BS ISO 15727:2020 pdf free.UV-C devices —Measurement ofthe output of a UV-C lamp.
This document specifies the measurement of the output of a Uv-C lamp, types of Uv-c lamp, lampballast, and safety issues.
lt is applicable to the output measurement of linear Uv-C disinfection lamps.
This document specifies a measurement method for evaluating output power of Uv-C lamps installedin heating, ventilation and air conditioning (HVAC) systems. The method includes the simulationmeasurement of Uv-C output power of Uv-c lamps under various temperatures and various airvelocities,and under conditions that the axial direction of the lamp is parallel or perpendicular tothe air flow direction. It can reliably evaluate and compare the Uv-C output power of Uv-C lamps inthe ultraviolet germicidal irradiation (UVGI) device based on the testing results. lf the microbialinactivation rate of a particular UVGl device equipped with the same type of Uv-cC lamp is known, themicrobial inactivation rate of the UVGl device at various temperatures and at various air velocities canbe evaluated.The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references, only the edition cited applies.Forundated references, the latest edition of the referenced document (including any amendments) applies.Magnetic ballasts are used to start the Uv-C lamp and may be either standard electromagnetic orenergy-efficient electromagnetic. The ballast provides a time-delayed inductive kick with enoughvoltage to ionize the gas mixture in the tube after which the current through the tube keeps thefilaments energized.The starter will cycle until the tube lights up. While the Uv-C lamp is on, a preheatballast is just an inductor which at the main frequency (50Hz or 60 Hz) has the appropriate impedanceto limit the current to the Uv-C lamp to the proper value.Ballasts shall be fairly closely matched to theUV-C lamp in terms of tube wattage, length, and diameter.
Electronic ballasts are basically switching power supplies,which eliminate the large,heavy, ‘iron’ballast in favour of an integrated high frequency inverter/switcher.Current limiting is then done by avery small inductor, which has sufficient impedance at the high frequency.Properly designed electronicballasts are relatively reliable,which depend on the ambient operating temperature, location withrespect to the heat produced by the Uv-C lamp as well as other factors.
There are two methods to measure the output of a Uv-C lamp:Measurement of the output of a UV-Clamp in a darkroom: Tests in laboratory (also known as static darkroom test) are conducted to ensure the accuracy and consistency of the measured results;2. Measurement of the output of a Uv-C lamp in a test chamber: For industrial application, the tests in a test chamber shall take account of the impact of environmental changes in field (such astemperature change and air velocity change).This method is described in Annex B.
The cosine correction for radiometers and spectroradiometers is critical to the proper measurement ofthe Uv-C irradiance.The cosine correction shall be confirmed by the following method for each Uv-Clamp and ballast combination so that the Uv-C lamp measurements are consistent within and betweenlaboratories.The minimum measurement distance needs to be determined for the given Uv-C lamp and Uv-Cradiometer in order to verify cosine response characteristics of the Uv-c radiometer and reduce itscosine correction error. The method is as follows:
a) Take readings of the Uv-C radiometer for different distances (radiometer position perpendicular to the UV-C lamp axis), see Figure 4;
b) Take several readings of the Uv-C irradiance.For example, moving the radiometer from the closest point to the most remote point and then back again;BS ISO 15727 pdf download.