Wet chemical extinguishers employ a pressurized solution of alkali salts in water and are particularly effective against fats and cooking oils but not against petroleum products.
Putu ugunsdzēšamos aparātus izmanto, dzēšot ne tikai degošus A grupas materiālus, bet arī viegli uzliesmojošus šķidrumus (rūpnieciskās ziežeļļas, degvielu, krāsas), ko parasti sauc par B grupu.