Essential oils and storage

I also have a question as to how to store essential oils...should they be refrigerated; can they be heated before application? how long is the shelf life of an herbal oil?

Refrigeration and heat are both not good as the molecular structure of the oils is altered/distorted/dissipated - and the therapeutic value is compromised.

Store your oils in a dark, cool, dry place.

Shelf life is indefinite.