The domestic status quo of ultraviolet radiation illuminance meter UV energy meter

The domestic status quo of ultraviolet radiation illuminance meter UV energy meter

1. China's ultraviolet radiation illuminance standard The ultraviolet radiation illuminance meter is often referred to as the UV energy meter. With the development of economy, ultraviolet radiation illuminance meter (UV energy meter) is used more and more in industry, and the traceability of ultraviolet radiation illuminance meter becomes more and more important. The international division of UV bands is not uniform. At present, the division of ultraviolet radiation bands in China is divided into four bands: A1, A2, B, and C.


The ultraviolet light sources corresponding to the above four wavelength bands include high-pressure mercury lamps, black-light type high-pressure mercury lamps, and low-pressure mercury lamps. The working standard of China's ultraviolet radiation illuminance is mainly composed of a spectroradiometer, a standard ultraviolet radiation illuminance meter, various ultraviolet light sources, etc., which are used to store and reproduce the ultraviolet radiation measurement values. However, because the above standards were built in 1989, they can no longer fully meet the traceability requirements of the modern market for UV radiation meters. With the gradual introduction of such instruments abroad, the calibration of UV irradiance meters has emerged with the coexistence of multiple national standards, which has caused problems for the majority of users of UV irradiance meters.

2. The market where multi-national standards coexist At present, the domestic market share of the irradiance meters produced by the three countries of the United States, Germany, and Japan is still quite large. Relatively speaking, the instruments are also good, with good stability and long service life. But there is a big problem. Even the standards of the same country cannot be completely unified. For example, the American standard, UV irradiance is traceable to NIST, but it has produced different measurement results. The two most typical manufacturers of irradiance meters, EIT and International Light, also use A-band instruments to verify with national standards. The indication error of EIT is 30% ~ 70%, while the indication error of International Light can be Control within 10%, which is basically consistent with national standards. The instruments in Germany and Japan also have the same problem. There are instruments that are consistent with national standards and instruments that have far-distance measurement results. For example, two instruments with different models from the same manufacturer in Germany have the same measurement band, but the measured results are very different. This may be caused by the inconsistent spectral response of the calibration light source or instrument detector. In short, there is no unified standard for ultraviolet irradiance in the world to restrict manufacturers. This has caused the situation of multi-national standards coexisting, which also makes it difficult to measure ultraviolet irradiance. Here it is necessary to talk about China's UV irradiance standards in the international comparison.

In December 2002, the Chinese Academy of Metrological Sciences (NIM) participated in the first international “APMP ​​PR-S1 International Comparison of Illuminance Response of UVA Detectors” organized by the Asia-Pacific Metrology Planning Organization (APMP). The comparison results show that: in the seven participating laboratories, the magnitude of NIM is the closest to the international reference value, and the deviation of the UV365 illumination response of the narrow band UVA and the UVA illumination response of the wide band is -0.57% respectively from the international reference value ( k = 2) and -0.53% (k = 2). Under certain conditions, the uncertainty of the recurrence of the magnitude of ultraviolet radiation in the broad band has also been improved from the original 10% (k = 1) to 2.0% (k = 1). It should be said that China's existing UV radiation illuminance standards are trustworthy.


Third, the ultraviolet radiation illuminance meter UV energy meter measurement domestic status quo response and solution for this more chaotic situation, the best solution is no unified standard. As far as the ultraviolet irradiance meter used in industrial production is currently used, it is mostly used in ultraviolet curing and ultraviolet exposure to measure the irradiance or energy of the UV furnace or UV lamp tube, and the band is in UVA and UVB, which is used to measure the ultraviolet radiation energy There are more instruments, commonly known as UV energy meter.

For use and calibration, we recommend:

1. The same company uses instruments of the same manufacturer and model as much as possible, so as to facilitate the uniformity of values ​​and facilitate internal company records and comparisons. When using different types of illuminance meters from the same company for measurement, the measurement results may also be quite different.
2. The irradiance of industrial UV lamps is not very stable and uneven. It is best to measure several times during the measurement. It usually takes a period of time for the UV lamp to turn on before the light emission condition stabilizes.
3. For many instruments used to measure the curing energy, many cases only care about one reading. For example, based on production experience, with an instrument measuring 1000mJ / cm2 energy, the curing is good. Maybe this instrument is very different from the national standard, but you As long as you know that this instrument measures 1000mJ / cm2, it is normal. At this time, you only need to pay attention to the annual rate of change of the instrument, or add a correction factor to the instrument according to the data given in the calibration certificate, and record a reading after correction.
4. Not all instruments can be calibrated according to the existing national standards, so when the instrument is detected with a large measurement error, confirm whether the measurement band of the instrument is consistent with the national standard, if it is inconsistent, or send it back to the original The factory inspection shall be used according to the reference after correction according to the calibration certificate.
5. Due to the special nature of the detector materials used in the UV irradiance meter, the annual rate of change is still relatively large (especially domestic instruments, foreign instruments are relatively good), coupled with frequent use, it is easy to produce quantity drift, If there is doubt about the value, it is better to send it to the inspection in time.
6. Pay attention to the service life of the ultraviolet irradiance meter, especially for the ultraviolet irradiance meter close to the service life or overdue, it should be used by reference.
7. For some special radiometers, measuring a large range (such as W or J level), special band (such as UVV band visible light radiation), there is no verification procedure, and can be sent to the original factory, the National Institute of Metrology, etc. calibration. Finally, let's briefly talk about C-band instruments. These instruments are mainly used in the medical field. Because short-wavelength ultraviolet rays have sterilization and disinfection effects, the measurement range is relatively small. Most of these instruments are domestically produced and have a high degree of consistency with the national standard.