04 & 05 November 2025
Halls 1, 2, 4 & 6, IFEMA, Madrid
05 & 06 November 2025
Halls 8 & 10, IFEMA, Madrid
04 & 05 November 2025
Halls 1, 2, 4 & 6, IFEMA, Madrid
05 & 06 November 2025
Halls 8 & 10, IFEMA, Madrid
Does the coronavirus affect air purification technology? This is a question safety officials are currently asking: Does a general ventilation system in metal processing companies make viruses more likely to spread in production? The high filter efficiencies and quality of the integrated filters indicate otherwise.
The coronavirus (COVID-19) is spreading worldwide. At the same time, safety concerns in companies are increasing. The metalworking industry is also affected. Here, there are often spacious production halls that allow for maintaining the two-meter distancing regulations recommended by renowned virologists. However, to provide comprehensive protection for production employees, safety managers are also studying other health risks.
Air purification technology is also under scrutiny in the wake of the current health crisis. And for the following reason: safety officials fear that systems that are actually meant to protect employees could actually have the opposite effect in the current situation, i.e., a virus spread. This line of thinking applies exclusively to systems that allow air recirculation. This mode of operation is carried out in three steps:
1. Contaminated air is extracted during welding or cutting.
2. After detecting hazardous substances, high-performance filters in the systems separate the particles.
3. Air purification systems return clean air to the workshop.
This is especially true for general ventilation systems, which include:
– Filter towers as independent general ventilation according to the layered ventilation principle
– Push-pull systems
– General ventilation systems with displacement ventilation
– General ventilation systems with mixed ventilation, also as an independent variant
Safety officials are wondering whether coronaviruses are captured even by filter media due to their size and whether they are further distributed in the general ventilation system when the clean air is discharged. Wouldn’t it be better for companies not to turn on the systems during the corona crisis?
Based on the knowledge gained so far about the coronavirus, however, there is currently no basis for these fears. The reason for this is the filter systems commonly used today. As a rule, they feature high-quality filters and a high filter efficiency to separate even ultrafine particles. Welding smoke particles and particles from the corona virus family are in the same order of magnitude. While welding smoke particles can be between 10 nanometers and 2 micrometers in size, corona viruses are between 120 and 160 nanometers in size. Even for this particle size, general ventilation systems with appropriate filter quality have a filter efficiency of more than 99 percent. Due to the comparability of particle sizes, manufacturers also assume this high filter efficiency against viruses, so that operation is still possible without restrictions. It is important to look at the filter classes. The best general ventilation and extraction systems for welding fume extraction are equipped with class E12 filters.
Processes within plants are also likely to further reduce the spread of potential virus particles. This is because viruses encounter a layer of dry metal oxide dust, i.e., not a breeding ground. And on such surfaces, viruses are known to have a survival time of only a few hours. Since the general ventilation systems used for welding fume extraction generally do not have a heating or cooling function, the air purification processes do not cause additional hygiene problems.
By the way: general ventilation systems are only suitable for welding fume extraction as a supplement to local exhaust ventilation or in cases where collection at the source is not feasible. Some welders also wear personal respiratory protection at work. To protect against welding fumes, class FFP2 or FFP3 masks are generally worn.
