Database of the Annual Processing and Air Quality Information System

The periodically published Tabular Survey is a result of the processing of air pollution data that is systematically stored over the calendar year in the air pollution database from all significant networks monitoring air pollution in the country. From the table Air pollution monitoring sites based on the owner and location in the administrative region of the Czech Republic - 2002 it is apparent from how many monitoring (active) stations of the overall number of the stations data were stored and processed.

Since 1992, the current information technology has been utilized to prepare and further develop the Air Quality Information System (ISKO). The restructured Air Pollution Information System (IIS) has become its integral component, along with other information sources for evaluating air quality.

The Air Quality Information System collects and generally provides access to data gathered within significant air pollution monitoring networks. It thus allows more effective general utilization of this expensive data. The integrated regionalised evaluation of air pollution levels, and analysis of the development over time of the status of air pollution in this country would not be feasible without collecting and archiving systematically at one place all the air pollution data available. The continuous need to make this assessment objective also necessitates simultaneous accessibility of emission, meteorological and climatic data and geographic information on the locations of pollution sources, the extent and location of forest growth, residential areas, roadways and similar information.

Fig. 1 schematically depicts ISKO�s links to data sources and co-operating systems. The scheme outlines the interconnection of air quality monitoring networks and sources of data on emissions with data processing and information layers represented by ISKO, and the linkage to a higher-level layer - "cross-sectional" information systems. The actual interconnection is carried out through exchange of data on magnetic media, over switched data lines and, in case of data from the AIM network, also over fixed circuits of the CHMI�s private data network.

Computer System

Since 1993, both the Tabular Survey and the Graphic Yearbook have been completely prepared on a computer system. It consists of a computer network around an SUN ENTERPRISE 450 database server with the installed Ingres multi-user relative database system under the SOLARIS operating system. The data core of the information system is implemented under RDBMS Ingres with predominant utilization of client-server architecture. The concept of the system is based on distributed processing in the local network at Sun SPARC working stations and personal computers with direct access of processing and analytical programs, such as the ARC/INFO geographical information system on Sun ULTRA, the statistical programs SPSS, Systat, tabular and graphical programs, to the data in the central database on SUN ENTERPRISE 450 with features of uninterrupted and backed-up operation.

The Czech Hydrometeorological Institute has its regional offices in all the former regional capitals, which are mainly concerned with measurements, data collection and initial processing within their respective regions. The offices are connected to the central system in Prague via CHMI�s private data network. This Institute�s organizational structure and current technical facilities, as well as a growing need to ensure that the regional offices and cooperating organizations can manage a matching scope of data processing and utilization for their areas, indicate the need for a gradual transition to some form of a more thoroughly allocated concept of the entire air quality information system.

Air pollution assesment

In 2002 a new Clean Air Act No. 86/2002 Coll. and the Regulation of the Government of the Czech Republic No. 350/2002 Coll. setting the air pollution limit values and methods of air quality assessment came into force. The new legislation fully reflects the requirements of the European Union. The following tables show the limit values and margins of tolerance set by the above Regulation.

For the assessment of data for the year 2002 margins of tolerance for SO₂, NO₂, PM10 and Pb are determined on the basis of First Daughter Directive (1999/30/EC). Margins of tolerance of other assessed substances correspond to the values specified by the Regulation of the Government on air pollution limit values.

The limit values for the protection of health, vegetation and ecosystems pursuant to the Regulation of the Government setting the air pollution limit values, conditions and the way of air quality monitoring, assessment, evaluation and management and implementation of air protection regulation measures, and setting the accessible level of odor nuisance and the volume of and access to information on air quality.

Limit values for health protection
Pollutant	Averaging Interval	Limit value	Margin of tolerance (for year 2002)	Maximum tolerated number of exceedences per calendar years
SO₂	calendar year	50 μg.m^-3	without margin of tolerance	0
	24 hours	125 μg.m^-3	without margin of tolerance	3
	1 hour	350 μg.m^-3	90 μg.m^-3	24
NO₂	calendar year	40 μg.m^-3	16 μg.m^-3	0
NO₂	1 hour	200 μg.m^-3	80 μg.m^-3	18
PM₁₀	calendar year	40 μg.m^-3	4.8 μg.m^-3	0
PM₁₀	24 hours	50 μg.m^-3	15 μg.m^-3	35
CO	max. daily 8-h moving average	10 000 μg.m^-3	6 000 μg.m^-3	0
benzene	calendar year	5 μg.m^-3	5 μg.m^-3	0
O₃	max. daily 8-h moving average	120 μg.m^-3	without margin of tolerance	25, 3-year average
Pb	calendar year	0.5 μg.m^-3	0.3 μg.m^-3	0
Cd	calendar year	0.005 μg.m^-3	0.003 μg.m^-3	0
NH₃	calendar year	100 μg.m^-3	60 μg.m^-3	0
As	calendar year	0.006 μg.m^-3	0.006 μg.m^-3	0
Ni	calendar year	0.02 μg.m^-3	0.016 μg.m^-3	0
Benzo(a)pyrene	calendar year	0.05 μg.m^-3	without margin of tolerance	0
benzen	calendar year	0.001 μg.m^-3	0.008 μg.m^-3	0
Deposition - deposition limit value	month	12.5 μg.m^-3	without margin of tolerance	0

Legenda
¹	The margin of tolerance is the per cent of air pollution limit or a part of its absolute value, by which the limit value may be exceeded. This value is reduced regularly in subsequent years until it reaches zero value.

Limit values for the protection of ecosystems
Pollutant	Averaging interval	Limit value	Margin of tolerance¹⁾	Maximum tolerated number of exceedances per calendar year
SO₂	Calendar year and winter period (1.10.-31.3.)	20 μg.m^-3	without margin of tolerance	0
NO_x	calendar year	30 μg.m^-3	without margin of tolerance	0
O₃	AOT40²⁾, calculated from 1h values between May and July, 5-year average	18 000 μg.m^-3.h	without margin of tolerance	0

Legenda
¹	The margin of tolerance is the per cent of air pollution limit or a part of its absolute value, by which the limit value may be exceeded. This value is reduced regularly in subsequent years until it reaches zero value.
²	AOT40 is the sum of differences between hourly concentrations higher than the threshold concentration 80 μg·m^-3 (40 ppb) and the value 80 μg·m^-3, in the period from 8 a.m. to 8 p.m. CET.

In order to enable the comparison with air quality assessment in previous years, in addition to air pollution characteristics required by the new legislation also air pollution characteristics introduced by the Decree of the Federal Committee for the Environment of October 1, 1991, attached to Act. No. 309/91 Coll., the Clean Air Act, in the wording of Act No. 211/94 Coll., which are not covered too strictly by the new legislation (air pollution limit values for SPM, NOx and CO), or air pollution limit values set up by the above Decree, in which exceedences were reported. (The table has been copied over from the above Decree, with some formal modifications.)

Separate overviews of exceedences of limit values required by the new legislation and selected air pollution characteristics specified by the Decree of the Federal Committee for the Environment are presented (starting with the worst stations).

Limit values - Decree of the Federal Committee for the Environment
Pollutant	Expressed as	Limit values [μg.m^-3]
Pollutant	Expressed as	IH_r	IH_d	IH_8h	IH_k	General requirement**
Suspended particulate matter	SPM	60	150		500	IH_d and IH_k must not be exceeded in more than 5% of measurements annually.
Sulphur dioxide	SO₂	60	150		500
Sulphur dioxide and suspended particulate matter	SO₂ + SPM		250*
Nitrogen oxides	NO₂	80	100		200	IH_d and IH_k must not be exceeded in more than 5% of measurements annually.
Carbon monoxide	CO		5000		10 000
Ozone	O₃			160
Lead in suspended particulate matter	Pb	0.5
Cadmium in suspended particulate matter	Cd	0.01

Legends
*	Calculated as the arithmetic sum of average daily concentrations of the two components
**	i.e. the 95th percentiles of daily concentrations must not exceed IHd and the 95th percentiles of the half-hour concentrations must not exceed IH_k
IH_r	average annual pollutant concentration. Average concentration is understood to be the mean value of concentration, determined at a given site over a time period of one year as the arithmetic mean of average 24-hour concentrations
IH_d	average daily pollutant concentration. Average concentration is understood to be the mean value of concentration, determined at a given site over a time period of 24 hours. Average daily concentration is also understood to be the mean value of at least twelve evenly distributed measurements of average half-hour concentrations over a time period of 24 hours (arithmetic mean)
IH_8h	average eight-hour pollutant concentration. Average eight-hour concentration is understood to be the mean value of concentration, as determined at a given site over a time period of eight hours
IH_k	average half-hour pollutant concentration. Average half-hour concentration is understood to be the mean value of concentration as determined at a given site over a time period of 30 minutes

Computer System

Air pollution assesment

*

**

IHr

IHd

IH8h

IHk

IH_r

IH_d

IH_8h

IH_k