Routine Air Sampling for Mold Not Recommended

[Guest guest]

Below is the section discussing air sampling for mold in the draft NIOSH Alert: "Preventing Occupational Respiratory Disease from Exposures caused by Dampness in Office Buildings, Schools, and Other Nonindustrial Buildings"

"Is Air Sampling for Mold Necessary?

NIOSH does not recommend routine air sampling for mold in damp building evaluations because air concentrations of molds or spores cannot be interpreted with regard to health risk and they are highly variable over time. Instead, NIOSH encourages detection by thorough visual inspections and detection via musty odors. Building consultants can sometimes identify sources of dampness with moisture meters and infrared cameras. In cases where there is no visible sign of dampness, destructive inspections may be necessary to find hidden water intrusion or mold. Destructive inspections involve removal of the surfaces of building materials, such as to inspect wall cavities, under floor coverings, or behind wall coverings in order to determine hidden sources. In certain conditions, air sampling may aid in the determination of hidden mold; this is discussed further in Chapter 6 and Chapter 10 of the AIHA publication “Recognition, Evaluation, and Control of Indoor Mold†[AIHA 2008]. Building consultants often recommend and perform “clearance†air sampling after remediation work has been completed in an attempt to demonstrate that the building is safe for occupants. However, NIOSH does not recommend this practice, as there is no scientific basis for the use of air sampling for this purpose. No consistent exposure-response relationships have been demonstrated for specific bioaerosol measurements which allow reassurance of building occupants that an indoor environment is safe or that a health hazard continues after remediation. Once remediation is completed (moldy and damaged materials removed; musty odors no longer evident), the best evidence that the building is safe may be that workers or occupants no longer experience building-related symptoms. Unfortunately, even if most workers or occupants experience improvement in their symptoms, and new workers or occupants remain free of building-related symptoms, some with allergic conditions may not notice an improvement. Such individuals may have to avoid the building even after an otherwise successful remediation because their immune systems may continue to react to very small amounts of substances to which they are allergic."

That's what the NIOSH document actually says. Testing for mold spores cannot be used to determine that a building is safe for occupants.

Steve Temes

[Guest guest]

It should say, "

Building consultants often recommend and perform “clearance†air sampling after remediation work has been completed in an attempt to demonstrate that the building is safe for occupants. However, NIOSH does not recommend this practice, as there is no scientific basis for the use of air sampling for this purpose. There is a scientific basis for sampling before and after certain remediation projects if one is seeking to establish that the air quality improved from the endeavor.

[Guest guest]

Sharon,

I agree that the wording should not make it seem that sampling isn't a very useful tool for assessing presence or absence of particulate contaminants of microbial origin for investigation and mold remediation purposes. It IS a very useful tool for indirectly assessing "microbial cleanliness". The point they are making is that it is not possible to assess health risk on the basis of spore counts -- only the presence or (relative) absence of these contaminants.

That's what the document is trying to say but, evidently, it is being misunderstood by people who are reading it. The authors are specifically acknowledging that sensitized people can react to contaminants (volatile or 'non-spore' particulate) that remain after remediation, even at very low concentrations. Testing the air for spores, therefore, will not tell you whether they will react or not when they return after the place has been cleaned.

I think the problem is that clean is equated with safe by people who don't understand how mold makes people ill. "Testers" are hired by uninformed clients to test for the purpose of determining health risk, so that's what they try to do -- even though you can't do that.

Steve Temes

It should say, "

Building consultants often recommend and perform “clearance†air sampling after remediation work has been completed in an attempt to demonstrate that the building is safe for occupants. However, NIOSH does not recommend this practice, as there is no scientific basis for the use of air sampling for this purpose. There is a scientific basis for sampling before and after certain remediation projects if one is seeking to establish that the air quality improved from the endeavor.

[Guest guest]



Steve

This excerpt gives different conclusion if read by different stakeholders who have different objectives and considering our joint current debate of just one small group of EH it may show how poorly worded the NIOSH statement is. I accept there is a debate because NIOSH then go on to refer to Chapter 6-10 of AIHA but readers of NIOSH or facility managers will not have this and nor do I.The caveat actually asks the reader to become an investigator and interpreter of science data to which there are no standards and therefore isn't in my opinion a guide at all.

I take the same paragraph as you and interpret as a different stakeholder:

Building and restoration contractor .

“I used my two pin moisture meter and cannot detect any moisture in any surface from the flood event you had last year or which travelled through interstitial cavities so I must do intrusive investigationâ€

“No need for EH or air sampling, NIOSH recommend visual and odour detection as best investigation technique so we may need to gut the building to find all the mould growthâ€

“No need for EH because they can’t tell us anything of any use, they can’t tell us if its safe or not by their expensive sampling and we all have eyes and nose don’t weâ€

“NIOSH recommend we pull up floors and open wall and ceiling cavities to detect hidden mould. Do you want to go against NIOSH or pay up?

Facility Manager

“There is no odour or visible mould and as mould exposure cannot be measured as a health risk why should I investigate furtherâ€

“We opened up a wall under a leak and found nothing, are we supposed to open up every cavity and gut the building?

“We found one small area of mould behind a skirting board of a gyprock wall and just cleaned the skirtingâ€

“We don’t need the expensive containment and negative pressure you specified, even if there is spores release there is no repercussion according to NIOSH as all we have to do is remove visible mould not sporesâ€

“There is no mold problem because we have no visible mold and we can’t smell anything other than pineapple due to the air fresheners we useâ€.

The employer or landlord

“Why should I undertake mold decontamination, NIOSH state there is no known correlation between levels of exposure and safetyâ€

“I’m not interested in your health complaint, NIOSH says you should leave the building and live-work elsewhere because you are sensitiveâ€

The lawyer

“My client, your tenant/employee lived and worked in the property with exposure to mold which according to the World Health Organisation triggers asthma and other may cause other diseasesâ€but you failed to investigate using techniques recognised and preferred by WHO.

“Although there are no safe levels of exposure that doesn’t mean exposure is safe, indeed there are no safe levels of exposure to lead bullets in the brain, how did you assess what the exposure to my client may be or was other than waiting for them to get sick and move out?

If the ambient air total spore count was 1000 and the property had a spore count of 50,000 with 90% of the spores identified inside undetectable in ambient, could that be seen as a possible health hazard which should have been identified?

“Is it true that the chemical mycotoxins, often released from live or dead mould on invisible sub micron particulates is a major health hazard to susceptible people but by following NIOSH you did not assess this risk?

Environmental Hygienist

“No sampling may be required but you will have to look at another document Chapter 6 -10 of AIHA†. What you have never heard of AIHA, they are ……….. you’ve lost haven’t you! NIOSH have made a blanket statement with a small caveat for their benefit by expecting people to investigate industry discussions. This is not a guide for reducing health hazards but a licence for ignoring invisible mold and uncontrolled spore release which the world recognises is a health risk.

Conclusion.

Is the NIOSH document supposed to be a useable reference to “Preventing disease†or has it been designed to cause confusion and debate?

As mould hazards can be invisible and odourless, the testing of contamination albeit perhaps flawed must be seen in legal and risk reduction terms more suitable and practical than waiting for people to get sick.

Getting sick is usually associated with loss of performance at work, absenteeism and increased strain on medical assistance so financially there is a big carrot for sampling.

Is mold sampling accurate as a guide to what is safe or what is not? Yes a guide but not a standard.

I can’t believe NIOSH recommend not using something which can assist in the identification of a hazard because it may provide false positives or negatives. They accept similar shortfalls in a host of other risk assessments.

Regards

Jeff

London

-----Original Message-----From: iequality [mailto:iequality ]On Behalf Of AirwaysEnv@...Sent: 13 July 2011 14:32To: iequality Subject: Routine Air Sampling for Mold Not Recommended

Below is the section discussing air sampling for mold in the draft NIOSH Alert: "Preventing Occupational Respiratory Disease from Exposures caused by Dampness in Office Buildings, Schools, and Other Nonindustrial Buildings""Is Air Sampling for Mold Necessary? NIOSH does not recommend routine air sampling for mold in damp building evaluations because air concentrations of molds or spores cannot be interpreted with regard to health risk and they are highly variable over time. Instead, NIOSH encourages detection by thorough visual inspections and detection via musty odors. Building consultants can sometimes identify sources of dampness with moisture meters and infrared cameras. In cases where there is no visible sign of dampness, destructive inspections may be necessary to find hidden water intrusion or mold. Destructive inspections involve removal of the surfaces of building materials, such as to inspect wall cavities, under floor coverings, or behind wall coverings in order to determine hidden sources. In certain conditions, air sampling may aid in the determination of hidden mold; this is discussed further in Chapter 6 and Chapter 10 of the AIHA publication “Recognition, Evaluation, and Control of Indoor Mold†[AIHA 2008]. Building consultants often recommend and perform “clearance†air sampling after remediation work has been completed in an attempt to demonstrate that the building is safe for occupants. However, NIOSH does not recommend this practice, as there is no scientific basis for the use of air sampling for this purpose. No consistent exposure-response relationships have been demonstrated for specific bioaerosol measurements which allow reassurance of building occupants that an indoor environment is safe or that a health hazard continues after remediation. Once remediation is completed (moldy and damaged materials removed; musty odors no longer evident), the best evidence that the building is safe may be that workers or occupants no longer experience building-related symptoms. Unfortunately, even if most workers or occupants experience improvement in their symptoms, and new workers or occupants remain free of building-related symptoms, some with allergic conditions may not notice an improvement. Such individuals may have to avoid the building even after an otherwise successful remediation because their immune systems may continue to react to very small amounts of substances to which they are allergic."That's what the NIOSH document actually says. Testing for mold spores cannot be used to determine that a building is safe for occupants.Steve Temes

[Guest guest]

Steve,

You are about the best I know at this kind of stuff. How would you word it differently to accurately convey the intent meant, "Mr. Terms"?

Sharon

Sharon,I agree that the wording should not make it seem that sampling isn't a very useful tool for assessing presence or absence of particulate contaminants of microbial origin for investigation and mold remediation purposes. It IS a very useful tool for indirectly assessing "microbial cleanliness". The point they are making is that it is not possible to assess health risk on the basis of spore counts -- only the presence or (relative) absence of these contaminants.That's what the document is trying to say but, evidently, it is being misunderstood by people who are reading it. The authors are specifically acknowledging that sensitized people can react to contaminants (volatile or 'non-spore' particulate) that remain after remediation, even at very low concentrations. Testing the air for spores, therefore, will not tell you whether they will react or not when they return after the place has been cleaned.I think the problem is that clean is equated with safe by people who don't understand how mold makes people ill. "Testers" are hired by uninformed clients to test for the purpose of determining health risk, so that's what they try to do -- even though you can't do that.Steve Temes

Sharon Noonan Kramer

[Guest guest]

I think the NIOSH authors went out of their way to de-emphasize air sampling for clearance testing because "clean" gets too easily confused with "safe". A low spore count does not translate into "it's safe for everyone to return".

What they failed to do is explain how mold testing can be useful. As Jeff pointed out, the vague reference to chapter numbers in an expensive, esoteric book does not convey the value of sampling as a tool in performing investigations/assessments or its value in professional mold remediation projects (pre- or post-).

All they need to do is clarify that mold testing used for determination of presence/absence can be a surrogate indicator of microbial cleanliness, and that mold testing is not a health risk assessment. As the NIOSH Alert clearly explains, there are contaminants other than spores to be concerned about inside a water-damaged building. You can't just test for spores and say everything is OK.

Steve Temes

Re: Routine Air Sampling for Mold Not Recommended

Steve,

You are about the best I know at this kind of stuff. How would you word it differently to accurately convey the intent meant, "Mr. Terms"?

Sharon

Sharon,

I agree that the wording should not make it seem that sampling isn't a very useful tool for assessing presence or absence of particulate contaminants of microbial origin for investigation and mold remediation purposes. It IS a very useful tool for indirectly assessing "microbial cleanliness". The point they are making is that it is not possible to assess health risk on the basis of spore counts -- only the presence or (relative) absence of these contaminants.

That's what the document is trying to say but, evidently, it is being misunderstood by people who are reading it. The authors are specifically acknowledging that sensitized people can react to contaminants (volatile or 'non-spore' particulate) that remain after remediation, even at very low concentrations. Testing the air for spores, therefore, will not tell you whether they will react or not when they return after the place has been cleaned.

I think the problem is that clean is equated with safe by people who don't understand how mold makes people ill. "Testers" are hired by uninformed clients to test for the purpose of determining health risk, so that's what they try to do -- even though you can't do that.

Steve Temes

Sharon Noonan Kramer