Source Capture vs. Ambient: Two Important Air Filtration Methods

Welding is a process where there are many different methods, such as shielded metal arc, gas metal arc and submerged arc. Since the practice involves the use of sophisticated tools and equipment, workplaces have to ensure their employees are protected at all times. Welders often shield themselves by wearing protective clothing, in addition to a goggles and welding helmets. However, workplaces must also ensure their air filtration systems are properly working because the fumes from welding can become quite hazardous. Luckily, two filtration methods exist: source capture and ambient. Each filtration system has unique traits that workplaces need to be aware of.

Dangers of Welding

Even though workers can protect themselves while welding, the process still results in other side effects that can be potentially dangerous to an individual’s health. To ensure welders are protected while working, the U.S. Occupational Safety and Health Administration has developed standards that building management must abide by.

For example, welding standards for construction industries are quite thorough. Per section 1926.353(c)(1) of OSHA’s Safety and Health Regulations for Construction, any welders working in an enclosed space must do so only if the local ventilation system meets OSHA standards. One of the agency’s rules states that oxygen must not be used for ventilation reasons. If, sufficient ventilation is not possible, employees must be outfitted with air line respirators.

Employers must ensure workers are protected because welding can lead to severe illnesses for workers. Most notable is metal fume fever, which is caused by exposure to fumes. This illness leads to flu-like symptoms, and individuals will typically experience periods of fatigue, nausea, headaches, chills, high fever, chest pain and more. According to Weld Guru, a metallic or sweet taste can also develop in the mouth, and this will distort the taste of food and liquids.

More severe metal fume fever symptoms may include vomiting, skin rash and convulsions. But for most individuals who contract the illness, their symptoms will go away within 24 to 48 hours. Individuals will feel completely healthy after four days.

Unfortunately, the exact cause of metal fume fever is not known, but there is reason to believe that workers often breathing metal oxide fumes could be a contributing factor. This may then lead to an immune reaction that causes modified proteins in the lung to act as allergens.

Metal Guru also stated zinc, magnesium and copper tend to result in the dangerous fumes workers may breath.

Source-Capture Ventilation

The best way to make sure workers do not fall ill from metal fume fever is to have ventilation systems installed throughout the area where welding takes place.

“Source capture through fume extraction should be utilized in order to remove fumes.”

As such, source capture through fume extraction should be utilized in order to remove fumes created from welding. With source capture, harmful and dangerous particulates are minimized before they can cause damage to a worker’s respiratory system.

Four types of source capture ventilation work best to protect welders:

• Fume arm systems
• Tip extraction
• Overhead hood
• Downdraft tables

A building’s manager will have to decide which type of source capture system works best throughout a building’s setup. For example, overhead hoods are suitable for large workspaces where smoke and fumes have to be contained. These systems then isolate the welding fumes to make for easier breathing. As a comparison, downdraft tables are built to draw fumes down and away from the worker as he or she breathes.

There are some downsides to source capture systems, however. In particular, managers may find it difficult to install these types of ventilation systems due to existing building infrastructure that might not be able to be reconfigured. In other instances, individual welders may prefer to have freely movable hoods that can provide a sufficient airflow and remove any fumes.

Ambient Air Filtration

Ambient air filtration systems can be installed in overhead spaces to draw fumes upward. From there, the air can be circulated to create an airflow that will maximize the benefits of clean air.

While there is a clear distinction between ambient and source capture air ventilation systems, leadership and building management should not think of one as a replacement for the other. Instead, source capture and ambient systems should be used together for maximum benefits.

With metal fume fever affecting welders across the country, managers have to ensure they are doing everything possible to protect workers. This involves abiding by OSHA and other compliance regulations, in addition to installing the necessary air ventilation systems.

Together, ambient and source capture systems will help alleviate the dangers welders face.

Contact Air Impurities Removal Systems for more information and ways to protect welders from metal fume fever. Employers will find numerous options to choose from, including mobile and bench-top fume extractors and downdraft tables.