Heating tobacco instead of burning offers a potentially lower risk of delivering nicotine compared to conventional cigarettes. The majority of heat-not-burnt tobacco product studies have been related to the mainstream aerosol, but the data on the second hand aerosol is yet limited to several chamber studies, impact on indoor air quality in real life settings has not been yet reported. Here we assess pollution generated by tobacco heating system in a hospitality venue. Volunteers used tobacco heating system in a night club during non-operation hours. Additionally, indoor air quality was assessed while club in operation. Real-time aerosol particle concentration and off-line carbonyl, nicotine and 3-ethenylpyridine concentration was measured. Observed levels of particle number concentration was as follows: background at 1E+4 # cm-3, 10 users at 5E+4 # cm-3, 30 users at 1E+5 # cm-3 and club in operation at 1E+6 # cm-3 – 1E+7 # cm-3. This represents an increase by an order of magnitude in each subsequent scenario. The club featured relatively high background concentrations of gaseous pollutants presumably due to the third hand smoke. The impact of the usage of THS in non-operating club to the gaseous pollutant variation was much lower if at all significant compared to particle concentrations. The usage of tobacco heating system resulted in increasing particle number and mass concentrations from the background by an order of magnitude, but yet were an order of magnitude lower compared to club in operation. The majority of gaseous pollutant concentration were not affected, except nicotine.