DELTAOHM - Model LP UVIndex.02 - UV index radiometer
The radiometer LP UVI 02.P, measures the global effective irradiance on a flat surface (Watt / m2 effective), according to the requirements of the WMO for the measurement of UV-index. The global irradiance is the sum of direct sun and of diffuse irradiance. In the ultraviolet spectral region, unlike what occurs in the portion of the visible light where the direct component is prevalent on the diffuse component, the light is strongly scattered in the atmosphere, and then the two components are equal; it is therefore of primary importance that the tool is able to accurately measure both components.
The radiometer LP UVI 02.P is produced in the version with current output and voltage output:
LP UVI 02.P AC is a current loop transmitter (4÷20mA) with measuring range 0÷16 UV-index,
LP UVI 02.P1 AC is a current loop transmitter (4÷20mA) with measuring range 0÷20 UV-index,
LP UVI 02.P AV is a voltage loop transmitter with measuring range 0÷16 UV-index; the output, dependingon the version, is: 0-1V, 0-5V 0-10V.
LP UVI 02.P1 AV is a voltage loop transmitter with measuring range 0÷20 UV-index; the output, dependingon the version, is: 0-1V, 0-5V 0-10V.
The versions 02.1 have a full scale that reach 20 UV-index and are suitable for the measurement of UV in equatorial areas and high mountain; as demonstrated by recent studies, in these places index value UV of 11 can be exceeded for a significant time.
The power supplied is required at 8-30 Vdc, except for the version LP UVI 02.P AV10 (voltage output 0-10 V) which is of 15-30 Vdc.
The instrument is managed to operate for long periods without maintenance (except cleaning of the dome and checking the status of silica gel) provided that it is properly powered. This feature makes the device ideal for use in remote weather stations also.
The radiometer can also be used for monitoring of UV solar. Today, many services that provide weather data include the UV index in the available data. The data are used to determine the degree of protection required for the sunlight does not cause damage to the skin and then to human health.
L’UV_index in accordance with the requirements of WMO is calculated from total Effective Irradiance Eeff W/m2 using the following formula:
UV_index= Eeff [W/m2 ] x 40 [UV_index]/[W/m2 ]
The UV-index scale indicates the potential damage that the solar ultraviolet radiation causes the skin and the eyes. The higher the value of UV-index the greater the likelihood of damage. Improve knowledge of the UV means improving the prevention of skin diseases; in fact, correct information of this index allows to take adequate measures.
In Figure 1.1 shows the values of the UV index and the category of exposure
The World Health Organization, according to the index measured, prescribes a series of protective measures to be taken to minimize the damage caused by ultraviolet rays - Figure 1.2.:
In recent years, aided by the ozone hole, the attention given by the World Health Organization (http://www.who.int/uv/intersunprogramme/activities/uv_index/en/) to the problem of exposure to ultraviolet radiation is increasing, as evidenced by the number of scientific articles grow regarding this topic.