diff --git a/devices/MK22F51212/drivers/fsl_i2c.c b/devices/MK22F51212/drivers/fsl_i2c.c
index 1414a2d..7bdaa44 100644
--- a/devices/MK22F51212/drivers/fsl_i2c.c
+++ b/devices/MK22F51212/drivers/fsl_i2c.c
@@ -147,7 +147,7 @@ static i2c_isr_t s_i2cMasterIsr;
 static i2c_isr_t s_i2cSlaveIsr;
 
 /* SGF @brief Extern counter to ensure that I2C is always alive */
-uint32_t I2C_Watchdog;
+volatile uint32_t I2C_Watchdog;
 
 /*******************************************************************************
  * Codes
diff --git a/devices/MK22F51212/drivers/fsl_i2c.h b/devices/MK22F51212/drivers/fsl_i2c.h
index ab76648..0f7ba6f 100644
--- a/devices/MK22F51212/drivers/fsl_i2c.h
+++ b/devices/MK22F51212/drivers/fsl_i2c.h
@@ -32,7 +32,7 @@
 
 #include "fsl_common.h"
 
-extern uint32_t I2C_Watchdog;
+extern volatile uint32_t I2C_Watchdog;
 
 /*!
  * @addtogroup i2c_driver