Parameters to be tested six-monthly are as specified in Table G-1, provided however, that (i) if a Critical Parameter that is specified for testing every six months is found to be greater than 90% of the allowed limit, the parameter shall thereafter be tested monthly until it is less than 90% of the allowed limit, at which point it reverts back to six monthly testing, and (ii) if a Non-Critical Parameter that is specified for testing every six months is found to be greater than 10% of the allowed limit, the parameter shall thereafter be tested quarterly until it is less than 90% of the allowed limit, at which point it reverts back to six monthly testing.