Minimizing ozone-laden outside air exposure is key, so the house is usually better than the garage, and the air in a closet has already had the vast majority of the air's oxidizing ozone attracted out to the other materials in the house and closet. Temperature plays only a minor role, but high temperatures correspond to poor summer air quality in many locales.
Near an outside vent is worst. (actually, atop a moving car is the very worst). Covering the bars with a bag is a big improvement. Covering a row of bikes with a tarp prevents corrosive dust buildup as well as excluding ozone, but a tarp shouldn't extend quite to ground level lest humidity from the floor gets trapped within.
Storing hoods alone is easy, just package them up so air currents can't get to 'em. A couple of layers of paper will do fine, or a box within a box. Ozone molecules will stick to almost anything that's in the way of the hoods.
David Snyder using a well-sealed garage to good effect in Auburn, CA usa
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> Having just paid a great deal for some NOS rubber hoods, any suggestions
> on care and feeding? I know enough not to Armour All them.
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> Bill Koonce
> Seattle, WA