A computer implemented method for tracking chemical applications and providing warnings regarding chemical exposure times, the method comprising: receiving chemical application data indicating the application of a specific chemical to a given field location at a specific date and time. wherein the chemical application data comprises data selected from a group of data comprising: a first chemical type, a concentration, an application amount, time and day of the application, a location of chemical application, and an application method; retrieving chemical characteristic data for the chemical, wherein the chemical characteristic data comprises data selected from a group of data comprising: the aerosolized weight and drift; the chemical life-span, and potential interactions with other chemicals; receiving geo-location data identifying a target application area for the chemical; the method characterised by calculating a probable application area based on a calculation of a potential drift of the chemical beyond the target application area; wherein the calculation of the probable application area is further based at least in part on a factor selected from a group of factors comprising: an aerosolized weight and drift of a given chemical; a chemical lifespan of a given chemical, application method and potential interactions with other chemicals; wherein the probable application area is further based at least in part on environmental factors at the target application area, wherein the environmental factors include an environmental factor selected from a group of environmental factors comprising: wind speed, wind direction, humidity, sunlight levels; cloud cover, barometric pressure, and precipitation events, calculating a geo-fence for the probable application area; calculating an effective period for the probable application area; receiving location data regarding a registered user; comparing the received location data against the calculated geo-fence boundaries for the probable application area; determining whether the registered user is within the probable application area and transmitting a notification to the registered user regarding entry into the probable application area. receiving chemical application data indicating the application of a specific chemical to a given field location at a specific date and time. wherein the chemical application data comprises data selected from a group of data comprising: a first chemical type, a concentration, an application amount, time and day of the application, a location of chemical application, and an application method; retrieving chemical characteristic data for the chemical, wherein the chemical characteristic data comprises data selected from a group of data comprising: the aerosolized weight and drift; the chemical life-span, and potential interactions with other chemicals; receiving geo-location data identifying a target application area for the chemical; the method characterised by calculating a probable application area based on a calculation of a potential drift of the chemical beyond the target application area; wherein the calculation of the probable application area is further based at least in part on a factor selected from a group of factors comprising: an aerosolized weight and drift of a given chemical; a chemical lifespan of a given chemical, application method and potential interactions with other chemicals; wherein the probable application area is further based at least in part on environmental factors at the target application area, wherein the environmental factors include an environmental factor selected from a group of environmental factors comprising: wind speed, wind direction, humidity, sunlight levels; cloud cover, barometric pressure, and precipitation events, calculating a geo-fence for the probable application area; calculating an effective period for the probable application area; receiving location data regarding a registered user; comparing the received location data against the calculated geo-fence boundaries for the probable application area; determining whether the registered user is within the probable application area and transmitting a notification to the registered user regarding entry into the probable application area.