Occupational exposure to diesel engine emissions represents one of the main risk factors for the health of workers employed in numerous industrial, logistics, extractive and construction sectors. In recent years, European institutions have strengthened the regulatory framework aimed at protecting health and safety in the workplace through the adoption of specific provisions dedicated to carcinogenic and mutagenic agents. In this context, Directive (EU) 2019/130 is introduced, which has brought important updates to European legislation concerning occupational exposure to hazardous agents, expressly including diesel engine exhaust emissions among the carcinogenic agents to be monitored and controlled, and it now represents the main European regulatory reference regarding EU diesel emission limits.
The introduction of specific occupational exposure limits requires companies to adopt increasingly accurate assessment and monitoring procedures, aimed at ensuring regulatory compliance and the protection of workers. The sectors most affected include industrial, logistics, port, mining and construction activities, as well as all contexts in which diesel-powered vehicles and machinery are used in enclosed or poorly ventilated environments.
This article examines the following:
- the regulatory limits introduced by EU Directive 2019/130 and EU Directive 2019/983 and their transposition into Italy;
- how exposure to diesel engine exhaust gases is assessed;
- the monitoring systems and sampling techniques required;
- the NIOSH 5040 analytical method for the determination of Elemental Carbon (EC);
- the practical implications for employers.
What is EU Directive 2019/130?
Directive (UE) 2019/130 of the European Parliament and of the Council entered into force on 20 February 2019 and represents one of the main updates to European legislation dedicated to the protection of workers against risks arising from exposure to carcinogenic or mutagenic agents during work activities. The measure amends Directive 2004/37/CE by introducing new occupational exposure limit values for several hazardous substances and expanding the level of protection for exposed workers.
Sectors concerned
The regulation applies to all sectors in which these emissions may be present to a significant extent, in particular:
- industrial activities;
- construction sites;
- goods handling and logistics;
- port activities;
- mines and tunnels.
Transposition in Italy
In Italy the directive was transposed through the Interministerial Decree of 11 February 2021 “Amendments to Annexes XLII and XLIII to Legislative Decree 81/2008. Implementation of Directive (EU) 2019/130 and Directive (EU) 2019/983”. The measure amended the annexes to the Consolidated Act on Safety by formally introducing diesel engine emissions among carcinogenic agents subject to monitoring.
About occupational exposure limits, the decree establishes an Occupational Exposure Limit Value (OEL) expressed as a concentration of Elemental Carbon (EC) is set at 0.05 mg/m³. This limit value applies starting from 21 February 2023. For underground mining activities and tunnel construction, a longer transitional period has been established, with application of the limit starting from 21 February 2026, considering the greater technical complexity of the interventions required to adapt working environments.
| Scope of application | OEL Elemental Carbon (EC) | Effective date |
|---|---|---|
| All sectors | 0.05 mg/m³ (8-hour weighted average) | 21 February 2023 |
| Underground mining and tunnel construction | 0.05 mg/m³ (8-hour weighted average) | 21 February 2026 |
Assessment of exposure to diesel engine exhaust gases
The assessment of occupational exposure to diesel emissions represents today a fundamental element of the prevention activities required by European legislation. Diesel exhaust gases are in fact composed of a complex mixture of gaseous substances and fine particulate matter that can have significant effects on human health.
The most regulated pollutants
- Nitrogen oxides (NOx): mainly composed of nitric oxide and nitrogen dioxide, contribute to irritative and respiratory effects.
- Particulate matter (PM): solid and liquid particles of very small size, associated with chronic effects on the respiratory and cardiovascular system and an increased carcinogenic risk.
European regulations on vehicle emissions, such as Euro 6 standards, have progressively reduced exhaust emissions from new diesel engines through increasingly stringent limits for NOx and particulate matter. However, these regulations mainly concern vehicle type approval and not the assessment of occupational exposure in workplaces. EU Directive 2019/130 instead introduces a specific approach oriented towards worker protection, establishing occupational exposure limit values and environmental monitoring obligations.
Elemental Carbon as a reference marker
For the assessment of occupational exposure, the reference marker identified by European legislation is Elemental Carbon (EC), a stable component of diesel particulate matter that represents a reliable indicator of the presence of diesel engine emissions in the workplace.
The OEL established by the regulation is equal to 0.05 mg/m³ of Elemental Carbon, measured as an 8-hour time weighted average. This value represents the reference for compliance assessment and for the adoption of prevention and protection measures.
Required monitoring systems
Compliance with the limits set by EU Directive 2019/130 requires the implementation of adequate environmental monitoring systems in workplaces. The assessment process must be designed to provide representative data of the actual exposure of workers during normal operational activities.
Sampling is generally performed using personal devices or fixed stations capable of collecting airborne particulate present in the work environment. The execution methods must comply with the main technical reference standards. The application of these standards makes it possible to obtain reliable and comparable results, essential for correct risk assessment and for the implementation of prevention measures required by the regulation.
Challenges in sampling Elemental Carbon
Il campionamento dell’EC presenta alcune criticità tecniche che possono influenzare la Sampling EC presents several technical challenges that can influence the representativeness of the sample and require careful design of the monitoring strategy:
- the presence of other sources of carbonaceous particulate;
- environmental interferences;
- variable operating conditions.
This sensitive issue has been addressed by PM_TEN within the framework of the CALIPSO project. For this reason, it is essential to rely on specialised laboratories and validated analytical methodologies.
PM_TEN offers specific environmental monitoring and analysis services dedicated to the assessment of exposure to diesel emissions, including the determination of Elemental Carbon (EC). Further information is available in the section dedicated to environmental monitoring services.
NIOSH 5040 Method
For the determination of Elemental Carbon and Organic Carbon in diesel emissions, the most widespread and internationally recognized analytical method is the NIOSH 5040 Method. The procedure involves sampling airborne particulate using quartz filters and subsequent laboratory analysis through a thermo-optical technique that allows distinguishing and quantifying the fractions of Organic Carbon (OC) and Elemental Carbon (EC).
Operational advantages of the method
- High selectivity toward diesel emissions, with reduction of interferences due to other sources of particulate present in the work environment.
- Accurate and reproducible results even in contexts characterized by low concentrations of contaminant.
- High analytical sensitivity, with limits of quantification that, under appropriate sampling conditions, are compatible with the limit values introduced by EU Directive 2019/130.
Implications of EU Directive 2019/130
The introduction of EU Directive 2019/130 and its national transposition represents an important step forward in protecting the health of workers exposed to diesel engine emissions. Companies are required to strengthen risk assessment processes, adopt monitoring systems compliant with technical standards and implement effective prevention and control measures.
For employers, this means ensuring compliance with occupational exposure limit values, adequately documenting monitoring activities and periodically updating risk assessments. At the same time, control authorities now have clearer regulatory references and uniform criteria for verifying company compliance.
The application of EU Directive 2019/130 and EU Directive 2019/983 therefore requires an integrated approach that includes compliance with diesel emission limits, the adoption of monitoring programs and the use of reliable analytical methodologies for determining Elemental Carbon.
