Multi-Process Air Filtration for Aircraft Manufacturing

One Air Quality Solution for In-Tandem Sanding, Coating, and Painting

Aerospace and aviation components aren’t just large; they’re immense. Sanding, coating, or painting a single jet engine can require significant material handling and labor resources. Why? These processes produce airborne particulate matter that can contaminate sensitive aircraft components. Or worse, they risk employees’ exposure to hexavalent chromium compounds, such as chromium (VI), a known carcinogen. This is why these processes are usually performed in a separate designated area.

But it's risky in terms of quality control to transport aircraft wings or other large workpieces to designated sanding or coating areas. Surfaces are exposed to contamination every time a component is moved, such as airborne particles like dust or oil that can accumulate inside a hanger.

Permanent enclosures can help safeguard sanding, coating, and painting processes from air pollutants, but they’re not logistically viable for most maintenance hangers and facilities. Outsourcing surface work is another option, but it’s not cost-effective, especially when you consider the loss of internal quality control.

Fortunately, there is a logistically-viable air quality option that isolates air pollutants during surface maintenance. This versatile industrial air filtration technology allows sanding, coating, and painting in one workspace, in tandem, without exposure to hexavalent chromium or corrosive dust. This clean air solution is modular and customizable enough to adapt to painting, sanding, and coating workflows. First, let’s look at the air quality challenges surrounding each of these cellular workflows.

Sanding Air Quality Challenges

Traditional blasting, glass bead blasting, and sanding all produce particulate matter that’s especially hazardous in aerospace and aviation manufacturing. Working with aluminum surfaces on aircraft components releases toxic hexavalent chromium compounds into the air.

According to OSHA, safety risks from exposure to hexavalent chromium include:

• Rashes, swelling, and other allergic skin contact reactions, as well as damage to teeth enamel
• Runny nose, sneezing, or coughing, as well as burning and itching in the nose and throat from inhalation
• Nosebleeds, sores, or even stomach ulcers or lung cancer due to long-term exposure

Plus, aluminum dust can drift into every nook and cranny of delicate aircraft components and the shop floor, requiring excessive cleanup. Additional vac-sanding equipment can reduce excess dust and airborne particles. But this only covers about 80% of the toxic particulates, many of which are too small to see with the human eye.

Coating Air Quality Challenges

Coating is also hazardous work because the chemicals required to prevent aluminum corrosion are particularly toxic. For example, Alodine® is loaded with hexavalent chromium compounds. Yet aerospace and aviation manufacturers rely heavily on these coatings to ensure that every piece of the aircraft can withstand outdoor humidity or even salt air from overseas flights.

What’s more, employees must comply with OSHA standards when disposing of excess coating liquid waste. And as noted above, surface quality is compromised if coating work isn’t conducted in a clean air environment. Airborne particulates from sanding can easily compromise the coating gloss and can prevent the coating from adhering properly to the aluminum.

Painting Air Quality Challenges

While hexavalent chromium-loaded paints work exceptionally well at preventing moisture from corroding aircraft components during flight, they put employees at risk for adverse health effects. Plus, before any paint can be applied, workers must sand each workpiece to remove any old surface coatings. Aerospace and aviation manufacturing employees then face a double hexavalent chromium risk from paint and sanding particulate matter.

Aircraft paints may also contain volatile organic compounds (VOCs) and isocyanates which, like hexavalent chromium compounds, can withstand several years of flight missions. Less toxic paints are not an option for protecting aircraft surfaces, as these paints tend to be less durable.

A Multi-Process Air Quality Solution

From respiratory irritations to cancer risks, aerospace and aviation manufacturing workers face a host of health threats from exposure to indoor air pollutants produced by sanding, coating, and painting.

Thankfully, there is now a better air quality option to protect employees, which doesn’t involve cost-prohibitive material handling and excessive man-hours.

Duroair industrial air filtration technology, paired with a flexible clean air enclosure, can be custom-engineered for aerospace and aviation cellular workflows. A single retractable enclosure may include a six-stage air filtration system with two exhaust units specific to both sanding and coating/painting airborne particulates. This customization enables workers to simply change out the filters specific to the tasks being performed in the same enclosure.

Each enclosure, paired with Duroair multi-stage filtration technology, can:

• Capture the heavier, solid hexavalent chromium compounds produced by sanding or grinding in the first three filters
• Attack the smaller, gaseous hexavalent chromium particulates produced by painting via redundant carbon and UV-light filtering (last three filters)
• Capture 100% of airborne particulates, including hexavalent chromium and VOCs

Duroair can engineer an industrial air filtration system to collect air particulates and filter clean air to the outside. Or, if air makeup costs are an issue, we can design a system that isolates and contains particulates, then recirculates clean air back into the building. Recirculating the air can also speed dry times for coating and painting.

A single clean air solution can reduce the cost of sanding, coating, and painting by half, when looking at the time and material handling previously needed to perform each process in a separate designated clean room. Most importantly, this type of industrial air filtration can protect your most valuable assets – your employees.

Duroair custom-engineers clean air solutions to reduce overhead costs for specific, multi-process tasks. Our clean air experts can provide an in-depth evaluation of your hanger or facility to create an industrial air filtration system that will meet your budget and work with your floor plan and space limitations. Contact our industrial clean air experts today for a free consultation.