Envirochem visited the bespoke oak craft manufacturer to carry out tests of the LEV system in the woodworking workshops to ensure the dust hazards were removed effectively by the system.
Envirochem attended the site in Burley and carried out an inspection to identify where the separate fan systems were and which pieces of machinery were attached to which system. A schematic was then drawn indicating which fan system was in place and where the ductwork from the fan leads to different pieces of machinery. Appropriate test points were then identified, this involved drilling a 9mm hole into a parallel, straight section of metal or hard plastic ducting at least two diameters away from obstructions or beds or manually making a hole in flexible plastic ductwork. A pitot tube is then inserted directly into the ductwork parallel to the flow. At least five readings for static pressure (Pascals) and transport velocity (m/s) at different positions across the diameter at the sampling point and the average value were determined using a calibrated Airflow PVM100 micro-manometer with the individual shutters closed and open for each piece of machinery. Face velocities were taken where there was access to the extraction hoods. Readings are taken across the face of the hood and an average value taken. A bespoke report was written which showed separate diagrams of the fan exhaust systems, indicating whether the individual pieces of machinery had passed the test and when the next test was due.
The results can be used to determine whether upgrades are needed on the fan systems and whether filter cleaning is required to improve performance.