Q. Why do I need a fume extractor? What are the hazards of welding smoke and fumes?

A. There are more than 80 different types of welding and they are hazardous for various reasons. The main reason is that particles and gases that create adverse side effects can be inhaled during the welding process. When heated rapidly, part of the metal is vaporized and becomes sub-micron particles in the air that you breathe. Many of these metals can be quite toxic including chromium, nickel, arsenic, asbestos, manganese, lead and zinc.

For more information, download this document from Occupational Safety and Health Administration.

Q. Which fume extractor is right for my application?

A. Depending on your application you will need to consider the number of work stations, size and type of filter, and type of filler metal to be used. You will also need to determine your filter requirements. For example, will there be one main filter for several small stations or will each station require its own source capture and individual filter? Will you be working in a fixed area or will you need the fume extractor to be portable? These and other factors come into play when determining which fume extractor is ideal for your situation. We often ask customers to take a picture of the shop layout and email it to us so that we can help with recommendations.

Q. Are fume extractors designed for indoor or outdoor use?

A. The majority of our customers use Enviroflex products for indoor applications where there is no natural ventilation and fumes or smoke need to be removed from the work area, filtered, and recycled back into the plant to maximize customer safety.

Q. How will I know when it’s time for a filter replacement?

A. This depends on the filter media you are using.

Media type
If you are using media type filters (disposable panel or cartridge type filter) you will notice that the unit will start losing suction. Once you reach this stage it is time to either replace or clean the filter

Electrostatic type
If you neglect to clean the electrostatic filter the unfiltered particles will be become visible coming out of the back end of the air cleaner. Ideally, you will have a preventative maintenance program to clean your filter so that your equipment is continuing to perform its fume extraction function properly.

Q. What is a HEPA filter?

A. HEPA filters are rated at capturing 99.97% of weld fume particles at 0.3 microns. HEPA filters are often used with respirators and are an optional addition to the ESE handheld and the Enviromac system. HEPA filters are known for their effectiveness in removing the hazardous hexavalent chromium fumes generated when welding stainless steel.

Q. Can the filters I purchase from Enviroflex be cleaned and reused?

A. We offer both reusable filters as well as throwaway filters, depending on your need and application.

Q. What makes one filter type preferred over another? How do I choose which is right for my application?

A. To determine which is right for your application consider what your main priorities are – ongoing replacement costs, high efficiency, electronic?  A washable filter can easily be washed with water or blown out with compressed air but if your team forget this critical maintenance function, the filter loses its effectiveness. Throwaway filters, on the other hand, trap particles and hold them which eventually makes the filter so efficient it won’t pass air.

Q.How far away should the moveable extraction duct be?

To work this out, first note the dimensions of the ‘face’ or opening on the extraction duct. Take the shortest dimension (typically about 300mm). The extraction should be positioned about 1-2 times the diameter of the hood, vertically above the welding point. If it’s much closer, the welder will often have problems seeing past the hood. If it’s too far away (over 2x diameter) then fume will tend to disperse and a large proportion of the fume will not be captured. The unit loses 90% of its face velocity at one diameter out. For example, with a 12” hood suction speed is 2000 ft/min but add a distance of 12” from the welding arc and the suction speed diminishes to 200 ft/min.

Enviroflex® International Inc. (c) 2013