Killing smog from car fumes

NIK about the elimination of vehicles emitting excess levels of hazardous substances from road traffic

The roadworthiness system does not effectively eliminate vehicles emitting excess fumes from road traffic. Efforts taken by the Police and the Road Transport Inspection in this area were also ineffective: the number of roadside inspections was too small to eliminate cars in poor technical condition from Polish roads. The traffic and road police officers often lacked specialist training in road traffic. Also, the measuring equipment was sporadically used to evaluate the vehicle exhaust pollution.

In line with the data of the Police Headquarters, nearly 3 thousand people died on Polish roads in 2019. At the same time, the 2019 report of the European Environment Agency reveals that over 400 thousand people die prematurely in Europe because of the environment pollution every year, including over 40 thousand deaths in Poland. It means that over 10 times more people die prematurely in Poland due to the air pollution than as a result of road accidents. Long-term exposure to smog substances irritates our lungs which lose their capacity and become weaker (we are more susceptible to angina pectoris, arrhythmia or asthma). As a consequence, we are also more liable to severe course of COVID-19.

In large cities, toxic fumes have a significant impact on the number of premature deaths. The substances in car exhaust are much more harmful than industrial pollutants because they spread in the immediate vicinity of people, in high concentrations and at low heights. In large city centres, where it is hard to ensure smooth road traffic, the impact of transport pollutants on the air quality may be even higher, especially in case of the concentration of nitrogen dioxide (NO₂). Based on the study results this impact in Warsaw and Cracow is estimated at about 75 percent.

In Poland in the past decade, thanks to the EU funds, the air pollution emitted by the industry and the power sector was reduced considerably. It was the case mainly due to the requirements implemented for that sector by the EU legislation. But the key legal solutions to protect the environment are still not in place. They are supposed to limit the use of cars most harmful to the environment and lower the nitrogen oxide pollutions, especially in large cities, near arterial roads.

The growing number of cars on Polish roads does not help reduce the adverse impact of transport on the environment. Ever since Poland accessed the EU, the number of cars used in Poland has more than doubled (13.3 million used imported vehicles have been registered). Since there is no tax policy encouraging the purchase of new cars or the more environment-friendly ones, the vehicles registered in that period are mostly used imported cars. In the long run, an average used passenger car is nearly 15 years old.

A big number of vehicles per inhabitant is representative for Poland (580 vehicles per 1000 inhabitants). This number is twice as big as the ratios e.g. for highly developed countries, such as Germany or Austria (about 300 vehicles per 1000 inhabitants). Additionally, Poland has one of the highest percentage of cars above 10 years of age (about 73%) in the EU and the age of 35% of cars exceeds 20 years. Therefore, an effective roadworthiness system is vital for the air quality improvement.

Age structure of passenger cars in Europe - up to 2 years: 5.16%; from 2 to 5 years: 4.72%; from 5 to 10 years: 16.52%; from 10 to 20 years: 38.41%; above 20 years: 35.19%. Percentage of cars above 10 years of age – Latvia: 77.2%; Poland: 73.6%; Hungary: 69.9%; Estonia: 69.6%; Finland: 64.3%; Cyprus: 64.2%; Portugal: 63.3%; Croatia: 62.7%; Spain: 62.7%; Malta: 59.4%; Slovenia: 51%; Turkey: 51%; Norway: 44.3%; the Netherlands: 41.4%; Germany: 40.1%; Switzerland: 35.5%; Great Britain: 34.8%; Austria: 34.4%; Denmark: 30.9%; Belgium: 28.4%. Source: NIK’s analysis based on Eurostat data

The NIK audits to date have focused on the consequences of the near-ground pollution from home heating stoves and local boiler rooms. But they did not deal with another important reason of poor air quality, i.e. the near-ground pollution from road transport. In this audit NIK looked into measures taken in cities with the most intense traffic, where the daily air pollution levels are often exceeded: in Warsaw, Cracow and Łódź. The audit was to establish if the effective laws, organisational and technical solutions as well as efforts taken by public administration bodies made it possible to effectively eliminate vehicles with excess emission of substances harmful for people and the environment from the road traffic.

Ministry of Infrastructure

The Minister of Infrastructure did not ensure comprehensive solutions in the area of transport policy concerning the exhaust emission control standards to help effectively reduce the road transport pollutions.

Until 2015, the Minister of Infrastructure did not even try to implement solutions to reduce the emission of harmful substances from the road traffic, although s/he knew that the roadworthiness system was ineffective and that some vehicle exhaust components were highly hazardous (among others, four audit reports of NIK, the first one of 2009). The Ministry did not take any efforts in this area, although in February 2014 it was presented with the Strategy (developed by a working group established by the Minister). The Strategy included some proposals of solutions to repair the system of vehicle technical inspections.

The audit findings show that the measures taken by the Minister of Infrastructure were actually limited to discharging the obligation to implement the EU Directive of 2 April 2014 (2014/45/UE) on periodic roadworthiness tests for motor vehicles. The Minister started works with over 1.5-years delay (the deadline passed on 20 May 2017). The draft Act was submitted to the Sejm but in December 2018 it was taken off the agenda. The relevant laws have not been adopted until now. As a result of the Minister’s failure to implement the Directive, there are no modern solutions in terms of the vehicle technical inspections in the Polish legislation that would be adapted to the EU law. In line with the EU Directive, the cars that do not meet the technical conditions defined in the homologation documents are not roadworthy.

According to NIK, as a consequence of the Minister’s inactivity, the vehicles with non-functional or removed elements responsible for exhaust cleaning are still found roadworthy by vehicle diagnostic technicians. The problem is the absence of required legal solutions that would help identify such cars.

The Minister of Infrastructure implemented the EU Directive (2014/47/UE) on technical roadside inspections of 3 April 2014 with delay. The laws essential to implement that Directive should have been published by the EU member states by 20 May 2017 but they entered into force only at the beginning of 2019.  

An explicit example showing that the Minister of Infrastructure should act immediately are the results of the exhaust emission measurements in 2019 in Cracow. Over 60 thousand passenger and delivery cars were checked without the need of stopping them for a roadside inspection. It was found that the following percentage of checked vehicles did not meet specific emission standards: nitrogen oxides – 57%, carbon oxide - 48%, hydrocarbons – 45% and particulates – 40%.  

Excess of limits set in Euro standards identified in checked passenger and delivery cars up to 3.5 tonnes. Number of checked cars: 62798. Number of cars with limit excess – carbon oxide: 30179; nitrogen oxides: 35655; hydrocarbons: 28441; particulate matter: 24878. Source: NIK’s analysis based on the report: “Remote Vehicle Emission Measurements”, Cracow July 2019

The measurements show that the highest excess of particulate matter was reported for older, petrol-driven vehicles (from 62.9% of checked vehicles in Euro 4 emission standard to 70.8% in the Euro 2 emission standard, respectively). The reason is different technical standards binding for car manufacturers a dozen or so years ago.  

The highest limit excesses for nitrogen oxides were confirmed in case of newer, diesel cars, mostly in Euro 5 cars (in 83% of checked cars in that category).

The checks also revealed that diesel cars emit even a dozen or so more hazardous particulates than petrol cars.

Average emission of particulate matter in checked passenger cars. gas oil vs petrol: Euro1: 0.84 vs 0.07 g/kg; Euro2: 0.78 vs 0.06 g/kg; Euro3: 0.59 vs 0.03 g/kg; Euro4: 0.30 vs 0.02 g/kg; Euro5: 0.05 vs 0.02 g/kg; Euro6: 0.02 vs 0.01 g/kg. Source: NIK’s analysis based on the report: “Remote Vehicle Emission Measurements”, Cracow July 2019

Measuring stations in cities

The location and the number of measuring devices is of great importance for correct evaluation of the impact of road transport in large urban agglomerations. As part of the State Environmental Monitoring nearly 300 measuring stations operate within the air quality measuring network. However, only 16 stations are located in the immediate vicinity of streets (they are the so-called traffic pollution monitoring stations). In some of these stations the scope of measurements is limited, e.g. the level of nitrogen oxides (NOx) or particulate matter (PM2.5 and PM10) is not measured.

What is important, in half of the provinces, in none of the cities, the air condition was checked by means of traffic pollution monitoring stations. It needs to be emphasised that such stations are not in place in 25 largest Polish cities, e.g. in Poznań, Gdańsk, Lublin, Białystok, Gdynia. The sequence of launching new stations is quite interesting, as well as the lack of correlation between the location and the city size (and the traffic intensity).

Municipal offices

Measures taken by the presidents of the audited cities as part of their supervision over motor vehicle diagnostic stations were ineffective and thus did not really help eliminate vehicles from the road traffic that did not meet the exhaust emission standards.

In Poland as much as 73% of cars is over 10 years old. That is why, it is so important to effectively supervise the way car technical inspections are carried out by vehicle diagnostic technicians (including the measurement of exhaust emissions).

In the audited municipal offices part of controls of the motor vehicle diagnostic stations were conducted less often than required (only once a year) or their scope was limited. Some of those stations were not controlled for up to three years. Besides, the presidents of Warsaw and Cracow did not meet their obligation to verify, in each supervised station, if the vehicle diagnostic technicians properly performed the vehicle technical inspections. E.g. in Warsaw it was the case in over 60% of the diagnostic stations’ controls.

NIK has noted that district heads failed to properly supervise motor vehicle diagnostic stations. The data collected from 85 local governments show that in every fourth district the controls were not carried out at all or were conducted with lower frequency. The key problem may be that the persons hired in district head offices in towns do not have required qualifications. According to the NIK findings, such persons usually lacked technical education which could result in ignoring technical aspects in the control.

NIK also had reservations about the car technical inspections conducted by vehicle diagnostic technicians. The NIK audit in 2017 showed that more than a half of the audited inspections were conducted improperly, in breach of the effective law. They left out a range of activities defined in the regulations as obligatory or performed them imprecisely. Besides, they used some control and measurement instruments that were not accepted for use. The technicians improperly controlled the emission of harmful exhaust components in nearly 40% of the checked vehicles. Almost half of vehicles from that group passed the roadworthy test, despite the fact that they could pose a threat to the environment. Apart from improper supervision exercised by local government units, this situation may result from the withdrawal (in 2004) of the technicians’ obligation to undergo complementary training programmes every two years.

It is also worth noting that over the years, the limits for Euro standards in the emission of the most hazardous exhaust components have been tightened many times, e.g. for particulates it was 28 times and for nitrogen compounds - 12 times. Nevertheless, no changes have been made to the domestic laws to adapt the car inspection procedures in the motor vehicle diagnostic stations. The problem is that devices reducing the emission of hazardous exhaust components, such as DPF (diesel particulate filters) are commonly removed from vehicles. Unfortunately, in Poland such modifications are not followed by any fines for drivers or car workshop owners. 

Police and Road Transport Inspection

Vehicle roadside inspections conducted by the Police and provincial inspectorates of road transport (PIRT) did not guarantee the elimination of vehicles posing a threat to the environment. Activities in that area were not performed systematically, also not as part of everyday service. In many cases the inspections were carried out by persons without required specialist training in road traffic. The measuring devices owned by the audited Police units were used sporadically to evaluate the exhaust pollution. At the same time, they used the equipment that did not undergo obligatory, periodic calibration.

NIK has indicated the deepening problems with headcount levels both in the Police Traffic Departments and road transport inspectorates. As regards the Police that was particularly the case with the Warsaw Metropolitan Police. In the traffic divisions of the audited police stations (as of 30 June 2019) there were the total of 955 employees (91.5% of allocated FTEs), though, the number of police officers who actually were on duty on the Polish roads totalled 761. Correspondingly, in the audited road transport inspectorates the total number of employees was 198 (91% of allocated FTEs), whereas inspections on the roads were carried out by 86 inspectors. What is particularly worrying is the decreasing number of PIRT inspectors conducting inspections on the roads, especially in view of the huge amount of work to do, e.g. the control of drivers' working hours, transportation documents, axle weights, transport of hazardous goods, animals, technical condition, etc.

The roadside inspections conducted by the Police and road transport inspectorates with the use of measuring devices covered a small number of vehicles driving on Polish roads every day. For instance, in 1H2019 in Warsaw, the police officers carried out inspections of the total of 5140 vehicles, however only every 20th car was checked using specialist measuring equipment. According to the Office of Administration and Citizens' Affairs of the Capital City of Warsaw, there were even more vehicles on the roads of Warsaw: every day, apart from the vehicles driving within the border of Warsaw, there were about 500 thousand more cars coming in and going out of Warsaw.

The nationwide regular SMOG campaign does not improve the situation. Within its framework, as part of one-day actions, over 680 thousand vehicles were checked and nearly 8 thousand cases of excess exhaust emission were detected.

The NIK auditors established that during the SMOG campaign the measuring equipment was used sporadically. Without using such equipment, officers can only check fuel or oil leakage, the exhaust system condition (elevated noise level). Only in extreme cases, due to significant smokiness, irregularities related to the exhaust emission may be identified. In line with the law, though, this is not about measuring the emission of gas pollution or the exhaust smokiness. Even in the course of monthly SMOG actions, as part of which the maximum possible number of traffic and road police officers were sent for patrols, in Warsaw and Łódź only 4-7% inspections were conducted with the use of exhaust gas analysers or smoke meters. It was better in Cracow – such devices were used in about 20% of inspections. It also happened that police officers did not take exhaust gas analysers or smoke meters for SMOG actions or they took but did not use them. Therefore, information about the results of such inspections provided by the Police may lead to wrong conclusions.

The NIK audit findings indicate that the Police need to use more of their measuring devices. They are simply much more effective.

The traffic and road police officers were not properly prepared, particularly in terms of specialist skills. About 65% of officers were trained in exhaust emission measuring devices. It means that every third traffic and road police officer was not trained among others in the following areas: vehicle technical inspection, traffic and road service, road traffic management, speed measurement and recording behaviours of road traffic participants. The specialist training coverage, though, was determined by training limits defined by the Police Headquarters. The NIK audit revealed that in some patrols using the exhaust emission measuring equipment there were persons without required training.

Also framework programmes of specialist and complementary courses for road transport inspectors did not cover the aspect of gaining knowledge or skills essential to correctly conduct measurements and service the control and measurement devices.

Another problem was related to the equipment deficits in the Police. On average only every tenth district/ city police station has one exhaust emission control set – 337 police stations had 34 exhaust gas analysers and 34 smoke meters. At the same time, 16 provincial road transport inspectorates had 14 exhaust gas analysers and 81 smoke meters.

The following irregularities were identified in two police stations (in Łódź and in Warsaw), as well as in each of the audited provincial road transport inspectorates: lack of continuity of required metrological controls, legalisation or calibration of exhaust emission measuring devices, use of measuring devices without valid vehicle worthiness certificate/ checks, as well as the lack of documents confirming obligatory periodic calibration. Those irregularities posed a risk that measuring devices could be non-functional when used and that the results of exhaust emission measurements could be unreliable.

The removal of filters from a vehicle or other elements designed to limit excess emission of hazardous substances is a common practice in Poland (such devices are installed in vehicles to meet more and more stringent EURO standards). It needs to be stressed that the manufacturer of a new car, before bringing it to the market, is obliged under the law to get a homologation certificate. Therefore, it is illegal to remove such devices from registered and roadworthy cars. Nevertheless, none of the audited Police units took action against entities providing such services.


In view of the audit findings NIK has addressed the following recommendations:

To the President of the Council of Ministers:

  • to make sure works are resumed as early as possible on implementing Directive 2014/45/EU of 3 April 2014 on periodic roadworthiness tests for motor vehicles and their trailers and repealing Directive 2009/40/UE.

To the Minister of Infrastructure:

To take measures to implement regulations defining:

  • sanctions against people responsible for commissioning, offering and providing the service of removing devices from a vehicle designed to limit excess emission of hazardous substances;
  • the obligation to subject vehicles to additional technical inspections, confirming their roadworthiness after exceeding specific vehicle age and mileage;
  • the method of measuring exhaust emission in the course of vehicle technical inspections, confirming roadworthiness only in the cases of cars which meet environment protection conditions, defined in the homologation documents;
  • a detailed scope, conditions and the mode of controls of motor vehicle diagnostic stations by bodies supervising those entities, documenting the controls and their results, as well as follow-up procedures;
  • the status of vehicle diagnostic technicians and the principles of hiring them, making sure they can do their work independently;
  • the obligation of vehicle diagnostic technicians to systematically raise their qualifications, e.g. in the form of periodic complementary training programmes ending in a state exam which is the precondition for extending their rights to work as vehicle diagnostic technicians.

To the Commander-in-Chief of the Police and the Chief Inspector of Road Transport:

To take actions to:

  • make sure subordinate entities comply with the calibration principles of measuring devices, used to control the exhaust emission;
  • develop the training system for officers hired in the traffic division of the Police and the road transport inspectors to make sure all employees undergo specialist training programmes in the area of exhaust emission control in the shortest time possible.

To the Commander-in-Chief of the Police:

  • to take actions to increase the number of exhaust emission controls, also as part of everyday service and to use the measuring equipment owned by the Police to a wider extent.

Article informations

Date of creation:
10 December 2020 14:44
Date of publication:
10 December 2020 14:44
Published by:
Marta Połczyńska
Date of last change:
10 December 2020 14:44
Last modified by:
Marta Połczyńska
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