Del. Admin. Code tit. 7, 1000, 1300, 1301, app A
The manufacturer, owner, or operator of an infectious waste treatment unit must carry out an Initial Efficacy Test by using Option 1, 2, or, 3 below, as appropriate for the type of unit, or other procedures, if approved in advance by the Department.
1. Option 1
This option consists of two (2) Phases:
a. Phase 1: Determining the dilution of each test microorganism from the treatment unit for each challenge load (Types A through C) identified in Table C of this Appendix.
(1.) Prepare and sterilize by autoclaving two (2) challenge loads of Type A as identified in Table C. Reserve one challenge load for Phase 2.
(2.) Process each test microorganism in separate runs through the treatment unit. Prior to each run, determine the number of viable test microorganisms in each container, in accordance with applicable manufacturer's recommendations and Standard Methods for the Examination of Water and Wastewater.
(3.) Process each challenge load within thirty (30) minutes after introducing the container of test microorganism into the treatment unit. The container of test microorganisms and the challenge loads must be processed together without the physical and/or chemical agents designed to kill the test microorganisms. For example, in treatment units that use chemical disinfectant(s), an equal volume of liquid (e.g., sterile saline solution (0.9%, volume/volume), phosphate buffer solution, or tap water) must be substituted in place of the chemical disinfectant(s).
(4.) Obtain at least five (5) representative grab samples from the processed residue of each challenge load in accordance with Test Methods for Evaluating Solid Waste Physical/Chemical Methods (SW-846). The number of viable test microorganisms in each grab sample must be determined in accordance with applicable manufacturer's recommendations and Standard Methods for the Examination of Water and Wastewater.
(5.) Calculate the effect of dilution for the treatment unit as follows:
SA = Log N 0A - Log N1A: where Log N1A >=6
where: SA is the log of the number of viable test microorganisms (CFU/gram of waste solids) that were not recovered after processing challenge load Type A.
N 0A is the number of viable test microorganisms (CFU/gram of waste solids) introduced into the treatment unit for challenge load Type A.
N1A is the number of viable test microorganisms (CFU/gram of waste solids) remaining in the processed residue for challenge load Type A.
If Log N1A is less than 6, then the number of viable test microorganisms introduced into the treatment unit must be increased and steps (1) through (6) in Phase 1 must be repeated until LogN1A is > 6. N0A is the inoculum size for challenge load Type A in Phase 2 below.
(6.) Repeat steps (1) through (5) in Phase 1 for challenge loads of infectious waste for Type B and C identified in Table C of this Appendix to determine the effect of dilution (SB and SC respectively).
b. Phase 2: Determining the log kill of each test microorganism in each challenge load (Type A through C) identified in Table C of this Appendix.
(1.) Using the inoculum size (N 0A) determined in Phase 1 above, repeat Phase 1 steps (1) through (5) under the same operating parameters, except that the physical and/or chemical agents designed to kill the test microorganisms must be used.
(2.) Calculate the effectiveness of the treatment unit by subtracting the log of viable cells after the treatment from the log of the viable cells introduced into the treatment unit as inoculum, as follows:
LA = Log N 0A - SA - Log N2A >=6
where: LA is the log kill of the test microorganisms (CFU/gram of waste solids) after treatment in the challenge load Type A.
N 0A is the number of viable test microorganisms (CFU/gram of waste solids) introduced into the treatment unit as the inoculum for challenge load Type A as determined in Phase 1 above.
SA is the log of the number of viable test microorganisms (CFU/gram of waste solids) that were not recovered after processing challenge load Type A in Phase 1 above.
N2A is the log of the number of viable test microorganisms (CFU/gram of waste solids) remaining in the treated residue for challenge load Type A.
(3.) Repeat steps (1) and (2) in Phase 2 for challenge loads Types B and C identified in Table C of this Appendix to determine the effectiveness of the treatment unit (LB and LC respectively).
2. Option 2:
a. Place one microbiological indicator assay containing one of the test microorganisms at numbers greater than one million in a sealed container that remains intact during the treatment. The inside diameter of the container must be no larger than required to contain the assay vial(s). The vial(s) must contain the test microorganisms.
b. Place the container of test microorganisms within a Type A challenge load as identified in Table C of this Appendix.
c. Process the load.
d. Calculate the effectiveness of the treatment unit by subtracting the log of viable cells after treatment from log of viable cells introduced into the treatment unit as inoculum, as follows:
LA = Log N 0 - Log N2A >=6
where: LA is the log kill of the test microorganisms (CFU/gram of waste solids) after treatment in the challenge load Type A.
N 0 is the number of viable test microorganisms (CFU/gram of waste solids) introduced into the treatment unit as the inoculum.
N2A is the log of the number of viable test microorganisms (CFU/gram of waste solids) remaining in the treated residue for challenge load Type A.
e. Repeat steps a through d in this option for challenge loads Types B and C identified in Table C of this Appendix to determine the effectiveness of the treatment unit (LB and LC respectively).
3. Option 3:
a. Place one microbiological indicator assay containing at least one million spores of one of the indicator microorganisms listed in Table B of this Appendix, in a sealed container that remains intact during treatment. The inside diameter of the container must be no larger than required to contain the assay vial(s).
b. Place the container of the indicator microorganisms within a Type A challenge load as identified in Table C of this Appendix.
c. Process the load.
d. Calculate the effectiveness of the treatment unit by subtracting the log of viable cells after treatment from log of viable cells introduced into the treatment unit as inoculum, as follows:
LA = Log N 0 - Log N2A >=6
where: LA is the log kill of the test microorganisms (CFU/gram of waste solids) after treatment in challenge load Type A.
N 0 is the number of viable indicator microorganisms (CFU/gram of waste solids) introduced into the treatment unit as the inoculum.
N2A is the log of the number of viable test microorganisms (CFU/gram of waste solids) remaining in the treated residue for challenge load Type A.
e. Repeat steps a through d in this option for challenge loads Types B and C identified in Table C of this Appendix to determine the effectiveness of the treatment unit (LB and LC, respectively).
APPENDIX A: TABLES
TABLE A: Test Microorganisms
a. Staphylococcus aureus (ATCC 6538)
b. Pseudomonas aeruginosa (ATCC 15442)
c. Candida albicans (ATCC 18804)
d. Trichophyton mentagrophytes (ATCC 9533)
e. MS-2 Bacteriophage (ATCC 15597-B1)
f. Mycobacterium smegmatis (ATCC 14468)
TABLE B: Indicator Microorganisms
a. Bacillus subtilis (ATCC 19659)
b. Bacillus stearothermophilus (ATCC 7953)
c. Bacillus pumilus (ATCC 27142)
TABLE C: Challenge Loads
This Table identifies the three types of challenge loads of infectious waste that must be used as a part of Initial Efficacy Test and Periodic Verification Test(s).
COMPOSITION OF CHALLENGE LOADS % (w/w)
| Type | A | B | C |
| Moisture | <=5 | >=50 | ----- |
| Organic | ---- | ---- | >=70 |
Del. Admin. Code tit. 7, 1000, 1300, 1301, app A