In recent years, polymeric materials have gained wide acceptance in hot water delivery systems. In this research, rigid blends of glassy poly(phenylene ether) (PPE) polymer are studied to determine their suitability in potable hot water environments. Three distinct blends of PPE were prepared for this research: i) a 50/50 blend of PPE and high impact polystyrene (HIPS); ii) a 50/50 blend of PPE and HIPS with the inclusion of an anti-oxidant package and; iii) a blend consisting of capped PPE, crystal polystyrene and styrene-ethyelene-butylene-styrene (SEBS) rubber. Presently, material specimens are being aged for 8000 hours in an 80 C hot potable water bath and an 80 C hot air oven. Various analytical techniques are being utilized to identify degradation mechanisms and molecular changes occurring in each blend. Previous work suggests oxidation of the polymer chains or rubber may be the most likely degradation mechanism for these materials in hot water environments. Recent water diffusion experiments suggest water sorption in the PPE/HIPS blends result in water clustering. The water clusters form a second phase in the PPE/HIPS blends and lead to structural defects (voids) throughout the polymer matrix. It is hypothesized that these structural defects, along with the physical aging of the polymer, are causing drastic reductions in physical properties such as fatigue resistance and toughness. In contrast, the capped PPE blends appear to manage the water sorption process better and its structure does not appear to be prone to clustering or void formation.