Ultraviolet (UV) Radiation Tests
Ultraviolet radiation tests assess the intensity, distribution, and effectiveness of UV light sources used for disinfection, sterilization, and contamination control. These tests are critical in hospitals, cleanrooms, pharmaceutical facilities, food processing, and water treatment plants, where UV systems are used for microbial control.

1. Purpose of UV Radiation Testing
Ensures UV system effectiveness for disinfection & sterilization.
Verifies compliance with industry standards (ISO 15858, ASHRAE, FDA, NSF 55, WHO).
Prevents underexposure or overexposure that can affect efficiency & safety.
Optimizes UV distribution in air, water, or surface disinfection systems.

2. Key Parameters for UV Testing
UV Intensity (µW/cm² or mW/cm²) → Measures power at a specific distance.
Wavelength Verification (nm) → Ensures correct UV spectrum (e.g., UVC at 254 nm).
Dosage Calculation (mJ/cm²) → Determines if exposure time meets microbial kill rate.
Uniformity of Coverage (%) → Ensures all areas receive sufficient UV exposure.

3. Recommended UV Dosage Levels for Disinfection
Application
UV Wavelength (nm)
Required UV Dose (mJ/cm²)
Air Disinfection (HVAC, Upper Room UVGI)
254
10 – 100
Surface Sterilization (Hospitals, Cleanrooms)
254
20 – 100
Water Purification (NSF 55, EPA)
254
30 – 186
Food Processing & Packaging
254
20 – 100

4. UV Radiation Test Procedure
a. Equipment Required
UV Radiometer – Measures UV intensity (µW/cm²).
Spectrometer – Verifies UV wavelength.
Dosimeter Strips – Color-changing indicators for UV exposure.
Measurement Grid Plan – Defines sampling locations.
b. Test Steps
Turn on the UV system and allow stabilization.
Measure UV intensity at multiple points using a radiometer.
Check wavelength output to ensure correct UV spectrum.
Calculate total UV dose (mJ/cm²) based on exposure time.
Compare results with required disinfection levels.

5. Pass/Fail Criteria for UV Testing
Pass: UV intensity and dosage meet or exceed required levels.
Fail: Insufficient exposure → Requires lamp replacement, repositioning, or increased exposure time.

6. Corrective Actions for UV System Deficiencies
Replace aging UV lamps (output declines over time).
Adjust lamp positioning to improve coverage uniformity.
Increase exposure duration to achieve the required dose.
Clean lamp surfaces & reflectors to maximize UV efficiency.

7. Applications of UV Radiation Tests
Hospital Disinfection (ORs, Isolation Rooms) → Reduces HAIs.
Cleanroom & Pharmaceutical → Controls airborne & surface contamination.
Water & Wastewater Treatment → Inactivates bacteria & viruses.
Food Processing & Storage → Prevents microbial growth.
Would you like a detailed test protocol or help with dosage calculations?