ASTM-D7391 Standard Test Method for Categorization and Quantification of Airborne Fungal Structures in an Inertial Impaction Sample by Optical Microscopy

Show Complete Document History

Document Center Inc. is an authorized dealer of ASTM standards.
The following bibliographic material is provided to assist you with your purchasing decision:

Standard Test Method for Categorization and Quantification of Airborne Fungal Structures in an Inertial Impaction Sample by Optical Microscopy



Want this as a site license?


1.1 This test method is a procedure that uses direct microscopy to analyze the deposit on an inertial impaction sample.

1.2 This test method describes procedures for categorizing and enumerating fungal structures by morphological type. Typically, categories may be as small as genus (for example, Cladosporium) or as large as phylum (for example, basidiospores).

1.3 This test method contains two procedures for enumerating fungal structures: one for slit impaction samples and one for circular impaction samples. This test method is applicable for impaction air samples, for which a known volume of air (at a rate as recommended by the manufacturer) has been drawn, and is also applicable for blank impaction samples.

1.4 Enumeration results are presented in fungal structures/sample (fs/sample) and fungal structures/m3 (fs/m3).

1.5 The range of enumeration results that can be determined with this test method depends on the size of the spores on the sample trace, the amount of particulate matter on the sample trace, the percentage of the sample trace counted, and the volume of air sampled.

1.6 This test method addresses only the analysis of samples. The sampling process and interpretation of results is outside the scope of this test method.

1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Significance and Use

5.1 This test method is used to estimate and categorize the number and type of fungal structures present on an inertial impactor sample.

5.2 Fungal structures are identified and quantified regardless of whether they would or would not grow in culture.

5.3 It must be emphasized that the detector in this test method is the analyst, and therefore results are subjective, depending on the experience, training, qualification, and mental and optical fatigue of the analyst.


bioaerosol; fungal; fungal structures; fungi; fungus; impaction; impactor; indoor air quality; mold; mould; spore; spores;

To find similar documents by ASTM Volume:

11.07 (Atmospheric Analysis)

To find similar documents by classification:

07.100.99 (Other standards related to microbiology)

This document comes with our free Notification Service, good for the life of the document.

This document is available in either Paper or PDF format.

Document Number


Revision Level




Modification Type


Publication Date

April 7, 2020

Document Type

Test Method

Page Count

13 pages

Committee Number