Construction welders regularly need to enter confined spaces in boilers, tanks, or pressure vessels to perform repairs or during the manufacturing process. Both MIG welding and TIG welding use inert gas that's heavier than air and that has the potential to displace oxygen and create a major hazard for the welder. Because of the inadequate ventilation of confined spaces, the heavy gas has the potential to literally submerge a worker. And because it's colorless and tasteless, it's easy to miss until you really have a problem. To avoid a very regrettable displacement of your oxygen supply, you're going to need to ventilate. One of the simple systems we sell are the ECKO K2025 Confined Space Blower, Duct and Canister. This is an 8 inch blower/ventilator that's attached to canister that holds 25 ft. of flexible ducting to direct the airflow. The blower and canister are made of durable, lightweight, dent- and chemically-resistant polyethylene. Durable enough for the types of jagged edge locations where welders often find themselves. Generally speaking, supplied air ventilation, or the act of pushing clean air into a confined space, will provide better results than trying to pull the bad air out. Though requirements differ by state and country, a complete air refreshment of 7 times per hour is standard. To accomplish this, you'll need to know not only the size of the space you're about to work in, but also the CFM rating of your ventilator. CFM stands for cubic feet per minute. Us the chart below by drawing a straight line from the size of your space to the capacity of your blower, and you'll have a good idea of how much time you'll need to purge the area of foul air. If you have questions about confined space ventilation, please don't hesitate to give us a ring at 1-800-892-9580.