TITLE 35: ENVIRONMENTAL PROTECTION
SUBTITLE F: PUBLIC WATER SUPPLIES
CHAPTER I: POLLUTION CONTROL BOARD
PART 611 PRIMARY DRINKING WATER STANDARDS
SECTION 611.TABLE H CT VALUES (MG·MIN/l) FOR CRYPTOSPORIDIUM INACTIVATION BY CHLORINE DIOXIDE

Section 611.TABLE H CT Values (mg·min/ℓ) for Cryptosporidium Inactivation by Chlorine Dioxide

Log Credit	Water Temperature (°C)
Log Credit	≤ 0.5	1	2	3	5	7	10	15	20	25	30
0.25	159	153	140	128	107	90	69	45	29	19	12
0.5	319	305	279	256	214	180	138	89	58	38	24
1.0	637	610	558	511	429	360	277	179	116	75	49
1.5	956	915	838	767	643	539	415	268	174	113	73
2.0	1275	1220	1117	1023	858	719	553	357	232	150	98
2.5	1594	1525	1396	1278	1072	899	691	447	289	188	122
3.0	1912	1830	1675	1534	1286	1079	830	536	347	226	147

A supplier may use the following equation to determine log credit between the indicated values:

Log credit = (0.001506 ´ (1.09116)^Temp(in
°C))´ CT

BOARD NOTE: Derived from the table at 40 CFR 141.720(b)(1) (2012).

(Source: Amended at 37 Ill. Reg. 1978, effective February 4, 2013)