scope:

This document gives reasons for doing inspections of air handling systems, provides outlines that can be used to organize and conduct inspections, and sets forth checklists that call attention to the basic features of ductwork and items placed in duct systems.

It presumes that SMACNA's construction standards are used as the basis of compliance, whether they are explicitly invoked in contract documents or in codes. No attempt is made to segregate designer's inspection obligations from those of code officials.

It is primarily prepared for commercial HVAC systems; however, similar principles would apply for residential or industrial work inspection. Furthermore, it assumes that prescription specifications apply rather than performance specifications. Performance specifications typically call for HVAC systems to maintain control of the environmental within certain tolerances. Whether the duct system has the specified airflow rate, maintains air temperature, humidity, degree of cleanliness, etc., or whether it controls room air motion and pressure differentials in relation to adjacent spaces are separate matters of design and testing and balancing that are already dealt with in numerous handbooks and standards. An overview of the functions of duct systems is given in Appendix A.

Finally, although this document covers some items that are safety related, this document is not a safety inspection guide. It is presumed that the applicable codes and system designs that are allowing use of the SMACNA standards and manuals address safety issues independently.