Check the Transportation Security Administration's (TSA) current
carry-on quantity rules and exceptions at
http://www.tsa.gov/311/index.shtm, and related links. For security reasons, with some exceptions, TSA currently allows you to carry on containers no larger than three ounces.,
Next, separate medicinal aerosols from personal toilet items.
As a rule of thumb, aerosols that are personal, medicinal, and toilet items are those that are sprayed on your body. These can be carried on board (following
TSA's 3-1-1 rule) or in
checked baggage.
Other aerosols, if allowed, should be packed in
checked baggage, regardless of size. The DOT regulations forbid flammable aerosols except in the personal, medicinal, and toilet items discussed above - you may not travel with other flammable aerosols in any baggage.
There may be some pump-spray versions of the above items that are not considered hazardous materials.
Travel with the cap on your aerosol can, whether it is in checked or
carry-on baggage.
Finally, follow the
safety tips and
quantity limitations on the following pages, when you travel with aerosols, whether in
carry-on or
checked baggage!