What is the shelf life of foam and what is the recommended method of storage?

Since air filter foam can be subjected to a variety of environments beyond our control, Universal does not publish a life expectancy. “Shelf life” is not typically used to describe longevity because it is a relative term. 

The ideal storage condition for polyurethane foam is a cool, dry, dark environment. Conditions that adversely affect the media are high temperature, humidity, and ultraviolet light. Foam media also degrades when exposed to solvents and sulfates, such as engine exhaust. Reduced foam life depends upon the degree of difference from the ideal conditions the foam is stored. 

Customer feedback indicates that controlling relative humidity between 40%-80% and temperature between 40F-90F yields an acceptable environment. Covering the filters with dark plastic will keep media dry and protected from ultraviolet light. 

We do not recommend storing foam filters for several months or years at a time. Instead, purchase cost-effective quantities and keep adequate inventory for no more than a few months.