A New Standard for Mold Assessment

The ASTM D7338 standard sets the bar for best practice for assessing fungal growth in buildings. A sampling guide and strategy will be one of the next work items for the subcommittee.

• By Jerry Laws
• Apr 01, 2011

Having just returned from the Indoor Air Quality Association's annual meeting and Indoor Air Expo held Feb. 14-17 in San Antonio, Lisa Rogers, president of Mycometer US, said most attendees focused on the standard IAQ issues: ventilation, remediation, mold, and moisture. They were interested in efficiency, different ways of using resources, and ways to differentiate themselves in the market -- to "get an edge," she said.

Rogers, who chairs Subcommittee D22.08 on Sampling and Analysis of Mold, part of ASTM International Committee D22 on Air Quality, could help. The subcommittee had recently completed ASTM D7338, Guide for the Assessment of Fungal Growth in Buildings, a needed standard that will be a reference for anyone who tests for mold in buildings.

D7338 is the second standard finished by the subcommittee, which has about 70 members and was formed in 2005. "We're working on four or five work items now," said Rogers. "It [D7338] has taken the full five years. It has been a very controversial standard from the very beginning and has gone through many edits. About a year and a half ago, it was so controversial that we basically dumped the whole draft work item that we'd been working on and started over."

This was done, she explained, because of some conflicting components in the draft, one of which was a discussion of occupant health. Rogers said that subject is not part of the subcommittee's task, however; members wanted the standard to address only the test procedure and not to include health. "Initially, the standard was trying to be too many things in one document," she said. "When you start adding too many things in there, it starts diluting not only the intent, but the message. A couple of years ago, we said, 'Let's just distill that down to what we want this particular document to be. And we can move on to the next phase of it.' "

The D7338 standard discusses sampling briefly. A sampling guide and strategy will be one of the next work items for the subcommittee. "That's really critical, one of the next critical guides," Rogers said. "I don't want it to be controversial. It's one of those issues that there are a lot of different considerations in a building, and in some ways each building is unique. So we have to be able to write a standard practice that gives guidance that is not restrictive. We don't want to take away the thought process that the consultant or the practitioner is going to need. . . . It is going to take some time."

Mold remains a hot topic in state legislatures, according to American Industrial Hygiene Association Government Affairs Director Aaron K. Trippler, who reported Feb. 23 that his department was tracking 11 mold-related bills this year in Arkansas, Arizona, Florida, New Jersey, New York, and Rhode Island.

D7338 Standard Sets the Bar
Rogers has worked in various roles in industrial hygiene for more than 30 years, including a long consulting career and work on issues including asbestos, lead, and mold. She said she has always been involved in IH and environmental issues and investigating both indoor and outdoor occupational exposures.

She expects the new standard will be very helpful to building owners and to practitioners already conducting tests in buildings. "I think that the standard provides some guidance as to what is best practice. And I think that because there really haven't been written standards for this -- there have been some documents that have been written by very specific groups, but not a consensus kind of standard -- this kind of brings all of the different thoughts together, from many different perspectives, into one document that provides a general consensus as to what is the basic standard practice for assessing fungal growth in buildings, what are the basic principles that should always be addressed," she said. "It gives that foundation upon which to build a better practice but also builds the groundwork: This is what you should be doing.

"Some of it is common sense. Many people are already performing these basic principles in their everyday practices. I wouldn't say any of this is rocket science or new, but what it does say is that it prevents you from maybe skipping some steps. It makes sure that, if you are going to say, 'My practice in assessing fungal growth in buildings is in accordance with ASTM D7338,' then that sets a bar that you are working though the thought process and the scientific principles addressed in the standard."

Once it was published, the subcommittee had to begin making building owners and building managers aware of it. Rogers distributed a new release about it from Mycometer's booth at the Indoor Air Expo, but the standard was so new that a presentation about it couldn't be ready by the deadline for presentations at the conference. She has upcoming speeches scheduled before an IAQA chapter in California, in Philadelphia this spring, and at the Environmental Information Association's EIA 2011 National Conference & Exposition in Savannah, Ga., March 27-30 (http://www.eia-usa.org/).

She said she is working with training organizations to ensure the standard is incorporated into their curricula.

The subcommittee's other standard, published in 2009, is ASTM D7391-09, Standard Test Method for Categorization and Quantification of Airborne Fungal Structures in an Inertial Impaction Sample by Optical Microscopy. Two other proposed new standards developed by the subcommittee were on ballot at press time: ASTM WK17177, Test Method for Examination of Fungal Structures on Tape Lift Samples by Optical Microscopy, and ASTM WK22872, Practice for Collection of Total Airborne Fungal Spores via Inertial Impaction Methodology. The subcommittee is developing a lot of sampling techniques that will be linked back into the sampling strategy document, tying it all together, which was the plan back when the subcommittee was created, she said.

ASTM standards are influential worldwide, said Rogers, who is also a member of ASHRAE's 62.1 committee. Being involved in developing standards used internationally has been a big part of her career and would be useful to any practitioner because having a voice and being able to see what's going on within your discipline is very important, she said.

ASTM members can vote on drafts and can find out about standards in process whether they attend meetings or not. But by attending, they will find out how much effort goes into standards development -- knowledge that makes the person a better practitioner, she said. "You understand why a standard would be written that way."

This article originally appeared in the April 2011 issue of Occupational Health & Safety.