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Industrial Manuals, Standards and Codes I’ve Consulted

  When doing calculations, designing, and/or on-site work, we have to figure out which standard and code (federal, state, local) we will follow.   EPA and Permits EPA Title V Operating Permits (EPA) National Emission Standards for Hazardous Air Pollutants (NESHAP), Rule 6X for metalworking operations (EPA) Method 22: visual determination of fugitive emissions from material sources (EPA) Method 9: Visual determination of the opacity of emissions from stationary sources NAAQS (National Ambient Air Quality Standards)  On-site Measurement OSHA Technical Manual (OTM) Section II: Chapter 3, on-site Measurement (EPA) Method 22: visual determination of fugitive emissions from material sources (EPA) Method 9: Visual determination of the opacity of emissions from stationary sources Airborne Contaminants Cal/OSHA Title 8 Section 5155 - Airborne Contaminants OSHA (CFR, Title 29,1910) and Subpart Z - Toxic and Hazardous Substances OSHA 3348-05: Guidance for the Identification and...

What you have to know when applying blast gate damper

  Introduction A damper is a device that adjusts the volume of airflow passing through the outlet, inlet or duct. By proper adjustment of all dampers in a system, a desired distribution of airflows in all the branches can be obtained, while minimizing the total airflow of the system to save energy— this is also termed air balancing. The most common dampers used in industrial ventilation and dust collection systems to balance airflows are slide gate dampers (The slide gate, also called “blast gate or cut-off” damper). In a slide gate damper (see Figure 1 of a straight flat slide gate damper), the slide is inserted perpendicular to the flow. Figure 1 A sample of straight flat slide gate damper As the gate is sliding into the duct, it will add resistance to the airflow and consequently reduce the volume of airflow, while increasing airflows in all other branches. Withdrawing the gate has the reverse effect on that branch and all the others in a system. Interaction between a fan ...

Why and How to do Air Balancing on Industrial Ventilation and Dust Collection Systems?

  Introduction The performances of all the hoods in the whole system normally decide the success of industrial ventilation and dust collection systems from the point of a system owner’s view. The appropriate hood design and its needed airflow rate require the application of good ventilation practice, mastery of the technical knowledge and the ability and patience to do the mathematical calculations. When more than one hood is connected to one ventilation system, the design engineer has to assure that each hood can and will receive the volume of airflow equal or above its designed value and the whole system operates with the minimum possible airflow rate to save energy. This task is termed air balancing of the system or duct balancing. Unbalanced systems cause problems On the contrary, examine the case where one or more hoods are unable to receive desired volume of airflow from an unbalanced ventilation system. It is not uncommon that many hoods are receiving airflow volumes...