Beginning 3
- Results
- Summary results
The dry-fog treatment was successful in reducing and maintaining mold at below background levels over the 6-month demonstration period. Figures 21 to 23 show and Table 7 lists the results of air sampling and surface sam- pling at Bldg. 2261. Figures 24 to 26 show and Table 8 lists the results of air sampling and surface sampling at Bldg. 6733. Sections 3.1 and 3.2 give detailed results specific to individual surface and air sampling locations within each building.
Figure 22 shows that the total spore count weighted across all air sampling locations associated with Bldg. 2261 decreased from 64,126 spores/m3 be- fore treatment, to 3,067 spores/m3 at 6 months after treatment. Over this same time period, the outdoor/background total spore count increased from 590 spores/m3 before treatment, up to 19,000 spores/m3 at
6 months after treatment. Simply put, while the outdoor/background total spore count increased 3,120%, the indoor (i.e., treated space) total spore count decreased 95.21%.
Figure 25 shows that the total spore count weighted across all air sampling locations associate with Bldg. 6733 decreased from 556,057 spores/m3 be- fore treatment, to 3,044 spores/m3 at 6 months after treatment. Over this same time period, the outdoor/background total spore count increased from 3,100 spores/m3 to 20,000 spores/m3 at 6 months after treatment.
As the outdoor total spore count increased 545.2 %, the indoor (i.e., treated space) total spore count decreased by 99.45%
Figure 21. Bldg. 2261 Stachybotrys/Chaetomium vs. Stachybotrys/Chaetomium (background).
Figure 22. Bldg. 2261—Total Spores vs. Total Spores (background).
Figure 23. Bldg. 2261—Hyphal Fragments vs. Hyphal Fragments (background).
Table 7. Surface sampling results in Bldg. 2261.
| Fungal Type | Before | After | 1 Month | 3 Month | 6 Month |
| Cladosporium | 6+ | <1 | 0 | 0 | 0 |
| Penicillium/Aspergillus | 0 | 0 | 0 | 0 | 0 |
| Total | very few | very few | very few | 0 | 0 |
Figure 24. Bldg. 6733—Stachybotrys/Chaetomium vs. Stachybotrys/Chaetocmium (background).
Figure 25. Bldg. 6733—Total Spores vs. Total Spores (background).
Figure 26. Bldg. 6733—Hyphal Fragments vs. Hyphal Fragments (background).
Table 8. Surface sampling results in Bldg. 6733.
| Fungal Type | Before | After | 1 Month | 3 Month | 6 Month |
| Cladosporium | 10+ | <1+ | 0 | 0 | 0 |
| Penicillium/Aspergillus | 0 | 2+ | 0 | 0 | 0 |
| Total | very few | very few | very few | 0 | very few |
- Dining facility – Bldg. 2261
- Air sampling
Table 9 lists the results of the air sampling at Bldg. 2261. Each sampling location was allocated a representative number of square feet within the total square footage treated. A summation of the #spores/m3 at each sam- pling location within the building, multiplied by the associated square feet for each sample, divided by the total number of square feet treated, pro- vides a weighted average of the sampling results, which comprises a single value for each fungal type for each building. The efficacy of the treatment is determined by comparing these values to the background levels at the time of each sampling. Values at or below background levels indicate that the treatment and/or removal was (and continues to be) effective.
Table 9. Air sampling results (#spores/m3) for Bldg. 2261.
ID | Associated Area (sq ft) | Fungal Type | Before | After | 1 Month | 3 Month | 6 Month |
| #1 | 2268 | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 19000 | 15000 | 1500 | 170 | 2800 | ||
| Hyphal Fragments | 1300 | 430 | 0 | 0 | 0 | ||
| #2 | 756 | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 48000 | 12000 | 1400 | 480 | 4300 | ||
| Hyphal Fragments | 2000 | 0 | 0 | 0 | 0 | ||
| #3 | 486 | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 110000 | 12000 | 2000 | 2800 | 2500 | ||
| Hyphal Fragments | 2700 | 0 | 0 | 0 | 53 | ||
| #4 | 198 | Stachybotrys/ Chaetomium | 520000 | 0 | 13 | 13 | 0 |
| Total | 530000 | 11000 | 2000 | 2600 | 2800 | ||
| Hyphal Fragments | 5800 | 0 | 0 | 0 | 53 | ||
| #5 | Outdoor/ Background | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 590 | 590 | 3400 | 9000 | 19000 | ||
| Hyphal Fragments | 110 | 110 | 0 | 0 | 0 |
Samples #3 and #4 show an increase in hyphal fragments at the 6-month sampling event (highlighted in yellow). Even though the levels increased (from zero for the previous sampling events), they are still well below the levels before treatment. However, levels are above the background level of zero. Ideally, a future sampling round could potentially determine if this is an increasing trend, or an increase due to activity within the room where Sample #4 was taken, and adjacent to the area represented by Sample #3.
While performing the 3-month sampling event, team members encoun- tered demolition activities in the room represented by Sample #4. Figure 27 shows the debris and the meter reading showing 100% moisture con- tent on the wall surface. The wall was damp to the touch and clearly satu- rated with water. The adjacent room, represented by Sample #3, had re- cently began to leak from the ceiling (Figure 28). It is believed that these changes to the interior environmental/structural conditions played a role in the increased total spore count. However, it should be noted that the background total spore count continued to increase beginning with the 1- month sampling event through the 6-month sampling event, where background was between four and seven times greater than the indoor sample results.
Figure 27. Wall surface moisture content of 100% near Sample Location #4.
Figure 28. Leakage from ceiling piping or roofing.
- Surface sampling
Table 10 lists the results of the surface sampling at Bldg. 2261. Initially all surfaces indicated the presence of mold. Immediately after treatment, only a “very few†total spore count was present at Sample Locations #6 and #7. Sample Location #8 showed < 1+. No surface mold was detected at any surface sample location for the 3-month sampling event. Mold levels at all sample locations remained zero thru the 6-month sampling event.
Table 10. Surface sampling results for Bldg. 2261.
| ID | Fungal Type | Before | After | 1 Month | 3 Month | 6 Month |
| #6 | Cladosporium | 2+ | 0 | 0 | 0 | 0 |
| Penicillium/ Aspergillus | 0 | 0 | 0 | 0 | 0 | |
| Total | very few | very few | 0 | 0 | 0 | |
| #7 | Cladosporium | 2+ | 0 | 0 | 0 | 0 |
| Penicillium/ Aspergillus | 0 | 0 | 0 | 0 | 0 | |
| Total | very few | very few | 0 | 0 | 0 | |
| #8 | Cladosporium | 2+ | <1+ | 0 | 0 | 0 |
| Penicillium/ Aspergillus | 0 | 0 | 0 | 0 | 0 | |
| Total | very few | very few | very few | 0 | 0 |
- Barracks—Bldg. 6733
- Air sampling
Table 11 lists the results of the air sampling at Bldg. 6733. Each sampling location was allocated a representative number of square feet within the total square footage treated. A summation of the #spores/m3 at each sam- pling location within the building, multiplied by the associated square feet for each sample, divided by the total number of square feet treated pro- vides a weighted average of the sampling results, which comprises a single value for each fungal type for each building. The efficacy of the treatment is determined by comparing these values to the background levels at the time of each sampling. Values at or below background levels indicate that the treatment and/or removal was (and continues to be) effective.
Table 11. Air sampling results (#spores/m3) for Bldg. 6733.
ID | Associated Area (sq ft) | Fungal Type | Before | After | 1 Month | 3 Month | 6 Month |
#10 | 1458 | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 110000 | 210000 | 1200 | 430 | 93 | ||
| Hyphal Fragments | 0 | 0 | 0 | 0 | 0 | ||
#11 | 768 | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 1400000 | 100000 | 1100 | 480 | 210 | ||
| Hyphal Fragments | 150 | 0 | 0 | 0 | 0 | ||
#12 | 648 | Stachybotrys/ Chaetomium | 80 | 0 | 0 | 0 | 0 |
| Total | 3400 | 13000 | 3300 | 1200 | 10000 | ||
| Hyphal Fragments | 110 | 53 | 0 | 0 | 0 | ||
#17 | Outdoor/ Background | Stachybotrys/ Chaetomium | 0 | 0 | 0 | 0 | 0 |
| Total | 3100 | 3100 | 8100 | 14000 | 20000 | ||
| Hyphal Fragments | 0 | 0 | 0 | 0 | 0 |
Note that between the 3-month and 6-month sampling events, the Fort Campbell personnel and/or contractor personnel began to renovate the building. It is very likely that ingress and egress of these personnel had some effect on the existing conditions. However, no monitoring or over- sight was in place to account for these differing site conditions. This may explain the drastic increase of total spores for the 6-month sampling event (1200 spores/m3 to 10,000 spores/m3) at Location #12 (basement of the administrative area) in Bldg. 6733, which represents a 733% increase while the background spore count only increased by 42.9%. Despite this drastic increase, indoor levels were only 50% of the background level suggesting continued treatment.
- Surface sampling
Table 12 lists the results of the surface sampling at Bldg. 6733. Initially all surfaces indicated the presence of mold, specifically cladosporium. One month after treatment, only a “very few†total spore count was present at Sample Locations #14 and #16. Three months following treatment, “very few†were reported for Location #14 and no mold spores were present at Locations #15 and #16. Levels appeared to be rising between the 3-month and 6-month sampling events. During this time, the building’s interior changed from an uninhabited space to a space undergoing renovation.
This change in environment, combined with added occupancy and ongoing renovation activities, created varying conditions that could have triggered an increased total spore count. Continued monitoring and sampling could have provided greater insight as to whether this trend would continue. Un- fortunately, the scope of work did not include this continued work.
Table 12. Surface sampling results for Bldg. 6733.
| ID | Fungal Type | Before | After | 1 Month | 3 Month | 6 Month |
| #14 | Cladosporium | 2+ | 0 | 0 | 0 | 0 |
| Penicillium/ Aspergillus | 0 | 0 | 0 | 0 | 0 | |
| Total | very few | very few | very few | very few | very few | |
| #15 | Cladosporium | 4+ | 0 | 0 | 0 | 0 |
| Penicillium/ Aspergillus | 0 | 2+ | 0 | 0 | 0 | |
| Total | 0 | very few | 0 | 0 | very few | |
| #16 | Cladosporium | 4+ | <1+ | 0 | 0 | 0 |
| Penicillium/ Aspergillus | 0 | 0 | 0 | 0 | 0 | |
| Total | 0 | very few | very few | 0 | few |