The formation of photoinduced crystals and haze has become a challenge for 193nm photolithography high volume manufacturing (1-6). Extensive work has been performed to develop alternative to piranha chemistry for photomask cleaning processes in an attempt to eliminate the incidence of clean induced ammonium sulfate crystal formation (9-13). However, additional factors are impacting 193nm reticle optical quality. Sources of molecular contaminants such as environmental factors, outgasing from pellicle and reticle storage material can generate varieties of photoinduced crystals over the reticle useable lifetime (5-6). This paper will quantify and rank contributing factors for crystals generated under high energy UV exposure. A broad range of analytical and metrology techniques (FTIR, IC, TD-GC/MS, Inorganics impinger, AIMSTM, KLA Starlight, UV 172nm) and improvements in technique sensitivity were developed in order to identify crystal structure, quantify photogenerated contaminants levels and assess wafer printability impact. Engineering systems aimed at minimizing organic and inorganic molecular contaminants levels will be suggested.