Are manometers or other pressure drop devices required by law on exhaust filters?

Are manometers or other pressure drop devices required by law on exhaust filters?

National Fire Protection Association

A means is required to make sure that you are moving the required amount of air for paint spraying. Your choices depend upon the code or standard adopted by your local authority. If NFPA 1 Fire Code is being enforced then the requirements spelled out in NFPA 33 Standard for Spray Application Using Flammable or Combustible Materials 2011 Edition would apply. NFPA 33 states that “Spray areas equipped with overspray collection filters shall have an effective means to ensure that the performance requirements of Section 7.2 are met.” [33:7.2.1] NFPA 33 also offer explanatory material that says that “Acceptable means to comply with 7.2.1 include, but are not limited to, visible gauges, audible alarms, approved interlocks, or an effective inspection program.” [33:A7.2.1] says that “Acceptable means to comply with 7.2.1 include, but are not limited to, visible gauges, audible alarms, approved interlocks, or an effective inspection program.” [33:A7.2.1]

International Fire Code (IFC)

If the IFC is being enforced then the requirements spelled out in Chapter 24 would apply. The IFC states that “Visible gauges, audible alarms or pressure-activated devices shall be installed to indicate or ensure that the required air velocity is maintained.” [IFC:2404.7.8.3]

Therefore, some means is required to ensure that the required air movement is maintained within the spray area. Both codes give you options. The intent of these requirements is to alert the operator of the point where the filters are loaded and can no longer pass the required amount of air. At that point, the filters need to be replaced.