCENTRATION_PARTS_PER_BILLION,
         ),
     ],
+    NitrogenMonoxideConcentrationConverter: [
+        (
+            1,
+            CONCENTRATION_PARTS_PER_BILLION,
+            1.247389,
+            CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
+        ),
+        (
+            120,
+            CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
+            96.200906,
+            CONCENTRATION_PARTS_PER_BILLION,
+        ),
+    ],
     ConductivityConverter: [
         (
             5,