Discovered Mold -- Now What -- Q&C

Questions & Comments: Discovered Mold -- Now What?
November 25, 2002

Discovered Mold -- Now What? ▪ p1m.com Home ▪ Supply Chain ▪ Mitigation ▪ Loss Recovery Guide with Standards ▪ p1mX-CAT Indexes^SM

Question #1: Please clarify your statement -- "Odds are, if you perform restorative drying -- you will eventually discover mold during the loss site evaluation or drying process." (JB - PA)

Comment #1: The aforementioned statement is meant to reflect pre-loss conditions (i.e., age, design, lack of maintenance, improper maintenance, hidden conditions, infiltration, exfiltration, etc.) of a structure, that could have resulted in mold formation. In addition, if a structure suffered a water loss in the past, the structures owner could have dried the structure improperly themselves, or hired a vendor that lacked the proper drying skills. Resulting in mold formation in hidden areas. And we must not forget, the way our industry dried structures 10 years ago, and the way we dry structures today has changed considerably.

Question #2: Having attended a hands on drying school (i.e., top down drying, structural drying, whole-house drying, etc.) where they flood a house over and over again, that results in no mold formation, I must disagree with your comment -- "Odds are, if you perform restorative drying -- you will eventually discover mold during the loss site evaluation or drying process." (TW - PA)

Comment #2: We at p1m personally feel the hands on drying schools (i.e., top down drying, structural drying, whole-house drying, etc.) are excellent, and everyone who is in the drying business, as well as adjusters should attend one. However, we feel these drying processes have not related building pressure, air velocity, air turbulence, hidden conditions, etc. with cross contamination, which could result in the spread of contaminates to non-contaminated areas.

If we review how structures live and breath, ⁽³⁾ are designed (building sciences), the construction process, and the habits of construction workers during the building process, the aforementioned drying processes should include the containment of wet / moist areas, the use of negative air machines (NAM's), as well as the sealing off of HVAC diffusers (supply and return), or the use of HEPA filters over HVAC diffusers (supply and return).

To better understand our thoughts on the above recommendations, we will relate an experience we encountered in Phoenix Arizona. ⁽¹⁾ Where a Pressure Transducer was used to monitor the air pressure differential within two wall cavities, within two inside walls -- against the air pressure of the room of which the two inside walls are a part of (specific room).

This simple test included the opening of the door within the specific room, the opening of the door in an adjoining room, the opening of the door in a mechanical equipment room with block fire walls, and the opening of the main entrance door of the structure. All of which produced a pressure differential between the atmosphere within the specific room and the wall cavities within the interior walls of the specific room.

Now, let's review the top down drying, structural drying, whole-house drying, etc. processes, where turbo fans (air-movers) that produce up to two feet per second of air are placed every three feet:

Could this much air pressure and air velocity cause cross contamination? And when holes are drilled within wall cavities and turbo fan attachments are used to push or force two feet per second of air within these wall cavities – could contaminates be distributed throughout a structure?

Yes, based on the Pressure Transducer example mentioned above and the principle of CFM in = CFM out.

Could this much air pressure force contaminates within a structures HVAC system?

Yes, based on air velocity, as well as CFM in = CFM out.

Drying standards of the future need to clearly address drying processes with respect to the distribution of contaminates, as an example:

-- "appropriate provision shall be implemented prior to the drying process to prevent cross contamination within a structure,"
and please note the word shall, which signifies mandatory.

Until then, restoration vendors, facility managers, property owners and adjusters can reference the 'Loss Recovery Guide with Standards' (LRGS) Sections 7.5.c and 7.5.d:

(LRGS: 7.5.c) "Every effort should be made to prevent cross-contamination during mitigation or remediation. Already cleaned, disinfected and sanitized areas should be posted as cleaned and sanitized. The prevention of cross-contamination should include persons (foot traffic), clothing, equipment, tooling, chemical, material packaging and air infiltration through HVAC systems."

(LRGS: 7.5.d) "When working in contaminated areas, the contaminated area should be closed (sealed) off by means of vapor barrier to limit the possibility of airborne contamination. HVAC systems should be closed off or shut down from the balance of the structure until the mitigation or remediation process is completed."

(LRGS: 1.6) "(Should: Recommended, but industry or individual experience can take precedence."

Now let's review the construction process, and the habits of construction workers during the building process:

No.1) How many building sites follow the rules within the Wood Handbook: wood as an engineering material ⁽²⁾ -- published by the U.S. Forest Products Laboratory: USDA Forest Services, where:

a) building materials are properly stored on a building site: "Supports under such packages (lumber) are useful to prevent wetting from mud and ground water and should elevate the package at least 150 mm (6 inches) off the ground. The packages (lumber) should also covered with plastic tarpaulins for protection from rain."

b) wood framing is allowed adequate time to dry, prior to enclosure (gypsum board): "… Framing lumber, even thoroughly air-dried stock, will generally have a moisture content greater than that recommended when it is delivered to the building site. If carelessly handled in storage at the site, the lumber can take up more moisture. Builders can schedule their work so an appreciable amount of drying can take place during the early stages of construction. This minimizes the effects of additional drying and shrinkage after completion. When the house has been framed, sheathed, and roofed, the framing is so exposed that in time it can dry to a lower moisture content than would ordinarily be expected in yard-dried lumber. The application of the wall and ceiling finish is delayed while wiring and plumbing is installed. If this delay is about 30 days in warm, dry weather, framing lumber should lose enough moisture so that any additional drying in-place will be relatively unimportant. In cool, damp weather, or if wet lumber is used, the period of exposure should be extended." While, the Wood Handbook: wood as an engineering material goes onto state: "Closing of the house and using the heating system will hasten the rate of drying."

When reviewing (a) and (b) above, one would think that all homes are thoroughly dried per the Wood Handbook, and that all builders use moisture meters on every project and record their moisture readings before framing lumber is enclosed with gypsum board. Therefore, we should presume that all builders will delay the installation of gypsum board on at least one side of a framed wall for 30 days in warm, dry weather. Moreover, builders would also extend this 30 day period should the weather be cool and damp!

No. 2) Most building contractors maintain a considerably clean job site during the construction process, however:

a) does the building contractor use a HEPA vacuum to clean up dirt, wood dust, gypsum dust, etc., or do they use a broom to cleanup dirt, wood dust, drywall, etc. Leaving the question, if they use a broom, do they use an air scrubber?

a.1) Since the use of a broom to clean up dirt, wood dust, gypsum dust, etc. creates static dust that will cling to framing lumber, do building contractors HEPA vacuum and/or chem-sponge framing lumber prior to the installation of gypsum board?

b) Now lets review construction workers habits at building sites: On hot sunny days, or on rainy days, workers will generally have their coffee breaks and lunch within the framed structure. And when food, or beverages spill on the plywood floor, will the workers cleanup the spilled food or beverages with soap and water? And, should a worker cut his finger and blood drips on the plywood floor, will the blood be properly removed and the area disinfected? And of course, construction workers never urinated within a structure while it was being built?

Food for Thought: When considering static dust (i.e., dirt, wood, gypsum, etc.) we should relate dust to kindling – as in starting a fire. Several years ago, one of the p1m staff tried to grow mold on a piece of dimensional lumber using moisture and heat within a dark area, and mold would not produce on the 2x4. However, when we added a mixture of dust (i.e., dirt, wood, gypsum, etc.) to the 2x4, we had germination almost overnight. In essence, we created a real world situation (e.g., mold - kindling).

Question # 3: Why is the insurer to be blamed for mold problems? – does not respond in a timely fashion, or limits drying contractor in scope, does not understand the problem? (EV – AZ)

Comment # 3: In some instances, all of the above could apply. In addition, some adjusters do not understand the drying process, or how to relate the drying process to the built environment, while this also applies to some drying vendors. However, over the past year, adjusters have been attending water drying schools and mold remediation classes in record numbers, and communication between adjuster and vendor is improving in some markets.

Question # 4: Are drying contractors not understanding what must be done to dry a structure, do most know, but are limited by adjusters input? Since everything can not be explained in a short article, I asked our water loss manager the above question, and his response was: we still have some adjusting offices stating do what you have to do, but do not remove the carpet until the adjuster sees it in a few days. (EV – AZ)

Comment # 4: To thoroughly dry a structure, we must base our drying principles around psychrometrics. However, all the psychrometrics in the world will not dry a structure within an expedient time frame to prevent mold formation, unless we relate psychrometrics to the built environment, which is most pertinent in hidden areas (e.g., cavities).

For the past year, p1m has been preaching and teaching that we must dry to the built environment, ⁽³⁾ resulting in 98% of those who attended our classes to understand this process.

With respect to leaving the carpet in place until the adjuster can inspect it: We recommend professional judgement. Meaning, if a vendor feels the carpet and pad needs to be pulled to lessen further damages, by all means, as professionals, we should pull the carpet. However, as professionals, we must openly communicate with adjusters, and utilize digital photographs and digital videos. Moreover, remove the carpet in a fashion that does not cause further damages, as well as save the carpet and pad in a fashion that does not cause further damages.

Food for Thought: Having done business with, and provided seminars for hundreds of adjusters, we must state, we have never met an adjuster who gets up in the morning, looks themselves in the mirror and says: I think I will go out and screw a vendor or property owner today. This is just not the case. However, we view our industries past practices of invoicing without thorough documentation, as well as the lack of an in-depth explanation of the loss and drying processes as one of the primary reasons.

In our seminar, p1m · Loss-Mitigation: Preventing Mold, we review why adjusters and property owners would dictate the loss-mitigation scope of work:

· lack of loss-mitigation guidelines or standards knowledge,

· lack of built environment knowledge,

· lack of building code knowledge,

· lack of loss site knowledge,

· does not understand drying,

· lack of IAQ knowledge,

· lost trust with vendor,

· excessive costs

When reviewing the aforementioned reasons why adjusters and property owners would dictate the loss-mitigation scope of work, we must understand that these reasons are also dualistic, meaning, the adjuster or property owners could be questioning the vendors lack of knowledge as well.

Question # 5: Due to the heightened awareness of indoor air quality, do you feel the use of air scrubbers, high pressure drying equipment ⁽⁴⁾ and containment will become standard procedure in the future? (BW – CA)

Comment # 5: As stated in Comment #2 above, we do not see an alternative if we want to protect our customers from potential contaminates, or limit our liability of a potential law suit. Moreover, the use of high pressure drying equipment with an inline HEPA filter attachment could be the only alternative to drying wet / moist cavities when contaminates are present, furthermore, minimizing ensuing loss expenses.

Footnotes:

Strategies For Conducting Meaningful Microbial IAQ Investigations (seminar) · American IAQ Council -- www.iaqcouncil.org/microbial-strategies.htm

Wood Handbook: wood as an engineering material -- published by the U.S. Forest Products Laboratory: USDA Forest Services: Chapter 12, pages 12-18, 12-19 -- www.fpl.fs.fed.us/pubs.htm

p1m · Loss-Mitigation: Preventing Mold (seminar) -- Publication: Drying to the Built Environment

High pressure drying equipment, as manufactured by Dri-Eaz Products, Inc. -- www.dri-eaz.com and Injectidry Systems, Inc. -- www.injectidry.com

Recommended Changes to Discovered Mold – Now What?

Section 10.1.6 (d):

~~The inspection of hidden areas is best performed with the aid of a boro-scope.~~

Boro-scopes will not detect mold spores that could be present within hidden cavities, while the use of a boro-scope could aid visual inspections when searching for visible mold formation. (LRGS: 1.6) "Could: possible, maybe, all venues should be evaluated."