diff --git a/lib/eclss-api/src/lib.rs b/lib/eclss-api/src/lib.rs
index 0298b7e..be0d20f 100644
--- a/lib/eclss-api/src/lib.rs
+++ b/lib/eclss-api/src/lib.rs
@@ -13,6 +13,8 @@ pub struct Metrics {
     pub co2_ppm: heapless::Vec<Measurement, MAX_SENSORS>,
     pub eco2_ppm: heapless::Vec<Measurement, MAX_SENSORS>,
     pub tvoc_ppb: heapless::Vec<Measurement, MAX_SENSORS>,
+    pub tvoc_iaq_index: heapless::Vec<Measurement, MAX_SENSORS>,
+    pub nox_iaq_index: heapless::Vec<Measurement, MAX_SENSORS>,
     pub pressure_hpa: heapless::Vec<Measurement, MAX_SENSORS>,
     pub sensor_errors: heapless::Vec<Measurement, MAX_SENSORS>,
 }
diff --git a/lib/eclss/src/metrics.rs b/lib/eclss/src/metrics.rs
index 3de52a5..4749c20 100644
--- a/lib/eclss/src/metrics.rs
+++ b/lib/eclss/src/metrics.rs
@@ -24,6 +24,10 @@ pub struct SensorMetrics {
     #[cfg_attr(feature = "serde", serde(serialize_with = "serialize_metric"))]
     pub tvoc_ppb: GaugeFamily<'static, TVOC_METRICS, SensorName>,
     #[cfg_attr(feature = "serde", serde(serialize_with = "serialize_metric"))]
+    pub tvoc_iaq_index: GaugeFamily<'static, TVOC_IAQ_METRICS, SensorName>,
+    #[cfg_attr(feature = "serde", serde(serialize_with = "serialize_metric"))]
+    pub nox_iaq_index: GaugeFamily<'static, NOX_IAQ_METRICS, SensorName>,
+    #[cfg_attr(feature = "serde", serde(serialize_with = "serialize_metric"))]
     #[serde(skip)]
     pub pm_conc: GaugeFamily<'static, PM_CONC_METRICS, DiameterLabel>,
     // #[cfg_attr(feature = "serde", serde(serialize_with =
@@ -52,6 +56,9 @@ pub const HUMIDITY_METRICS: usize =
 pub const PRESSURE_METRICS: usize = count_features!("bme680");
 pub const VOC_RESISTANCE_METRICS: usize = count_features!("bme680");
 pub const TVOC_METRICS: usize = count_features!("sgp30", "bme680", "ens160");
+// IAQ from 1-500
+pub const TVOC_IAQ_METRICS: usize = count_features!("sen55", "bme680", "sgp40");
+pub const NOX_IAQ_METRICS: usize = count_features!("sen55");
 pub const PM_CONC_METRICS: usize =
     // PMSA003I exposes three particulate concentration metrics
     (count_features!("pmsa003i") * 3)
@@ -103,6 +110,14 @@ impl SensorMetrics {
                 .with_help("Total Volatile Organic Compounds (VOC) in parts per billion (ppb)")
                 .with_unit("ppb")
                 .build_labeled::<_, SensorName, TVOC_METRICS>(),
+            tvoc_iaq_index: MetricBuilder::new("tvoc_iaq_index")
+                .with_help("Total Volatile Organic Compounds (VOC) Indoor Air Quality (IAQ) Index from 0-500")
+                .with_unit("IAQ index")
+                .build_labeled::<_, SensorName, TVOC_IAQ_METRICS>(),
+            nox_iaq_index: MetricBuilder::new("nox_iaq_index")
+                .with_help("Nitrogen Oxides (NOx) Indoor Air Quality (IAQ) Index from 0-500")
+                .with_unit("IAQ index")
+                .build_labeled::<_, SensorName, NOX_IAQ_METRICS>(),
             pm_conc: MetricBuilder::new("pm_concentration_ug_m3")
                 .with_help("Particulate matter concentration in ug/m^3")
                 .with_unit("ug/m^3")
@@ -126,6 +141,8 @@ impl SensorMetrics {
         self.pressure_hpa.fmt_metric(f)?;
         self.gas_resistance.fmt_metric(f)?;
         self.tvoc_ppb.fmt_metric(f)?;
+        self.tvoc_iaq_index.fmt_metric(f)?;
+        self.nox_iaq_index.fmt_metric(f)?;
         self.pm_conc.fmt_metric(f)?;
         self.pm_count.fmt_metric(f)?;
         self.sensor_errors.fmt_metric(f)?;
diff --git a/lib/eclss/src/sensor/sen55.rs b/lib/eclss/src/sensor/sen55.rs
index 5621c0e..98f6d11 100644
--- a/lib/eclss/src/sensor/sen55.rs
+++ b/lib/eclss/src/sensor/sen55.rs
@@ -23,6 +23,8 @@ pub struct Sen55<I: 'static, D> {
     pm2_5: &'static Gauge,
     pm4_0: &'static Gauge,
     pm10_0: &'static Gauge,
+    nox_index: &'static Gauge,
+    voc_index: &'static Gauge,
     delay: D,
     abs_humidity_interval: usize,
     polls: Wrapping<usize>,
@@ -53,6 +55,8 @@ where
             pm2_5: metrics.pm_conc.register(diameter("2.5")).unwrap(),
             pm4_0: metrics.pm_conc.register(diameter("4.0")).unwrap(),
             pm10_0: metrics.pm_conc.register(diameter("10.0")).unwrap(),
+            nox_index: metrics.nox_iaq_index.register(NAME).unwrap(),
+            voc_index: metrics.tvoc_iaq_index.register(NAME).unwrap(),
             delay,
             polls: Wrapping(0),
             abs_humidity_interval: 1,
@@ -109,11 +113,12 @@ where
             .context("failed to read SEN5x measurement data")?;
         let temp = measurement.temp_c();
         let rel_humidity = measurement.relative_humidity();
-        let voc = measurement.voc_index();
+        let voc_index = measurement.voc_index();
         let nox_index = measurement.nox_index();
 
         debug!(
-            "{NAME}: Temp: {temp:?}°C, Humidity: {rel_humidity:?}, VOC: {voc:?}, NOx: {nox_index:?}, ready: {ready}"
+            "{NAME}: Temp: {temp:?}°C, Humidity: {rel_humidity:?}, \
+            VOC Index: {voc_index:?}, NOx Index: {nox_index:?}, ready: {ready}"
         );
         let pm1_0 = measurement.pm1_0();
         let pm2_5 = measurement.pm2_5();
@@ -122,14 +127,7 @@ where
         debug!("{NAME}: PM1.0: {pm1_0:?}, PM2.5: {pm2_5:?}, PM4.0: {pm4_0:?}, PM10.0: {pm10_0:?}, ready: {ready}");
 
         if ready {
-            if let Some(humidity) = rel_humidity {
-                self.rel_humidity.set_value(humidity as f64);
-            }
-            if let Some(temp) = temp {
-                self.temp.set_value(temp as f64);
-            }
-
-            macro_rules! update_particulates {
+            macro_rules! update_metrics {
                 ($($name:ident),+) => {
                     $(
                         if let Some(pm) = $name {
@@ -139,7 +137,16 @@ where
                 }
             }
 
-            update_particulates!(pm1_0, pm2_5, pm4_0, pm10_0);
+            update_metrics!(
+                rel_humidity,
+                temp,
+                nox_index,
+                voc_index,
+                pm1_0,
+                pm2_5,
+                pm4_0,
+                pm10_0
+            );
 
             if let (Some(temp), Some(humidity)) = (temp, rel_humidity) {
                 if self.polls.0 % self.abs_humidity_interval == 0 {