Martinovs, Andris

2021, Andris Martinovs, Mezule, L., Ritvars Rēvalds, Pizica, V., Denisova, V., Skudra, A., Kolčs, Guntis, Edgars Zaicevs, Juhna, T.

Indoor air disinfection has become particularly relevant recently because of the Covid-19 pandemics. A shielded device for air and surface disinfection with UV radiation and ozone has been developed. It contains 28 low intensity (11 W) UV lamps (254 nm) in a specially designed three-dimensional grid to provide a large flow cross-sectional area and long path for the air particles to be irradiated. The device can be used in medical institutions, veterinary clinics, manufacturing plants, public premises, poultry, and livestock farms. It does not generate air-ions and ozone concentrations do not exceed the allowed 8-hour average values. The large number of UV lamps and powerful fans ensure air disinfection in large rooms in a relatively short time (400 m3 h -1 ). Simultaneously, the floor surface under the appliance is disinfected. Disinfection efficiency tests demonstrated 99.9999% reduction for Escherichia coli, Staphylococcus aureus and Pseudomonas phage Φ6 aerosols within a single transfer through the system (10 seconds of treatment). The housing of the device protects from direct UV radiation; therefore, people can be in the room during the operation of the device.

2013, Natalia Sinicina, Andris Skromulis, Martinovs, Andris

Saturation of air ions is essentially important for all living beings, especially for human health. Existing sanitary norms provide that concentration of small ions has to be in range of 400-50000 ions cm-3 and unipolarity coefficient 0.4 ≤ K ≤ 1.0. Many species of indoor plants emit organic volatile compounds and air ions, therefore they could be used for improving the quality of indoor air. The results show that ionization level of indoor air is significantly insufficient and selected species of indoor plants are not able to improve it. They serve rather as supplementary surfaces for ion absorption. Possible interaction between microclimate, ion concentration and indoor plants in different times of the day is analyzed.

2017, Natalija Siņicina, Martinovs, Andris

The plants emit different types of volatile organic compounds (Bio VOC’s) and can improve air quality: they effectively remove organic pollutions and reduce the number of microorganisms in the air by releasing phytoncides. The lack of negative ions in the air can cause deterioration of the health of humans breathing it. At the same time, an air saturated with negative ions can improve the state of health and provide a comfortable environment. In this article, the influence of the plants (Cupressus macrocarpa) on the number of ions is proved, based on a series of experiments performed with applying high-voltage pulses (air ionizer). This work is devoted to the elaboration of the mathematical relationship between the air ions concentration and the factors influencing it. For this purpose an experimental stand was made, consisting of two equal compartments: one contained the plants while another one was used as a control without plants. It was concluded that the plants, in general, are able to stabilize the ion concentration and to reduce its fluctuations. The plants help to increase the concentration of negative ions and to decrease the concentration of positive ones.

2015, Natālija Siņicina, Andris Skromulis, Martinovs, Andris

Literature sources and earlier researches state that plants may be able to produce a variety of air ions, including negative light ions. In this article, the regularity of influence of plants on the number of ions in the room is being proved, basing on a series of experiments performed with the following plants: Spathiphyllum, Scindapsus, Strobilanthes, Chlorophytum and Pinus mugo. It was concluded that plants, in general, are able to stabilize the indoor ion concentration and reduce its fluctuations. The plants help to increase the concentrations of negative ions and decrease the concentration of positive ones, however the optimal and “healthy” ion concentration was not reached. Plants without artificial illumination work more as ion reducers, not producers.</span></p>