A greater understanding of the nature of LAL-Test interferences and the use of permissible dilution have minimized inhibition problems. Common interference mechanisms include suboptimal pH, endotoxin aggregation or adsorption, container effects, unbalanced cation concentration, enzyme or protein modification, and non-specific LAL activation. Dilution is the best approach to resolving interferences because over 90% are concentration dependent and are solved by the 1:40 dilution with LAL Reagent Water. Other problems are approached by using dilution plus a specific pretreatment procedure designed to neutralize the offending mechanism.