The range of usable UVB for reptiles is between 290-335 nm. The VivTeh SurSun UV Meter has a peak range of 300 nm. When you are reading your UV Meter, you are reading the power density of the UVB in uW/cm2. The higher the number, the more intense the UVB is in that particular spot. The number will lower the further away from the bulb, and the more leaves, tank covers, etc that filter the light. YES, a screened tank cover can significantly impact the amount of UV that gets through to your animal. That is why it is important that you have a UV Meter, to make sure the animal is getting what it needs.
To assure accuracy, the sensor at the top is a silicon carbide photodiode in UV glass with a metal oxide coating to block UVA from altering the UVB readings.
- 1. Turn the UVB light on for 5 minutes.
- 2. Place the sensor at the level of the basking site facing straight up toward the UV light or at 12”.
- 3. Press and hold the button on the front of the meter.
- 4. Note the reading on the LCD screen in your tracking log.
Keeping the distance and location of your measurements the same each time you measure is important.
Remember, it is CRUCIAL to replace your UV bulbs, no matter the brand, once they lose 30% of their original output. Ideally you want to use a brand new bulb to measure against.
When using this meter to compare different types of UV bulbs ,the readings should be considered relative rather than absolute due to the difference in spectral distribution.
ALL UVB meters need to be calibrated roughly once a year. VivTech offers this service for a nominal fee, see our online shop for details.
Different UVB meters from different companies and even models from the same company may read very different than others due to different responses in UV lengths, peak range, and/or calibration.