A large transit bus manufacturer was directed to make a change to improve the health and safety of the workers welding the metal vehicle frames. The materials they are using emit gasses that are hazardous to workers and can cause long term negative health effects. To counteract this, the Health and Safety department settled on a type of welding hood that uses a vortex style ventilator. This not only supplies fresh breathing air but also cools the workers during unseasonably hot conditions in summer.
The Engineering department was advised that each of the 110 ventilators would consume 15 cfm on top of the additional air required for desiccant style breathing air purifiers that would consume 15% of their nameplate rating as purge air. To feed the expected peak load, the compressed air supply needed to be doubled from the existing 500 hp total capacity to a larger 1000 hp size. This size increase would cost considerable funds to purchase and would significantly increase the compressed air operating costs due to the lack of adequate storage receiver capacity and lack of space to install any new volume. Read More