From b26b1df143450b7ad8c34e03985128996e379d76 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ab=C3=ADlio=20Costa?= <abmantis@users.noreply.github.com>
Date: Mon, 22 Sep 2025 15:19:31 +0100
Subject: [PATCH] Fix unitless converter missing valid units (#152665)

---
 homeassistant/util/unit_conversion.py    | 2 ++
 tests/components/sensor/test_recorder.py | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/homeassistant/util/unit_conversion.py b/homeassistant/util/unit_conversion.py
index be4372573f1b..b2938b249b87 100644
--- a/homeassistant/util/unit_conversion.py
+++ b/homeassistant/util/unit_conversion.py
@@ -742,6 +742,8 @@ class UnitlessRatioConverter(BaseUnitConverter):
     }
     VALID_UNITS = {
         None,
+        CONCENTRATION_PARTS_PER_BILLION,
+        CONCENTRATION_PARTS_PER_MILLION,
         PERCENTAGE,
     }
 
diff --git a/tests/components/sensor/test_recorder.py b/tests/components/sensor/test_recorder.py
index 50754d2244b3..695202b67c81 100644
--- a/tests/components/sensor/test_recorder.py
+++ b/tests/components/sensor/test_recorder.py
@@ -5201,7 +5201,7 @@ async def test_validate_statistics_unit_ignore_device_class(
             BATTERY_SENSOR_ATTRIBUTES,
             "%",
             None,
-            "%, <None>",
+            "%, <None>, ppb, ppm",
         ),
     ],
 )