The cost-effective Particulate Matter (PM) monitor prototype developed by Additess LTD and the Cyprus Institute (CyI), under the framework of PRECEPT project will be extensively tested in the environmental chamber of the Instrumentation laboratory of CyI. The performance of the PRECEPT PM monitor will be evaluated with aerosols of standard sizes and compared with that of a laboratory grade instrument. In addition, the prototype will be subjected to temperature and pressure conditions that will be encountered during observational flights conducted with Unmanned Aerial Vehicles (UAVs).