1：Experimental Design and Method Selection:

The study utilized a CDC biofilm reactor for growing biofilms under high shear and continuous flow, following ASTM standards. Pulsed light (PL) was used for disinfection, and real-time PCR was employed for detection of parasite DNA in biofilms.

2：Sample Selection and Data Sources:

Microbial species included Listeria monocytogenes, Bacillus cereus, Salmonella typhimurium, Escherichia coli, Giardia lamblia cysts, and Cryptosporidium parvum oocysts, sourced from ATCC and Waterborne Inc. Biofilms were grown on PVC and stainless steel coupons.

3：List of Experimental Equipment and Materials:

CDC biofilm reactor, PUV machine from Samtech Ltd, nutrient agar and broth, sterile PBS, DNA extraction kits from Roche, primers and probes from Tib Molbiol, Nanocycler device from Roche Diagnostics, inverted microscope (Olympus CKX41) with camera (Olympus IX2-SLP), haemocytometer.

4：Experimental Procedures and Operational Workflow:

Biofilms were grown for 72-96 hours in CDC reactor, coupons were rinsed and scraped for analysis. PL treatment was applied at varying UV doses, and inactivation was measured via plate counts and PCR. DNA extraction and RT-PCR were performed for parasite detection.

5：Data Analysis Methods:

Data were analyzed using Student's t-tests and ANOVA with MINITAB software, with log10 reduction calculations for inactivation rates.