P.O. Box 410
Schofield, WI 54476

Phone: 715.359.6171
www.greenheck.com

Fan and damper applications may involve the handling of potentially explosive or flammable particles, fumes, or vapors. Such applications require careful consideration of all system components to ensure the safe handling of such gas streams. In order to assist end users with the specification of spark resistant products, the Air Movement and Control Association International (AMCA) has developed standard 99-0401, Classification for Spark Resistant Construction. The purpose of this standard is to establish general construction guidelines for fans and dampers that are intended for use in spark resistant applications.

AMCA 99-0401 was initially developed as a reference for the specification of centrifugal utility blower models. However, over time, other fan types have appeared in specifications for use in spark resistant applications. As a result, many manufacturers have chosen to offer fans with levels of construction that meet the intent of AMCA 99-0401, despite the fact that these fans may not fully conform to the guidelines established by the standard. As of the release date of this bulletin, there is neither a physical label nor testing protocol for certifying the spark resistance level of a fan.

In order to meet the requirements of spark resistant applications, Greenheck offers several options and accessories including varying levels of aluminum construction, EXP motor enclosures, shaft seals and rub rings on most fan models. We have gone to great lengths to ensure or methods of construction and choice of alloys meet the intent of AMCA 99-0401. Ultimately, it is the customer who must choose the type of fan, materials and design because they are in the best position to understand the inherent risks given the limitations of the AMCA standard, the ambient location of the installation, the degree of protection required by the application they are selecting for and the maintenance requirements of the materials selected. 

Please note that Greenheck takes exception to note #1 of the standard on fan models where the bearings, drive components or motor may be in contact with the airstream of the fan. It is up to the discretion of the consulting engineer to approve of any such exceptions and make the final determination on which fan models are acceptable for spark resistant applications. It is also the responsibility of the consulting engineer to specify any options or accessories that are required to meet the intent of the desired level of spark resistant construction from AMCA 99-0401. As the system designer, the consulting engineer, must advise the end user in assessing the risks and identifying the safest selection. Greenheck is not in a position to consult on what modifications are necessary to make an acceptably safe system for any specific application or environment. Especially where the hazards are extremely severe, end users need to add more detailed specifications and consult with an expert to mitigate the risk that an unsafe condition could arise.

For clarification or questions please refer to AMCA 99-0401 construction guidelines.