Why Fume Extraction is so Important!

Welding & Hexavalent Chromium

The chromium found in stainless steel is converted to its hexavalent state during the welding process, and these highly toxic fumes can pose some serious health consequences, not the least of which being lung and larynx cancer.

Let’s bear in mind as well that a single welder can produce 20 – 40 g of fumes per hour, or upwards of 70 kg a year.  That is a lot of weld smoke that may contain some pretty nasty elements, and some of these particles are fine enough to penetrate deep into the lungs (anything from 0.1-5 µm)

There are OSHA regulations pertaining to hexavalent chromium.  The permissible exposure limit, for example, is 5µg/m3 as an 8-hour time-weighted average.  I don’t quite understand how a welder is supposed to monitor these things to make sure he or she isn’t exceeded these permissible limits.  Naturally, it is incumbent on management and health-and-safety professionals at each facility to take the appropriate measures to ensure that their team members aren’t being subjected to exposure beyond these limits.

If you want to read-up on the OSHA regulations as it pertains to hexavalent chromium – Cr(VI) – check out 29 CFR 1910.1026 and 1926.1126.

https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1026

https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.1126

For welders, to protect yourself you should insist on some form of ventilation to remove gases from your breathing zone.  Any at-the-source solutions should be given top priority.  You should also avoid welding in confined spaces without the aid of proper ventilation.

I’ve always sympathized with office staff who must occasionally walk out onto plant floors in facilities that do not employ a form of fume extraction.  Even though their exposure may be limited, they’re nonetheless being exposed to a nasty group of compounds.  I was in a shop recently with a health-and-safety professional witnessing plumes of weld smoke envelope a welder, before drifting to the ceiling.  The welder was wearing a respirator, but we certainly weren’t.  When I inquired about them employing a form of weld fume extraction, the person I was with literally walked up to the welder and asked if he thought it was necessary.  When he answered he didn’t she simply parroted what he said.  It begged the question – aren’t you the person best suited to make that determination?


Looking to Invest in Fume & Dust Extraction?

Below is a simple 11-point checklist for those looking to invest in a mobile fume & dust extraction system.  This may prove helpful as you review your options, and consider your particular needs.

This particular list is more pertinent for this performing heavy-duty welding. If your application calls for light or intermittent use, this check list might be overkill.  If that is your situation, and you’d like to know what is available to you, please feel free to reach out.  We’re here to help.

11-Point Mobile Fume & Dust Extraction Checklist

  1. Fan silencer included as standard
  2. Lockable wheels
  3. How is the Fan actuated? Is it via a physical switch, or by a welding sensor clamp?
  4. Fan start and light switch on the hood
  5. LCD display: for notification of the status of the fan, if the unit needs to be serviced, and if it is time to change the filter
  6. Customization via the push of a few buttons: select fan delay off time for automatic start, set automatic cleaning (on or off), & timer cleaning intervals
  7. Automatic cleaning of the main filter cartridge
  8. Mechanical and compressed air process to clean the main filter.

Why is this important? During use dust bridges are created between the pleats.  These dust bridges contribute to filter load, and cannot be cleaned exclusively with compressed air.  You want a mechanical method to break these dust bridges. Typically, this is mechanical cleaning method is performed as the filter rotates during cleaning. While this is happening, compressed air is blown from the inside to expel the dust bridge out of the pleat.  This type of process results in a cleaner filter, greater filter longevity, and overall cost savings as you don’t have to replace filters as often.

  1. Automatic damper – to prevent dust from leaking out during compressed air cleaning
  2. Easy removal of the dust bin
  3. HEPA filter – can this be added as an option?