The Effect of Ozone as a Biocide in two Mold Contaminated Houses in the Katzie First Nation Community
May 03, 2001
Table of Contents
1.0 EXECUTIVE SUMMARY 1
2.0 INTRODUCTION 1
3.0 SITE DESCRIPTION 2
4.0 SITE VISIT 2
5.0 SAMPLING and ANALYSIS 2
5.2 Sampling Materials (Surface) 3
5.3 Sampling Methods 3
5.3 Sampling Methods 3
5.4 Analysis 4
5.4.1 Analytical Profiles 4
5.4.2 Total Fungal Count 4
6.0 EVALUATION of FINDINGS 6
6.1 Data Interpretation and Air Quality Standards 6
7.0 SUMMARY of FINDINGS and RECOMMENDATIONS 6
8.0 QUALIFICATIONS 7
8.1 Competence of the Inspector 7
9.0 REFERENCES and SUPPORTING DOCUMENTATION 8
Reference No. 2 8
Reference No. 3 8
Reference No. 4 8
Reference No. 5 8
Reference No. 6 8
10.0 LIMITATIONS and USE of REPORT 9
1.0 EXECUTIVE SUMMARY
A Site Inspection was conducted May 1, 2001 on two houses located in the Katzie First Nation community near Maple Ridge , BC. The purpose of the inspection was to evaluate the effect of ozone as a biocide in the two houses. While both were suspected of having problems relating to fungi (mold and yeasts), only the second house showed signs of visible mold . The Ozone was administered by a technician of Medallion Healthy Homes Ltd. according to their published methodology
A Visual Inspection was conducted in the interior of the houses. Surface and air samples were collected before and after ozonation in the houses and submitted to a lab for analysis.
It has been established through consultation with government officials that no standards exist at this time regarding what are "Acceptable Limits" for the mould and yeast counts which are
analyzed from the surface samples.
It is our opinion that the results noted in this report would indicate that the surface and air samples taken after ozonation show a relative absence of active fungal spores present and are considered sufficiently decontaminated to be adequate for the occupants to reoccupy the home.?
2.0 INTRODUCTION
Medallion Healthy Homes Ltd. engaged TEKNIKA ENVIRONMENTAL CONSULTANTS to conduct an investigation into the effect of ozone as a biocide in two mold contaminated houses. Medallion Healthy Homes Ltd. through the use of proprietary ozone generation equipment provides a service whereby indoor air is purified . Using this equipment, Medallion has developed a methodology in which very high levels of ozone are introduced into a vacated and locked out home, office, boat, etc. Once the ozonation phase is completed, the residual ozone is extracted and the air tested to ensure that any remaining ozone is at a level acceptable for human occupation. The residents of the subject properties had complained of problems in the homes, which they felt was making them feel sick. These homes and their occupants would fall within the commonly accepted definition of a " Sick House Syndrome ".
Sick House Syndrome , also known as " Sick Building Syndrome" is a general category for a number of ailments, allergies, and complaints, all due to some physical aspect of the building. It is usually related to the existence of low concentrations of pollutants, synthetic irritants, fungi or other microorganisms, that are sufficient factors to cause reactions in a number of the building's occupants. Even extremely low concentrations of several pollutants or irritants is sufficient to incapacitate certain sensitive individuals.
3.0 SITE DESCRIPTION
The subject sites are one story bungalow type single family homes located in a residential area in the Katzie First Nation community near Maple Ridge in British Columbia. They are of wood frame construction . The first house was built on a concrete perimeter sealed crawlspace foundation. The second house had an unsealed crawlspace which the owner described as having a severe water problem. The first house is heated with a forced air furnace located off the kitchen. The second house has electric heat. The roof of the second house shows signs of water damage and is considered to be leaking. Therefore, the roof leak combined with the water in the crawlspace increases the possibility of water entering the interior of the home.?
4.0 SITE VISIT
The visit was conducted on May 1 , 2001. A visual site inspection was conducted targeting obvious areas of mold contamination. The visual inspection of the first home did not reveal any apparent areas of active mold growth . The visual inspection of the second house revealed numerous areas (totaling over 32 square feet) of active mold growth. Microscopic examination of contact samples taken from the walls confirmed the presence of fungal material. Surface swabs and air sample were taken prior to ozonation.
A Medallion Healthy Homes Ltd. Technician prepared the two homes for ozonation following their approved methodology. The ozonation was conducted for a four hour period The ozone was then extracted and had dropped to 0.05 ppm at the time the second sets of surface swabs and air samples were taken.
The relative humidity (RH) during the test was recorded as:?
House # 1 interior 37%, exterior 56%
House # 2 interior 76% exterior 79%
5.0 SAMPLING and ANALYSIS
5.1 Introduction to Sampling
To the qualified Inspector, gross contamination of building materials is usually self-evident. It is often useful scientifically to take representative samples to demonstrate the presence or absence of elevated levels of microorganisms and potentially correlate these levels throughout the structure. In this case, both Air Sampling and Surface Sampling were used, for this investigation.
Two 10 square centimeter sterile templates were applied to the interior walls of both houses. The templates were swabbed prior to the application of ozone (Pre-Ozonation) and also after treatment (Final) .
It has been established through consultation with government officials that no standards exist at this time regarding what are "Acceptable Limits" for the mould and yeast counts which are
analyzed from the surface samples.
NOTE: The Person taking, packaging and transporting samples of suspected mould contaminated substances (Marshall L. Lowen) is a person with Transportation of Dangerous Goods (TDG) certification and the samples were transported under the TDG regulations as a diagnostic specimen as required in Appendix B of the "Recommended Interim Health & Safety Guidelines for Protection of Workers During Mould Remediation and Clean-up in Residential Homes" - Health Canada - May 1998
5.2 Sampling Materials (Surface)
(a.) STARswab Microorganism Collection and Transport System
(b.) Ice pack Bag for transport
(c.) Personal Protective Equipment
5.2 Sampling Materials (Air)
(a.) Prepared Culture Media Settle Plates
(b.) Zip-lock plastic bags
(c.) Ice pack Bag for transport
(d.) Personal Protective Equipment
5.3 Sampling Methods
AIR
1. Record sample information and start time on lid of Settle Plate.
2. Take lid off Settle Plate and expose to atmosphere.
3. After allotted time, replace lid, tape shut and record finish time.
4. Record information on Chain of Custody sheet
5. Place Settle Plate in zip-lock bag and place in ice pack bag for transport to lab
5.3 Sampling Methods
SURFACE
1. Attach and label a sterile 100 sq. cm template to surface to be sampled
2. Peel open sterile swab pack
3. Remove and discard plug from tube
4. Remove swab from the tube and gently swab the template area thoroughly, using a rolling motion with the swab
5. Replace swab in the tube and push in plug to seal
6. Record sample information on the label and Chain of Custody sheet
7. Place tube in ice pack bag for transport to lab
5.4 Analysis
5.4.1 Analytical Profiles
The appropriate analytical parameters should be carefully considered when doing an indoor environmental microbiological survey. Following is the analytical profile used for the evaluation of the Settle Plate and swab samples.
The following results are from analysis conducted according to The Canadian Health Protection Branch Method MFHPB-22
5.4.2 Total Fungal Count
SAMPLE IDENTIFICATION?
YEAST (CFUs) MOULD (CFUs)
House # 1
#1001 - Outside (Pre-Ozonation) 6 15
01/05/01 Settle plate
#1002 - Inside (Pre-Ozonation) <1 20
01/05/01 Settle Plate
#1003 - Crawlspace (Pre-Ozonation) <1 360
01/05/01 Settle Plate
#1004 - Interior Wall (Pre-Ozonation) <1 120
01/05/01?
#1005 - Outside (Final) <1 52
01/05/01 Settle Plate
#1006 - Inside (Final) <1 14
01/05/01 Settle Plate
#1007 - Crawlspace (Final) <1 75
01/05/01 Settle Plate?
#1008 Interior Wall (Final) <1 2
01/05/01 Swab
SAMPLE IDENTIFICATION?
YEAST (CFUs) MOULD (CFUs)
House # 2
#2001 - Outside (Pre-Ozonation) 4 38
01/05/01 Settle Plate
#2002 - Inside (Pre-Ozonation) 3 9
01/05/01 Settle Plate
#2003 - Attic (Pre-Ozonation) 2 24
01/05/01 Settle Plate
#2004 - Bedroom Wall (Pre-Ozonation) 30 <1
01/05/01 Swab
#2005 - Attic (Final) <1 8
01/05/01 Settle Plate
#2006 - Inside (Final) <1 12 (see Note 2 )
01/05/01 Settle Plate
#2007 - Outside (Final) <1 42
01/05/01 Settle Plate
#2008 - Bedroom Wall (Final) <1 <1
Note: < = Less than
Note 2: This number of 12 CFUs could most likely be attributed to the introduction of outside air when ventilating to evacuate the high concentrations of ozone from the home.
CFU - Colony Forming Units, a unit of measurement used in analysis of samples for moulds and yeasts
5.5 Safety Precautions
Microbial growth on building materials is easily aerosolized by physical activity. All sampling of this nature should be done subsequently to any air sampling. Any air samples collected after surface sampling will likely be skewed due to bioaerosols aerosolized from the sampling event.
1. Caution should be exercised when collecting bulk or surface samples in occupied areas. If this type of sampling is to be done, potential exposures to occupants should be addressed and appropriate controls carried out if necessary.
2. The sample collector should avoid coming in contact with any biological material. Proper Personal Protective Equipment is necessary.
6.0 EVALUATION of FINDINGS
6.1 Data Interpretation and Air Quality Standards
There are no specific regulations governing surface microbiological contamination or airborne microbiological contaminants in indoor air (bioaerosols). This is in part due to the many variables involved with sampling for microorganisms, dramatic fluctuations in background levels of microorganisms, lack of agreement between researchers about what constitutes a "problem situation" and an overall lack of industry experience in interpreting microbiological laboratory data. Therefore, it is critical that the Inspectors be able to combine experience and knowledge of microbiology to evaluate laboratory results of samples collected from interior locations.
The New York Department of Health has sponsored the document "Guidelines on Assessment and Remediation of Stachybotrys atra in Indoor Environments" which is referenced in this report.
These guidelines contain numeric standards for bulk material samples only. Those containing Stachybotrys in excess of I colony-forming unit per gram should be remediated. Again, there are no standards for surface swab samples. Spore counts for molds will include all species of moulds and not just those targeted such as Stachybotrys, Penicillus and Aspergillus.
It has been established through consultation with government officials that no standards exist at this time regarding what are "Acceptable Limits" for the mould and yeast counts which are
analyzed from the surface samples.?
In the case of this investigation a comparison of "Before" and "After" findings are examined.
7.0 SUMMARY of FINDINGS and RECOMMENDATIONS
In examining the laboratory results of swabs and air tests taken from the mold contaminated wall we find a significant reduction in CFU's after ozonation (see 5.4.2 Total Fungal Count )
It is our opinion that the results noted in this report would indicate that the samples taken after?
ozonation show a substantial reduction and in most cases a relative absence of active fungal spores present and these houses are considered sufficiently decontaminated to be adequate for the occupants to reoccupy the homes.?
We recommend that the interior of the homes be vacuumed and cleaned using a HEPA type vacuum to ensure the complete removal of microscopic debris that might be allergenic to the occupants.
We also recommend that although the homes might be considered "Decontaminated", prevention of future microbial contamination cannot be assured unless further steps are taken such as:
a) Avoiding the conditions that led to past contamination
b) Using material that are not susceptible to biodeterioration?
c) Applying compounds that suppress vegetative bacterial and fungal growth
8.0 QUALIFICATIONS
8.1 Competence of the Inspector
TEKNIKA ENVIRONMENTAL CONSULTANTS (TEC) and its Senior Consultant, Marshall L. Lowen, possess knowledge through an appropriate combination of formal education, skills, experience and training to provide a technically sound and rational inspection of buildings contaminated with moulds and fungi. TEC has completed many projects involving contaminated sites and the identification and handling of toxic and hazardous materials. TEC_s projects for contaminated sites have typically included historical reviews, field surveys selection, costing and specification of cost-effective treatment options, field supervision, audits, as well as other consulting services. TEC through its associates provides full environmental, occupational safety & health and chemical analysis services to clients for initial assessments of contamination, design of remediation programs, field supervision and monitoring for remediation sites.
NOTE:
TEKNIKA ENVIRONMENTAL CONSULTANTS is a Canadian Aboriginal Company that is 100% Aboriginal owned and controlled. It is registered on Indian and Northern Affairs Canada's Aboriginal Supplier's Inventory.
ASSOCIATIONS:
Canadian Aboriginal Science and Technology Association (CASTS)
American Indian Science and Engineering Society (AISES)
Air and Waste Management Association (AWMA)
Environmental Assessment Association (EAA)
National Environmental Health Association (NEHA)
Mr. Lowen has training education and knowledge in a number of technical areas relevant to the subject site including:
(a) Building Sciences, Construction Practices and Standards
(b) Indoor Air Quality (IAQ)
(a) Representative Sampling Techniques
(d) Remediation and Preventive Maintenance of Fungal Contaminated Buildings
(e) Biology of Fungi
(I) Environmental Control of Contamination caused by microbial overgrowth
(g) CMHC Indoor Air Quality Investigation
(h) Other areas of environmental microbiology
9.0 REFERENCES and SUPPORTING DOCUMENTATION
Reference No. I
New York City Dept of Health, NY City Human Resources Administration, and Mount Sinai - Irving J. Selikoff Occupational Health Clinical Center. - Guidelines on Assessment and remediation of Stachvbotrvs atra in indoor environments.
New York, NY (1993)?
Reference No. 2
First Nations Environmental Health Services, Medical Services Branch, Health Canada, May 1998 -
Recommended Interim Health & Safety Guidelines for Protection of Workers During Mold Remediation
and Clean-up in Residential Homes
Reference No. 3
Aerotech - Kalmar Laboratories, September 1998 -
IAQ Compendium on Fungi
Reference No. 4
Aerotech - Kalmar Laboratories, September, 1998 -
IAQ Data Interpretation and Air Quality Standards
Reference No. 5
Janet Macher, Sc.D., M.P.H. ACGIH (1999)
Bioaerosols: Assessment and Control
Reference No. 6
Daniel Molleker and Daniel O'Connell (2000)
The Medallion Solution
10.0 LIMITATIONS and USE of REPORT
This report was prepared by TEKNIKA ENVIRONMENTAL CONSULTANTS (TEC) for the exclusive use of Medallion Healthy Homes Ltd. (The Client) and is intended to provide The Client with an assessment of the state of mould contamination of the subject site. The material in this report reflects TEC'_s best
judgment considering the information available to TEC at the time of preparation. Any use that a third party makes of this report, or any reliance on or decisions to be made on it, are the responsibility of such third parties. TEC accepts no responsibility for damages, if any, suffered by a third party as a result of decisions made or actions based on this report.
The scope of work for this project was limited to a Site inspection, along with sampling and analysis, is to confirm and delineate, or to demonstrate the absence of fungal contamination prior to and following decontamination of the subject property. No other testing or analysis other?
than those contained in this report were conducted at the site.
This report is based on data and information collected during the investigation conducted by TEC and is based solely on the site conditions of the property at the time of the site inspection, supplemented by data obtained by TEC , as described in this report. Due to possible variations in building practices and site activities that may have existed at this site, there may be localized zones of contamination that were not detected or observed during this inspection.
In evaluating the property, TEC has relied in good faith on information provided by the individuals and Companies noted in the report. We accept no responsibility for any deficiency, misstatements, or inaccuracy contained in this report as a result of omissions, misrepresentation, or fraudulent acts of others involved.
If new information is discovered in future work, including excavations, renovations, remediation, or other studies, TEC should be requested to re-evaluate the conclusions of this report, and provide amendments, as required.
Sincerely,
Marshall L. Lowen
Senior Environmental Consultant
TEKNIKA ENVIRONMENTAL CONSULTANTS
