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One of the issues facing the Thermographic industry is providing the assurance to customers that surveys are performed properly and that the reporting provides sufficient information to give the desired answers. Reputable thermographers are continually fed with competitors who provide services which are either imKcurate, improperly carried out or interpreted, or which do not satisfy the client. This less than satisfactory service continues to threaten the acceptance of all thermographic applications. The American Society for Testing and Materials (ASTM), has been in the business ofproviding uniform, generally accepted standards for testing for over 90 years. The standards published by ASTM go through an extensive review phase which assures that the fmal standard reflects industry standards. Additionally, standards are periodically reviewed for changes which assures that they contain the latest technology. ASTM Cl 153-90 is the recently approved ASTM Standard Practice for the Location of Wet Insulation in Roofing Systems Using Infrared Imaging. The scope of the standard is limited to those techniques which employ the use of JR imaging systems at night to locate and delineate areas of wet roof insulation located above the deck and below the waterproofing system of a roofing system. The practice outlines the minimum criteria for the infrared imaging systems, the effect of meteorological conditions, roof construction, and verification criteria. The standard also states the minimum necessary operating procedures for a successful survey. It is not the intention of this standard to present all of the principles which apply to the application of infrared technology to roof moisture surveys but rather to outline the minimum criteria for an acceptable infrared roof moisture survey. ASTM standards are divided into sections which correspond to the various functions of the standard. In addition to a statement of the scope of the standard, all standard practices must include a section on Significance and Use2. Other sections which are included in this standard practice are: Terminology Infrared Survey Techniques Instrument Requirements Level of Knowledge (of the operator) Limitations (Applicability of Constructions) Significant Environmental Parameters Required Conditions Inspection Procedures Data Interpretation Verification Report Precision and Bias This paper will discuss the key elements of each of these sections and in particular those elements which were developed specifically for the roof examination standard practic
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