Indoor air quality in museums and historical buildings in St Petersburg and in north-west region of Russia.

This presentation deals with the problem of achieving stable microclimate in old buildings ofSt Petersburg - such as churches, museums and palaces. Characteristic traits of such buildingsare rather thick envelops which as a rule accumulate large quantities of heat or cold. Themajority of these buildings are equipped only with central water heating and are naturallyventilated.Experimental study of microclimate in buildings of this kind proves that during cold season(with average temperature -10C) the relative humidity there will be about 30-35% and less. Insummer time temperature background does not rise above 22-24C whereas the relativehumidity sometimes can rise up to 75-80%. Eventually we should like to note that climateparameters of St Petersburg can be taken as a characteristic for entire Norten-West of Russia.Inserting into such buildings air conditioning systems (provided with cooling plants and devicesfor automatic control) does not always give positive results. With consideration of climatefeatures of the region and peculiarities of the buildings we worked out system which helps tomaintain stable microclimate, special attention to thermal inertia of walls included. Thisdecision will give an opportunity to reduce a load on heating system at any rate to 15-20%. Itwill also give the chance for adiabatic humidity control in winter which is nessessary for thehumidity control. Besides, it will secure periodical air cooling (with dehumidification andnatural cooling accumulators if nessessary).Analysis proves this decision to be sufficiently reliable for the purposes of keepingmicroclimate parameters. Primary price of the system is about 1,5 times lower than of full airconditioning. Besides, this system while in operation, will give about 30 percent economy ofenergy resourses. Today such system works in the Russian Museum.