diff --git a/fw/Core/Src/main.c b/fw/Core/Src/main.c
index 387c409..65c85c2 100644
--- a/fw/Core/Src/main.c
+++ b/fw/Core/Src/main.c
@@ -126,7 +126,7 @@ sps30_data_t PM_SPS30;
 /* VOC related varibles */
 uint16_t voc_ticks_compensated;
 uint16_t voc_ticks;
-uint16_t voc_index;
+uint32_t voc_index;
 
 /* Struct to store the sensor config */
 config_t sensor_config;