Because these are 2 different applications, we would recommend a different unit for best results. For fire fighting you need more volume and less pressure. View our Fire Ranger. For spraying you look for less volume and more pressure. You could use this unit (Field Boss 365) to spray water for fire suppression but it would be limited as you may not have enough volume. This unit will pump up to 50 PSI with restricted flow. Please reach out if you would like more information on this.