The irradiation intensity of ultraviolet lamp beads (UV lamps) in water is affected by a number of factors. These factors can be broadly categorized into the characteristics of the lamp beads themselves, the nature of the water body and the configuration of the system and other aspects. Specifically, including but not limited to the following: 

1. Lamp bead power: generally speaking, the higher the power of the lamp bead, the higher the intensity of the UV radiation produced. 

2. Lamp bead type: different types of UV lamp beads (e.g., low-pressure mercury lamps, medium-pressure mercury lamps, LED UV lamps, etc.) have different output characteristics and efficiencies.

3. Use time: UV lamp beads with the use of time increases, its output intensity may gradually decline. 

4. Temperature: ambient temperature and lamp bead working temperature will affect the efficiency of the lamp beads. 

5. Water quality: suspended solids, turbidity, color and mineral content in the water will affect the penetration ability of UV light, which in turn affects the disinfection effect. 

6. Water speed: water flow too fast may lead to the water body in the UV lamp under the residence time is not enough, thus reducing the disinfection effect; water flow is too slow may increase energy consumption.

7. Lamp cleanliness: The cleanliness of the lamp surface directly affects the UV transmittance. 

8. Distance between the lamp and the water: UV intensity with the increase in distance and attenuation, so the distance between the lamp and the treated water is also an important factor. 

9. System design: the layout and design of the entire UV disinfection system will also affect the effective use of ultraviolet light.