Welding Fume Extraction: Health Risks and Control Methods
Welding fume extraction controls the particle and gas mixtures produced during welding, which are invisible to the eye but can pose serious health risks. Their composition can vary according to the welding method, metal type, coatings and auxiliary chemicals used.
What Is Welding Fume?
Welding fume is a mixture of particles and gases generated during welding. It is often invisible to the eye but can have serious health effects. Its composition may vary depending on the welding method, metal type, coatings and auxiliary chemicals used.
Common components include:
Metals and Metal Oxides
Iron, aluminium, zinc, manganese, hexavalent chromium, nickel, beryllium, molybdenum, vanadium, cobalt, copper and others
Chemical Compounds
Silicates and fluorides
Toxic Metals
Cadmium, lead and chromates, especially from painted and coated surfaces
Volatile Organic Compounds (VOC)
Generated from paints, solvents and metalworking fluids (MWF)
Shielding Gases
Inert gases such as carbon dioxide, argon and helium
What Are the Health Risks of Welding Fumes?
Long-term exposure to welding fumes can lead to serious health problems. Particles in these fumes may be submicron in size and, when inhaled, can reach deep areas of the lungs.
Effects on Health:
Respiratory System
Irritation of the bronchi and lungs, chronic bronchitis and lung diseases
Nervous System
Neurological disorders caused by the accumulation of elements such as manganese
Cancer Risk
Increased risk due to carcinogenic substances such as hexavalent chromium and nickel
Organ Damage
Toxic effects on the kidneys and liver
Metal Fume Fever
Flu-like symptoms, particularly associated with zinc oxide exposure
Why Use Welding Fume Extraction Systems?
Workplace Safety
Protect workers’ health and help prevent occupational accidents and long-term occupational diseases
Regulatory Compliance
Support compliance with occupational health and safety regulations
Efficient Working Environment
Clean air improves employee productivity and comfort
Equipment Protection
Prevent smoke and particles from damaging machinery
Welding Fume Exposure Limits
Because long-term exposure to welding fumes can cause serious health problems, health and safety organisations establish exposure limits. These limits are used to control workplace air quality and protect employees.
OSHA (Occupational Safety and Health Administration)
PEL (Permissible Exposure Limit) for total welding fume: 5 mg/m³ as an 8-hour time-weighted average (TWA), for mild-steel, iron or aluminium welding operations.
Additional limits apply to individual elements. OSHA has established lower PEL values for substances commonly found in welding fumes.
ACGIH
ACGIH recommends TLV (Threshold Limit Values) based on TWA, an 8-hour time-weighted average.
Ceiling limits are established for some contaminants. These values are health-based and rely on scientific risk assessment rather than technical feasibility. They are generally more stringent than OSHA limits.
Important Notes
Each country can establish its own legal limits based on the guidance of bodies such as OSHA and ACGIH. Employers are responsible for providing ventilation systems, extraction units and personal protective equipment that keep exposure below applicable limits.
Welding Fume Control
The primary objective of welding fume control is to reduce harmful particle and gas concentrations below established exposure limits. This can be achieved through two main methods:
1. Exhaust Systems
In these systems, contaminated air generated during welding is exhausted directly outdoors. Make-up air must be supplied so that indoor pressure remains balanced.
An amount of clean air equal to the exhausted volume must be brought in from outdoors or conditioned systems.
These systems are generally simpler and lower in cost; however, heat loss and energy consumption can be high. Environmental-emission conditions must be checked and filtration may be required.
2. Filtration Systems
In this method, welding fume is filtered using dust-collection filters, HEPA filters or specialised cartridge systems.
The air is then returned to the facility or discharged outdoors after suitable treatment.
Advantages:
Energy efficiency, especially in air-recirculation systems
Reduced heat loss in enclosed areas
More precise filtration to help remain below exposure limits
Source-Capture Extraction Systems
For welding fumes to be collected effectively, they must be captured at the point where they are generated. This can be achieved with the following equipment:
Articulated Extraction Arm
Its flexible structure allows it to be positioned close to the welding point.
It is one of the most effective solutions for local fume capture.
It operates in integration with a filtration or exhaust system.
Downdraft Welding Table
Creates downward airflow from the table surface where welding is performed.
Fumes are drawn downward at the source and filtered.
It is particularly preferred for small parts and repetitive welding operations.
Key Considerations When Selecting a System
Welding type, such as MIG, TIG or stick welding
Size and stability of the workpiece
Size of the working environment and existing ventilation infrastructure
Filtration needs and indoor-air-quality targets
Industrial Air Filtration Systems
Specially designed air-filtration systems are required to effectively control welding fumes and other contaminants generated in industrial production processes. Standard HVAC systems alone are not sufficient to filter these types of contaminants.
Filtration Technologies Used
1. Dry Filtration (Dust Collectors)
Contaminated air is cleaned through filters and clean air is returned to the environment. Common dry-filter types include:
Cartridge Dust Collectors
Compact design and high efficiency
Commonly preferred for welding and metalworking processes
Easy maintenance and long-life filter elements
Bag Filter Systems
High-volume dust-collection capacity
Used in heavy industrial applications
Cyclone Separators
Used as pre-filters
Effective in separating large and heavy particles
2. Wet Filtration (Wet Scrubbers)
Contaminants are separated from the air through a water curtain or spray system.
These systems are particularly preferred for flammable or explosive dusts.
Cleaning and maintenance intervals may vary.
Applications:
Processes involving highly reactive metals such as aluminium and titanium
Processes with a high explosion risk
Spark Risk and Combustible Dusts
Where combustible dust or spark risk is present in dry-filtration systems, an integrated spark trap or fire-suppression unit should be added.
When dry cartridge or bag-filter units are used, pre-separation with spark-arresting units may be used to eliminate potential spark risks.
Article Content
Exposure Limits for Welding Fume Components
Welding Fume Extraction with an Articulated Arm
Welding Fume Extraction with a Downdraft Table
Wet Filtration Unit
Cartridge Dust-Collection Unit
Spark Separator Unit
Sources
OSHA (2013) Fact Sheet: Controlling Hazardous Fume and Gases During Welding, DSG FS-3647
Brand, P., Lenz, K., Reisgen, U., & Kraus, T. (2013). Number size distribution of fine and ultrafine fume particles from various welding processes. Annals of Occupational Hygiene, 57(3), 305–313.
Chemical composition and morphology of welding fume particles and grinding dusts. American Industrial Hygiene Association Journal, 53(5), 290–297.
Brand, P., Lenz, K., Reisgen, U., & Kraus, T. (2013). Number size distribution of fine and ultrafine fume particles from various welding processes. Annals of Occupational Hygiene, 57(3), 305–313.
