Welding Fume: Education Provider Case Study
Auto Extract Systems was invited by a well-established college, who pride themselves in providing high-quality education and training from foundation studies through to degree level courses, to provide an effective LEV (local exhaust ventilation) solution for the safe removal of welding fumes in their engineering training centre’s fabrication area, which strictly worked in accordance with HSG258: Controlling Airborne Contaminants at Work: A Guide to Local Exhaust Ventilation (LEV) guidance.
The challenge was to provide an effective LEV solution for the college’s 46 welding stations in various locations in the training facility and safely duct captured fumes to the atmosphere through the nearest roof or wall to disperse through a high-velocity cowl, as per the HSE’s HSG258 guidance.
Four LEV systems were prescribed to safely remove the fumes generated from the welding process. A total of 46 x 160mm diameter, two-metre-long self-supporting hose extraction arms were connected to four fans through common ducts.
The first system consisted of 10 x hose extraction arms that were connected to an 11kW centrifugal fan, which can achieve 13,500m3/h free blowing, maximum pressure 3,600Pa. The second system consisted of eight extraction arms that were connected to a 7.5kW fan, which achieves 13,300m3/h free blowing, maximum pressure 3,300Pa. Whilst the third and fourth system both consisted of 14 extraction arms that were ducted to two 15kW fans capable of achieving 16,000m3/h free blowing, maximum pressure 3,600Pa.
The hose extraction arms specified featured an ergonomically designed hood which is ideal for the collection of hot welding fumes and gases and is easy to operate 4-way centre joint. The capture hood features a flat base to take benefit from the Coanda effect; the phenomenon is known to Science when a jet of air clings to a flat surface over a longer length than it would over towards an open collection area, enabling a greater collection of fumes over a longer length than any traditional type all round hood. In addition, the capture hoods featured a centrally fitted 24v LED light to illuminate the workpiece for students.
With 46 workstations complete with LEV, the university’s facilities manager commended Auto Extract Systems, stating: “From start to finish, the team at Auto Extract Systems were professional and installed four comprehensive systems to meet our facility’s needs. We now have enough that will protect students and staff whilst in the engineering facility.”
Auto Extract Systems continue to maintain the LEV system installed with an annual LEV Test. LEV Testing is a legal requirement and should be tested at least once in a 14-month period for compliance with HSE standards; they often form part of a company’s insurance requirements too. We also recommend that LEV equipment should be serviced at least every 14 months and more frequently if its usage is high (find out more about LEV servicing), so it operates within its required benchmark performance and reduces hazardous substances exposure.