Welding fume removal from the work space is mandatory. Current OSHA standards for welding fume were lowered to levels difficult to achieve without proper ventilation. Exposure to Beryllium, Cadmium, Hexavalent Chromium and Manganese have very low threshold limit values. Source capture fume extraction is the most effective way for complying with current regulations.
A source capture welding fume extraction system must be user friendly. The design of the system in most cases will include;
- fume extractor arms
- downdraft welding tables
- custom welding hoods
- welding fume extraction guns
Some weld shops work on larger pieces that make source capture extraction difficult to achieve. These projects use ambient filtration such as;
- Welding booths
- Air Cleaners
- Push pull Ventilation Systems
- Dilutor Ventilation System
In both types the importance of user friendliness and code compliance is a primary concern. Clean Air Company designs and installs welding ventilation systems that are user friendly. We provide guidance for a cost-effective ventilation solution. This will include the evaluation of long term operational and maintenance costs.
Selecting from our broad range of fume extraction equipment can be challenging. We outlined the pro’s and con’s of the various types of equipment from the most commonly used to least common application.
Extraction Arm Capture Benefits:
- Local fume extraction – extremely effective
- Movable fume hood and can be positioned where needed
- Provides wide working range of coverage for fume collection
- Accessories provide welding exhaust fan control, flow control, energy savings and additional lighting
Extraction Arm drawbacks:
- Not effective at capturing grinding dust
- Must be repositioned if doing long seam welds
- Requires user interaction with fume hood
Downdraft Welding Table Benefits:
- No user interaction with positioning fume hood
- Effective at capturing both welding fume and metal grinding dust
- Provides work surface, filtration and lighting all in one
- Simple plug and play installation, no duct and easily movable
Downdraft Table Drawbacks:
- Not versatile to go from small parts to large parts
- Fixed work space.
Custom welding Hood Benefits:
- Provides effective source capture
Drawback of Custom Welding hoods:
- Fixed location with limited working range
- More likely to be damaged
Benefits Fume Extraction Welding Gun:
- Extremely effective fume source capture
- Excellent for enclosed space welding and long seam welds
- Increased visibility
Drawback of welding fume extraction gun:
- More expensive cost per welding station
- Larger welding gun
Dust Control booth benefits:
- Customized to fit your needs including crane slots for large pieces
- Regain air for effective capture and control of welding fume and grinding dust
- Enclosed work area with additional lighting
- Self-contained air filtration and self cleaning filters
Dust Control booth drawbacks:
- Takes up more floor space
Air Cleaner benefits:
- Allows coverage of large areas at minimal cost
- Constant air turn-over and filtration
- No human interaction for usage
Air Cleaner Drawbacks:
- More frequent filter replacement maintenance
- Not as effective as source capture
- Requires more man hour service maintenance
- Large volumes of air turn over for constant filtration
- Covers large areas
- Central dust collection typically higher filtration efficiencies
- Self-cleaning cartridge collector filters means less maintenance
Push Pull Ventilation Design Drawbacks:
- Not as effective as source capture
- High initial capital investment
In many cases welding fumes need to be filtered before returned into the plant or exhausted outdoors. We have the ability to design for both. Exhaust in the summer months and return air in the winter months. Dust collectors for welding fume are selected based on several factors.
- What type of welding are you doing? (Mig welding, Tig welding, Stick welding)
- What type of material are you welding? (Aluminum welding, Stainless Steel welding, Galvanized Steel welding)
- How much are you welding ? (based on weekly consumable usage)
- How many welders are there?
Based on the answers to the above we can:
- Size your dust collector
- Suggest the proper filter media for the dust collector
- Offer spark arrestors
- Determine if fire suppression is required
- Provide a properly design duct system layout.
Zinc Oxide Fumes: May cause a condition called Metal Fume Fever. Metal Fume Fever victims have symptoms similar to the flu. These may include, but are not limited to: chills, nausea, muscle aches, decreased pulmonary function and difficulty breathing.
Hexavalent Chromium Fumes: Are a known human carcinogen for lung cancer. Small amounts of exposure have lasting negative health effects and exposure may lead to many other types of cancers . Other effects: nose & throat irritation, wheezing, asthma, and damage to the skin, eyes, kidneys and liver.
Iron Oxide Fumes: May cause Siderosis, a lung disease that results from particle lung deposits. Siderosis can cause nasal and lung irritation
Manganese Fumes: Chronic exposure to Manganese can cause Manganism, a condition that affects motor skills ad brain function in a manner similar to Parkinson’s disease. This results in trembling, stiffness, slowing of motor movement, and in severe cases anxiety, depression and aggression. It may also cause lung, liver, or kidney damage.
Mild Steel: Breathing these fumes leads to an increased risk of lung cancer .
Nickel Fumes: Causes eye, nose, or throat irritation and may also lead to and lung problems.
Other Welding Irritants
Aluminum Fumes: irritates the respiratory system.
Copper Fumes: may cause irritation in the eyes, nose or throat.
Fluorides: Acute effect is irradiation of eye, nose and throat. Long-term effects include bone and joint problems or fluid in the lungs.
Molybdenum: Eye, nose and throat irritation and shortness of breath.
Vanadium: Immediate issues are eye, skin and respiratory tract irritations. Long term exposure may result in bronchitis, retinitis and pneumonia.
|Metal||ACGIH TLV™ (8-Hour TWA)|| NIOSH REL |
| Not |
|Beryllium||.05 µg/m3||0.2 µg/m3|| 0.2 µg/m3 |
|Cadmium (as Cd)||.01 mg/m3||Re-Evaluating||.005 mg/m3|
| Copper (Fume)|
|Hexavalent Chromium||0.2 µg/m3||0.2 µg/m3||5 µg/m3|
|Iron Oxide||5 mg/m3||5 mg/m3||10 mg/m3|
|Manganese|| 0.2 mg/m3|
|0.2 mg/m3||5 mg/m3|
| Nickel |
| 0.05 mg/m3|
| Zinc Oxide|