TSA treats hairspray as an aerosol, and aerosols have certain restrictions when packed in luggage. In hand baggage, you must pack hairspray in your 1-quart bag of toiletries. The can has to be 3.4 oz (100 ml) or smaller.
Hairspray in checked bags is okay but in 18 oz (500 g) containers or smaller. Each passenger can bring up to 70 oz (2 kg) of hazardous toiletries in total (aerosols, perfume, hand sanitizer, nail polish, etc). All hairspray must also have a cap to protect the nozzle.
Traveling With Hairspray Internationally
The rules for traveling with hairspray are identical across the world. The only exception is for countries and airports with the new 3D scanners, with which liquids and aerosols aren’t under the 3.4 oz limit quantities in hand baggage.
Another thing to remember is that the restrictions for your toiletry bag are usually stricter in other countries than in the US. So instead of a reusable toiletry bag, you should pack hairspray in a 20×20 cm, 1 liter Ziploc bag.
Aerosol Hairspray vs Non-Aerosol Hairspray
The rules for hand-release pump nozzles are identical because it’s a liquid. In checked baggage, the 2 kg (70 oz) limit doesn’t apply to non-aerosol hairspray because it isn’t hazardous.
Will Hairspray Explode on Planes?
Hairspray, shaving cream, and other aerosols used to explode when packed in checked baggage. A few decades ago, the cargo hold wasn’t pressurized on airplanes. This caused the release mechanism to break from pressure changes, which caused the contents of the aerosol can to pour out.
Nowadays, cargo compartments are pressurized because some passengers travel with pets in the cargo hold. This doesn’t cause any pressure changes, so any aerosols packed in checked baggage won’t explode anymore.