Description
The Collection and Interpretation of Indoor Mold Samples
Table of Contents
LIST OF ABBREVIATIONS VI
CHAPTER 1: INTRODUCTION 1
1.0 PURPOSE 2
1.1 COMPARISON OF METHODS 3
1.2 DATA QUALITY 4
1.3 VISUAL INSPECTION V. SAMPLING 5
1.4 THE SAMPLING STRATEGY 7
1.4.1 Stratification of Indoor Spaces by Condition 7
1.4.2 The Sampling Plan 9
1.5 OCCUPANT HEALTH EFFECTS 10
1.5.1 Sampler Saturation Effects 10
1.5.2 Hidden Mold 13
1.5.3 Gender Effects 14
CHAPTER 2: DATA INTERPRETATION METHODS 16
2.0 INTRODUCTION 17
2.1 COMPARISON OF METHODS 19
2.2 THE REFERENCE METHOD 21
2.3 THE CONTROL METHOD 22
2.4 THE DATABASE METHOD 25
2.5 DECISION CRITERIA 29
2.6 NUMERICAL GUIDELINES 33
CHAPTER 3: TOTAL AIRBORNE FUNGAL SPORES 37
3.0 INTRODUCTION 38
3.1 ROTAMETERS 39
3.2 SAMPLER CHARACTERISTICS 40
3.2.1 Aspiration Efficiency 41
3.2.2 Collection Efficiency 43
3.2.3 Retention of Chaetomium Spores 44
3.2.4 Retention Efficiency: Asp/Pen-like Spores 46
3.2.5 Project Objective 48
3.3 SAMPLING TIME 50
3.3.1 Short-term Samples 50
3.3.2 Long-term Samples 51
3.3.3 False Negatives 55
3.4 INTERPRETING TOTAL AIRBORNE FUNGAL SPORES 60
3.5 DATA LIMITATIONS 62
CHAPTER 4: CARPET DUST SAMPLES 63
4.0 INTRODUCTION 64
4.1 WEIGHT V. AREA BASIS RESULTS 66
4.2 COMPARISON OF CARPET SAMPLING METHODS 68
4.2.1 Sampling Parameters 68
4.2.2 Fungal Concentrations in Clean Carpets 70
4.2.3 Comparison of Sampling Methods 70
4.2.4 Assessing Carpet Condition 72
4.3 ENVIRONMENTAL RELATIVE MOLDINESS INDEX [ERMI] 74
4.3.1 Limitations of ERMI Comparisons 76
4.3.2 Fungal Loading 78
4.3.3 ERMI False Negatives 80
CHAPTER 5: WALL CAVITY SAMPLES 83
5.0 INTRODUCTION 84
5.1 PURPOSE 84
5.2 VISUAL INSPECTION 86
5.3 SAMPLING PARAMETERS 88
5.3.1 Sample Volume 88
5.3.2 Insulation in Walls 90
5.3.3 Quiescent versus Aggressive Sampling 90
5.4 COMPARISON OF SAMPLERS 93
5.4.1 Samplers and Sample Probes 93
5.4.2 Sampler Performance 94
5.5 INTERPRETATION OF WALL CAVITY DATA 98
5.5.1 Dominant Spore Types 98
5.5.2 Basis for Numerical Guidelines 98
5.5.3 Numerical Guidelines for Wall Cavity Samples 100
5.5.4 Culturable Fungi v. Total Spores 101
CHAPTER 6: SOFT-SURFACE SAMPLES 105
6.0 INTRODUCTION 105
6.1 ASSESSING IICRC CONDITION 105
6.1.1 Re-cleaning Office Furniture 106
6.1.2 Re-cleaning Residential Furniture 108
6.1.3 Assessing IICRC Condition 109
6.2 AIRBORNE V. SURFACE MOLD 110
CHAPTER 7: SAMPLE ANALYSIS BY QPCR 113
7.0 INTRODUCTION 113
7.1 MICROSCOPY V. QPCR 114
7.1.1 Agreement between Methods 114
7.1.2 Environmental Factors 115
7.1.3 Spores v. Spore-equivalents 116
7.2 EXAMPLES OF QPCR ANALYSIS 116
7.2.1 Carpet Samples 116
7.2.2 House Dust 117
7.2.3 Clothing Samples 117
7.2.4 Air Ducts 118
7.2.5 Personal Items 119
7.2.6 Hospital Critical-care Areas 120
CHAPTER 8: DATA DISTRIBUTIONS AND LOG PLOTS 123
8.0 INTRODUCTION 123
8.1 NORMAL AND LOGNORMAL DISTRIBUTIONS 123
8.2 CUMULATIVE PERCENTILE DISTRIBUTIONS 125
8.2.1 Selecting the Data 125
8.2.2 Constructing the Distribution: Simple Method 126
8.2.3 Constructing the Distribution: Filiben’s Method 128
8.2.4 Shape of the Log plot 130
8.2.5 Geometric Standard Deviation 132
REFERENCES 135
APPENDIX A: AN OPINION ON ASSESSING THE HEALTH EFFECTS OF MOLD 139
APPENDIX B: COMPARISON OF INDOOR AND OUTDOOR AIRBORNE FUNGAL SPORE CONCENTRATIONS IN
RESIDENTIAL PROPERTIES 145
APPENDIX C: A COMPARISON OF SAMPLING METHODS FOR STRATIFYING CARPETS FOR FUNGI 161
APPENDIX D: A COMPARISON OF SAMPLING METHODS FOR DETECTING FUNGI IN CARPETS 171
APPENDIX E: DETECTING AIRBORNE MOLD IN HOSPITAL AIR USING MICROSCOPY AND QPCR ANALYSIS 187
