An aerosol is a mixture made up of solid particles suspended in gas within a pressurized container. The most common use of aerosols is in hairspray and spray paint. When releasing the container's pressure, typically with an attached nozzle, the expanding gas projects the particles in the form of a fine mist. Due to this pressure, a puncture in the container will unintentionally release the contents at an accelerated rate. Stopping this type of pressurized leak requires a different approach than that of an unpressurized liquid leak.
Point the leak away from your face to avoid getting the aerosol solution in your eyes.
Apply a small piece of duct tape to the container over the location of the leak. Apply pressure with the thumb and smooth the tape over the puncture site. Duct tape and its adhesive are waterproof, which allows it to create an airtight seal regardless of if the area is wet or not. The high pressure contained within the canister can loosen the small piece of tape over time, so this is only a temporary fix that will allow you to further reinforce the seal without the container continuing to spray its contents.
Reinforce the temporary seal by wrapping additional duct tape tightly around the container at least three times. Make sure the tape covers the container at least two inches above and below the puncture. This provides a full coverage airtight seal that will permanently stop the leak.
Aerosol solutions are potentially flammable. Do not attempt this repair while near an open flame, heating element or lit cigarette.