diff --git a/CO2_Ventilation_Alert.yaml b/CO2_Ventilation_Alert.yaml
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+blueprint:
+  name: CO₂ ventilation alert – Apollo R PRO-1 (LED + buzzer)
+  description: >-
+    Visual and audible CO₂ alerts on an Apollo R PRO-1.
+
+
+    **LED**: off below the "ventilation recommended" level. From that level
+    it turns yellow and fades towards red as CO₂ approaches the "ventilation
+    needed" level; at or above it, it is solid red.
+
+
+    **Buzzer**: at or above the "start beeping" level the beep action is
+    repeated at the chosen interval, but only while CO₂ is NOT dropping.
+    "Dropping" means the newest CO₂ reading is lower than the reading about
+    one minute earlier (taken from a Statistics helper, see the
+    "CO₂ change" input). Beeping stops as soon as CO₂ is falling, at any level.
+  domain: automation
+  input:
+    co2_sensor:
+      name: CO₂ sensor
+      description: The R PRO-1 CO₂ sensor (ppm).
+      selector:
+        entity:
+          filter:
+            - domain: sensor
+              device_class: carbon_dioxide
+    change_sensor:
+      name: CO₂ change over the last minute
+      description: >-
+        A Statistics helper based on the CO₂ sensor above. Settings: State
+        characteristic = "Change", Max age = 1 minute (use 90 s if your
+        sensor reports slower than every ~20 s). Its state is newest reading
+        minus oldest reading in the window, so a negative value means CO₂ is
+        dropping.
+      selector:
+        entity:
+          filter:
+            - domain: sensor
+    led:
+      name: R PRO-1 RGB LED
+      description: The light entity of the R PRO-1 RGB LED.
+      selector:
+        entity:
+          filter:
+            - domain: light
+    beep_action:
+      name: Beep action
+      description: >-
+        Action(s) that make the R PRO-1 beep. Use the ESPHome action of your
+        device, for example `esphome.<your_device>_play_buzzer` with data
+        `song_str: "co2:d=8,o=6,b=180:c,p,c"`. Keep the tune short, it is
+        repeated at the beep interval.
+      default: []
+      selector:
+        action: {}
+    recommended_level:
+      name: Ventilation recommended (ppm)
+      description: LED turns on (yellow) at this level.
+      default: 1000
+      selector:
+        number:
+          min: 400
+          max: 5000
+          step: 50
+          unit_of_measurement: ppm
+          mode: box
+    needed_level:
+      name: Ventilation needed (ppm)
+      description: LED is fully red at this level.
+      default: 1500
+      selector:
+        number:
+          min: 400
+          max: 5000
+          step: 50
+          unit_of_measurement: ppm
+          mode: box
+    beep_level:
+      name: Start beeping (ppm)
+      description: Beeping starts at this level (unless CO₂ is dropping).
+      default: 2000
+      selector:
+        number:
+          min: 400
+          max: 10000
+          step: 50
+          unit_of_measurement: ppm
+          mode: box
+    min_drop:
+      name: Minimum drop to count as "dropping" (ppm)
+      description: >-
+        0 = any decrease stops the beeping. Raise to 5–10 if sensor jitter
+        makes the beeping stop and start at a plateau.
+      default: 0
+      selector:
+        number:
+          min: 0
+          max: 100
+          step: 1
+          unit_of_measurement: ppm
+          mode: box
+    beep_interval:
+      name: Beep repeat interval
+      default: "/30"
+      selector:
+        select:
+          options:
+            - label: Every 10 seconds
+              value: "/10"
+            - label: Every 15 seconds
+              value: "/15"
+            - label: Every 20 seconds
+              value: "/20"
+            - label: Every 30 seconds
+              value: "/30"
+    brightness:
+      name: LED brightness (%)
+      default: 60
+      selector:
+        number:
+          min: 1
+          max: 100
+          step: 1
+          unit_of_measurement: "%"
+          mode: slider
+    led_off_when_ok:
+      name: Turn LED off below "recommended"
+      description: >-
+        If enabled, the LED is switched off when CO₂ is below the
+        recommended level. Disable if you use the LED for other things.
+      default: true
+      selector:
+        boolean: {}
+
+mode: queued
+max: 10
+max_exceeded: silent
+
+variables:
+  co2_sensor: !input co2_sensor
+  change_sensor: !input change_sensor
+  rec_level: !input recommended_level
+  need_level: !input needed_level
+  beep_level: !input beep_level
+  min_drop: !input min_drop
+  led_brightness: !input brightness
+  led_off_when_ok: !input led_off_when_ok
+
+triggers:
+  - trigger: state
+    entity_id: !input co2_sensor
+    id: reading
+  - trigger: time_pattern
+    seconds: !input beep_interval
+    id: beep_tick
+
+actions:
+  - variables:
+      co2: "{{ states(co2_sensor) | float(none) }}"
+      change: "{{ states(change_sensor) | float(0) }}"
+      dropping: "{{ change < -(min_drop | float(0)) }}"
+      span: "{{ [need_level - rec_level, 1] | max }}"
+      frac: >-
+        {{ ([[(co2 - rec_level) / span, 0] | max, 1] | min)
+           if co2 is not none else 0 }}
+      hue: "{{ (60 * (1 - frac)) | round(0) | int }}"
+  - condition: template
+    value_template: "{{ co2 is not none }}"
+  - choose:
+      # --- LED: update on every new CO2 reading -------------------------
+      - conditions:
+          - condition: trigger
+            id: reading
+        sequence:
+          - choose:
+              - conditions:
+                  - condition: template
+                    value_template: "{{ co2 >= rec_level }}"
+                sequence:
+                  - action: light.turn_on
+                    target:
+                      entity_id: !input led
+                    data:
+                      hs_color: "{{ [hue, 100] }}"
+                      brightness_pct: "{{ led_brightness | int }}"
+              - conditions:
+                  - condition: template
+                    value_template: "{{ led_off_when_ok }}"
+                sequence:
+                  - action: light.turn_off
+                    target:
+                      entity_id: !input led
+      # --- Buzzer: repeat while high AND not dropping -------------------
+      - conditions:
+          - condition: trigger
+            id: beep_tick
+          - condition: template
+            value_template: "{{ co2 >= beep_level and not dropping }}"
+        sequence: !input beep_actionblueprint:
+  name: CO₂ ventilation alert – Apollo R PRO-1 (LED + buzzer)
+  description: >-
+    Visual and audible CO₂ alerts on an Apollo R PRO-1.
+
+
+    **LED**: off below the "ventilation recommended" level. From that level
+    it turns yellow and fades towards red as CO₂ approaches the "ventilation
+    needed" level; at or above it, it is solid red.
+
+
+    **Buzzer**: at or above the "start beeping" level the beep action is
+    repeated at the chosen interval, but only while CO₂ is NOT dropping.
+    "Dropping" means the newest CO₂ reading is lower than the reading about
+    one minute earlier (taken from a Statistics helper, see the
+    "CO₂ change" input). Beeping stops as soon as CO₂ is falling, at any level.
+  domain: automation
+  input:
+    co2_sensor:
+      name: CO₂ sensor
+      description: The R PRO-1 CO₂ sensor (ppm).
+      selector:
+        entity:
+          filter:
+            - domain: sensor
+              device_class: carbon_dioxide
+    change_sensor:
+      name: CO₂ change over the last minute
+      description: >-
+        A Statistics helper based on the CO₂ sensor above. Settings: State
+        characteristic = "Change", Max age = 1 minute (use 90 s if your
+        sensor reports slower than every ~20 s). Its state is newest reading
+        minus oldest reading in the window, so a negative value means CO₂ is
+        dropping.
+      selector:
+        entity:
+          filter:
+            - domain: sensor
+    led:
+      name: R PRO-1 RGB LED
+      description: The light entity of the R PRO-1 RGB LED.
+      selector:
+        entity:
+          filter:
+            - domain: light
+    beep_action:
+      name: Beep action
+      description: >-
+        Action(s) that make the R PRO-1 beep. Use the ESPHome action of your
+        device, for example `esphome.<your_device>_play_buzzer` with data
+        `song_str: "co2:d=8,o=6,b=180:c,p,c"`. Keep the tune short, it is
+        repeated at the beep interval.
+      default: []
+      selector:
+        action: {}
+    recommended_level:
+      name: Ventilation recommended (ppm)
+      description: LED turns on (yellow) at this level.
+      default: 1000
+      selector:
+        number:
+          min: 400
+          max: 5000
+          step: 50
+          unit_of_measurement: ppm
+          mode: box
+    needed_level:
+      name: Ventilation needed (ppm)
+      description: LED is fully red at this level.
+      default: 1500
+      selector:
+        number:
+          min: 400
+          max: 5000
+          step: 50
+          unit_of_measurement: ppm
+          mode: box
+    beep_level:
+      name: Start beeping (ppm)
+      description: Beeping starts at this level (unless CO₂ is dropping).
+      default: 2000
+      selector:
+        number:
+          min: 400
+          max: 10000
+          step: 50
+          unit_of_measurement: ppm
+          mode: box
+    min_drop:
+      name: Minimum drop to count as "dropping" (ppm)
+      description: >-
+        0 = any decrease stops the beeping. Raise to 5–10 if sensor jitter
+        makes the beeping stop and start at a plateau.
+      default: 0
+      selector:
+        number:
+          min: 0
+          max: 100
+          step: 1
+          unit_of_measurement: ppm
+          mode: box
+    beep_interval:
+      name: Beep repeat interval
+      default: "/30"
+      selector:
+        select:
+          options:
+            - label: Every 10 seconds
+              value: "/10"
+            - label: Every 15 seconds
+              value: "/15"
+            - label: Every 20 seconds
+              value: "/20"
+            - label: Every 30 seconds
+              value: "/30"
+    brightness:
+      name: LED brightness (%)
+      default: 60
+      selector:
+        number:
+          min: 1
+          max: 100
+          step: 1
+          unit_of_measurement: "%"
+          mode: slider
+    led_off_when_ok:
+      name: Turn LED off below "recommended"
+      description: >-
+        If enabled, the LED is switched off when CO₂ is below the
+        recommended level. Disable if you use the LED for other things.
+      default: true
+      selector:
+        boolean: {}
+
+mode: queued
+max: 10
+max_exceeded: silent
+
+variables:
+  co2_sensor: !input co2_sensor
+  change_sensor: !input change_sensor
+  rec_level: !input recommended_level
+  need_level: !input needed_level
+  beep_level: !input beep_level
+  min_drop: !input min_drop
+  led_brightness: !input brightness
+  led_off_when_ok: !input led_off_when_ok
+
+triggers:
+  - trigger: state
+    entity_id: !input co2_sensor
+    id: reading
+  - trigger: time_pattern
+    seconds: !input beep_interval
+    id: beep_tick
+
+actions:
+  - variables:
+      co2: "{{ states(co2_sensor) | float(none) }}"
+      change: "{{ states(change_sensor) | float(0) }}"
+      dropping: "{{ change < -(min_drop | float(0)) }}"
+      span: "{{ [need_level - rec_level, 1] | max }}"
+      frac: >-
+        {{ ([[(co2 - rec_level) / span, 0] | max, 1] | min)
+           if co2 is not none else 0 }}
+      hue: "{{ (60 * (1 - frac)) | round(0) | int }}"
+  - condition: template
+    value_template: "{{ co2 is not none }}"
+  - choose:
+      # --- LED: update on every new CO2 reading -------------------------
+      - conditions:
+          - condition: trigger
+            id: reading
+        sequence:
+          - choose:
+              - conditions:
+                  - condition: template
+                    value_template: "{{ co2 >= rec_level }}"
+                sequence:
+                  - action: light.turn_on
+                    target:
+                      entity_id: !input led
+                    data:
+                      hs_color: "{{ [hue, 100] }}"
+                      brightness_pct: "{{ led_brightness | int }}"
+              - conditions:
+                  - condition: template
+                    value_template: "{{ led_off_when_ok }}"
+                sequence:
+                  - action: light.turn_off
+                    target:
+                      entity_id: !input led
+      # --- Buzzer: repeat while high AND not dropping -------------------
+      - conditions:
+          - condition: trigger
+            id: beep_tick
+          - condition: template
+            value_template: "{{ co2 >= beep_level and not dropping }}"
+        sequence: !input beep_action