CITY OF LOS ANGELES GUIDELINES FOR ASSESSMENT AND REMEDIATION OF MOLDThe information contained within this manual has been compiled from the following reference sources: The Environmental Protection Agency (EPA), The Centers for Disease Control (CDC), The California Department of Health Services (CA DHS), The NewYork Department of Health Services (NYDHS), American Conference of Governmental Industrial Hygienist (ACGIH) Guidelines for the Assessment of Bioaerosols in the Indoor Environment and the California Department of Occupational Safety and Health (CADOSH). Please note that this document presents recommendations on mold assessment and remediation. Currently there are no United States Federal, California State or Los Angeles City regulations for evaluating potential health effects of fungal contamination and remediation. These guidelines are subject to change as more information regarding fungal contaminants becomes available. April 2005.
PERSONNEL DEPARTMENT OCCUPATIONAL HEALTH AND SAFETY DIVISION
Molds are a group of organisms that belong to the kingdom Fungi. Fungi are neither animals nor plants and are classified in a kingdom of their own. Fungi include molds,yeasts, mushrooms and puffballs.
Molds live in the soil, on plants, and on dead or decaying matter. Molds are found in virtually every environment and can be detected, indoors and outdoors, year round. You are exposed to them daily in the air you breathe. Molds lack chlorophyll and must survive by digesting plant and other organic materials for food. Without molds, our environment would be overwhelmed with large amounts of dead plant matter.
Molds make tiny spores to reproduce, just as some plants produce seeds. These mold spores can be found in both indoor and outdoor air, and settled on indoor and outdoor surfaces. When mold spores land on a damp spot, they may begin growing and digesting whatever they are growing on in order to survive. Since molds gradually destroy the things they grow on, you can prevent damage to building materials and furnishings and save money by eliminating mold growth.
Moisture control is the key to mold control. Molds need both food and water to survive: since molds can digest most things, water is the factor that limits mold growth. Molds will often grow in damp or wet areas indoors. Common sites for indoor mold growth include bathroom tile, basement walls, areas around windows where moisture condenses,and near leaky water fountains or sinks. Common sources or causes of water or moisture problems include roof leaks, deferred maintenance, condensation associated with high humidity or cold spots in the building, localized plumbing failures or heavy rains, slow leaks in plumbing fixtures, and malfunction or poor design of humidification systems.
Molds can cause a variety of health problems such as allergic reactions, fungal infections, skin irritation, and aggravation of asthma symptoms. The types and severity of symptoms depend, in part, on the types of mold present, the extent of an individual’s exposure, the ages of the individuals, and their existing sensitivities or allergies. Most workers will not be affected by molds. In almost all cases of allergic or other illnesses, the symptoms are temporary. A small percentage of people may experience longer recovery times. It must be pointed out that the symptoms described for exposure to mold can also be due to other causes such as bacterial or viral infections, or other allergies.Therefore, it is important to consult your doctor if you are concerned about your health.
The key to mold control is moisture control. Solve moisture problems before they become mold problems! With this concept in mind, the Occupational Health and Safety Division assigns responsibility to the Department that oversees the affect facilities. The following mold prevention tips should be practiced:
Table 1: Water Damage - Cleanup and Mold Prevention Guidelines for Response to Clean Water Damage within 24-48 Hours to Prevent Mold Growth* Water-Damaged Material† Actions Books and papers -For non-valuable items, discard books and papers. -Photocopy valuable/important items, disscard originals. -Freeze (in frost-free freezer or meat llocker) or freeze-dry. Carpet and backing - dry Within 24-48 hours§ -Remove water with water extraction vacuuum. -Reduce ambient humidity levels with dehhumidifier. -Accelerate drying process with fans. Ceiling tiles -Discard and replace. Cellulose insulation -Discard and replace. Concrete or cinder block Surfaces -Remove water with water extraction vacuuum. -Accelerate drying process with dehumidiifiers, fans, and/or heaters. heaters. Fiberglass insulation -Discard and replace. Hard surface, porous flooring§ (Linoleum, ceramic tile, vinyl) -Vacuum or damp wipe with water and mildd detergent and allow to dry; scrub if necessary. -Check to make sure under flooring is dry; dry under flooring if necessary. Non-porous, hard surfaces (Plastics, metals) -Vacuum or damp wipe with water and mildd detergent and allow to dry; scrub if necessary. Upholstered furniture -Remove water with water extraction vacuum. -Accelerate drying process with dehumidiifiers, fans, and/or heaters.
-May be difficult to completely dry within 48 hours. If the piece is valuable, you may wish to consult a restoration/water damage professional who specializes in furniture. Wallboard (Drywall and gypsum board) -May be dried in place if there is no obbvious swelling and the seams are intact. If not, remove, discard, and replace. -Ventilate the wall cavity, if possible.. Window drapes -Follow laundering or cleaning instructions recommended by the manufacture. Wood surfaces -Remove moisture immediately and use dehumidifiers, gentle heat, and fans for drying. (Use caution when applying heat to hardwood floors.) -Treated or finished wood surfaces may bbe cleaned with mild detergent and clean water and allowed to dry. -Wet paneling should be pried away from wall for drying. * If mold growth has occurred or materials have been wet for more than 48 hours, consult Table 2 guidelines. Even if materials are dried within 48 hours, mold growth may have occurred. Items may be tested by professionals if there is doubt. Note that mold growth will not always occur after 48 hours; this is only a guideline. These guidelines are for damage caused by clean water. If you know or suspect that the water source is contaminated with sewage, or chemical or biological pollutants, then Personal Protective Equipment and containment are required by OSHA. An experienced professional should be consulted if you and/or your remediators do not have expertise remediating in contaminated water situations. Do not use fans before determining that the water is clean or sanitary. † If a particular item(s) has high monetary or sentimental value, you may wish to consult a restoration/water damage specialist. § The sub floor under the carpet or other flooring material must also be cleaned and dried. See the appropriate section of this table for recommended actions depending on the composition of the sub floor.
Table 2: Guidelines for Remediating Building Materials with Mold Growth Caused by Clean Water* Material or Furnishing Affected Cleanup Methods† Personal Protective Equipment Containment SMALL - Total Surface Area Affected Less Than 10 square feet (ft2) Books and papers 3 Minimum N-95 respirator, gloves, and goggles None required Carpet and backing 1, 3 Concrete or cinder block 1, 3 Hard surface, porous flooring (linoleum, ceramic tile, vinyl) 1, 2, 3 Non-porous, hard surfaces (plastics, metals) 1, 2, 3
Upholstered furniture & drapes 1, 3 Wallboard (drywall and gypsum board) 3 Wood surfaces 1, 2, 3 MEDIUM - Total Surface Area Affected Between 10 and 100 (ft2) Books and papers 3 Limited or Full Use professional judgment, consider potential for remediator exposure and size of contaminated area Limited Use professional judgment, consider potential for remediator/occupant exposure and size of contaminated area Carpet and backing 1,3,4 Concrete or cinder block 1,3 Hard surface, porous flooring (linoleum, ceramic tile, vinyl) 1,2,3 Non-porous, hard surfaces (plastics, metals) 1,2,3 Upholstered furniture & drapes 1,3,4 Wallboard (drywall and gypsum board) 3,4 Wood surfaces 1,2,3 LARGE - Total Surface Area Affected Greater Than 100 (ft2) or Potential for Increased Occupant or Remediator Exposure During Remediation Estimated to be Significant Books and papers 3 Full Use professional judgment, consider potential for remediator/occupant exposure and size of contaminated area Full Use professional judgment, consider potential for remediator exposure and size of contaminated area Carpet and backing 1,3,4 Concrete or cinder block 1,3 Hard surface, porous flooring (linoleum, ceramic tile, vinyl) 1,2,3,4 Non-porous, hard surfaces (plastics, metals) 1,2,3 Upholstered furniture & drapes 1,2,4 Wallboard (drywall and gypsum board) 3,4 Wood surfaces 1,2,3,4 Table 2 continued
*Use professional judgment to determine prudent levels of Personal Protective Equipment and containment for each situation, particularly as the remediation site size increases and the potential for exposure and health effects rises. Assess the need for increased Personal Protective Equipment, if, during the remediation, more extensive contamination is encountered than was expected. Consult Table 1 if materials have been wet for less than 48 hours, and mold growth is not apparent. These guidelines are for damage caused by clean water. If you know or suspect that the water source is contaminated with sewage, or chemical or biological pollutants, then the Occupational Safety and Health Administration (OSHA) requires PPE and containment. An experienced professional should be consulted if you and/or your remediators do not have expertise in remediating contaminated water situations.
†Select method most appropriate to situation. Since molds gradually destroy the things they grow on, if mold growth is not addressed promptly, some items may be damaged such that cleaning will not restore their original appearance. If mold growth is heavy and items are valuable or important, you may wish to consult a restoration/water damage/remediation expert. Please note that these are guidelines; other cleaning methods may be preferred by some professionals. Cleanup Methods
Method 1: Wet vacuum (in the case of porous materials, some mold spores/fragments will remain in the material but will not grow if the material is completely dried). Steam cleaning may be an alternative for carpets and some upholstered furniture.
Method 2: Damp-wipe surfaces with plain water or with water and detergent solution (except wood - use wood floor cleaner); scrub as needed.
Method 3: High-efficiency particulate air (HEPA) vacuum after the material has been thoroughly dried. Dispose of the contents of the HEPA vacuum in well-sealed plastic bags.
Method 4: Discard _ remove water-damaged materials and seal in plastic bags while inside of containment, if present. Dispose of as normal waste. HEPA vacuum area after it is dried.
Personal Protective Equipment (PPE)
Minimum: Gloves, N-95 respirator, goggles/eye protection
Limited: Gloves, N-95 respirator or half-face respirator with HEPA filter, disposable overalls, goggles/eye protection
Full: Gloves, disposable full body clothing, head gear, foot coverings, full-face respirator with HEPA filter
Limited: Use polyethylene sheeting ceiling to floor around affected area with a slit entry and covering flap; maintain area under negative pressure with HEPA filtered fan unit. Block supply and return air vents within containment area.
Full: Use two layers of fire-retardant polyethylene sheeting with one airlock chamber. Maintain area under negative pressure with HEPA filtered fan exhausted outside of building. Block supply and return air vents within containment area.
Table developed from literature and remediation documents including Bioaerosols: Assessment and Control (American Conference of Governmental Industrial Hygienists, 1999) and IICRC S500, Standard and Reference Guide for Professional Water Damage Restoration, (Institute of Inspection, Cleaning and Restoration, 1999); see Resources List for more information
If the water intrusion source/cause is not identified and repaired/eliminated then mold growth can occur. Control the water and you control the mold.
Inspection, Assessment and Sampling
The presence of mold, water damage, or musty odors should be addressed immediately. A visual inspection is the most important initial step in identifying a possible contamination problem. The extent of any water damage and mold growth should be visually assessed. This assessment is important in determining remedial strategies. Ventilation systems should also be visually checked when appropriate, particularly for damp filters but also for damp conditions elsewhere in the system and overall cleanliness. Ceiling tiles, gypsum wallboard (sheetrock), cardboard, paper, and other cellulosic surfaces should be given careful attention during the visual inspection. The use of equipment such as a boroscope, to view spaces in ductwork or behind walls, a moisture meter, to detect moisture in building materials, or a digital camera may be helpful in identifying and recording sources of fungal growth and the extent of water damage.
Bulk or surface sampling is not required to undertake a remediation. Remediation (as described in the Remediation section) of visually identified fungal contamination should proceed without further evaluation. Air sampling for molds should not be a part of a routine assessment as well. This is because decisions about appropriate remediation strategies can usually be made on the basis of a visual inspection. Regardless what type of mold is present you should arrange for its removal. Regulations for determining what a permissible limit of mold in the air is have not been established. Air sampling methods for some fungi are prone to false negative results and therefore cannot be used to definitively rule out contamination. Under certain circumstances sampling may need to be collected. The City Of Los Angeles Personnel Departments Occupational Health and Safety Division may take samples for the following reasons:
In all situations, the underlying cause of water accumulation must be rectified or fungal growth will occur. Any initial water infiltration should be stopped and cleaned immediately. An immediate response (within 48 hours) and thorough clean up, drying,and/or removal of water damaged materials will prevent or limit mold growth. If the source of water is elevated humidity, relative humidity should be maintained at levels below 60% to inhibit mold growth. Emphasis should be on ensuring proper repairs of the building infrastructure, so that water damage and moisture buildup does not recur. Three levels of abatement are described below. The size of the area impacted by fungal growth primarily determines the type of remediation. The sizing levels listed are based on professional judgment and practicality; currently there is not adequate data to relate the extent of contamination to frequency or severity of health effects. The goal of remediation is to remove or clean contaminated materials in a way that prevents the emission of fungi and dust contaminated with fungi from leaving a work area and entering an occupied or non-abatement area, while protecting the health of workers performing the abatement. The listed remediation methods were designed to achieve this goal, however, due to the general nature of these methods it is the responsibility of the people conducting remediation to ensure the methods enacted are adequate. The listed remediation methods are not meant to exclude other similarly effective methods. Any changes to the remediation methods listed in these guidelines, however, should be carefully considered prior to implementation.
Non-porous (e.g., metals, glass, and hard plastics) and semi-porous (e.g., wood, and concrete) materials that are structurally sound and are visibly moldy can be cleaned and reused. Cleaning should be done using a detergent solution. Porous materials such as ceiling tiles and insulation, and wallboards with mare than a small area of contamination should be removed and discarded. Porous materials (e.g., wallboard, and fabrics) that can be cleaned, can be reused, but should be discarded if possible. All materials to be reused should be dry and visibly free from mold. Routine inspections should be conducted toconfirm the effectiveness of remediation work.
The use of gaseous, vapor-phase, or aerosolized biocides for remedial purposes is not recommended. The use of biocides in this manner can pose health concerns for people performing the remediation as well as for people returning to the treated space if used improperly. Furthermore, the effectiveness of these treatments is unproven and does not address the possible health concerns from the presence of the remaining non-viable mold. The purpose of mold remediation is to remove the mold to prevent human exposure and damage to building materials and furnishings. It is necessary to remove the mold contamination, not just to kill the mold. Dead mold is still allergenic, and some dead molds are potentially toxic. In most cases, it is not possible or desirable to sterilize an area; a background level of mold spores will remain in the air. These spores will not grow if the moisture problem in the building has been resolved.
Remediation efforts should be conducted during non-business hours whenever feasible.
Level I: Small Isolated Areas (10 contiguous sq. ft. or less)
Level III: Extensive Contamination (greater than 100 contiguous sq. ft.)
A health and safety professional with experience performing microbial investigations should be consulted prior to remediation activities to provide oversight for the project. The following procedures at a minimum are recommended:
How Do You Know When You Have Finished Remediation/Cleanup?
There is no easy answer. Ultimately this is a judgment call. The following conditions must first be met prior to clearing an area for re- occupancy:
Communication with building occupants is essential for successful mold remediation. Some occupants will naturally be concerned about mold growth in their building and the potential health impacts. Occupant’s perceptions of the health risk may rise if they perceive that information is being withheld from them. The status of the building investigation and remediation should be openly communicated including information on any known or suspected health risks.
Small remediation efforts will usually not require a formal communication process, but do be sure to take individual concerns seriously and use common sense when deciding whether formal communications are required. When fungal growth requiring large-scale remediation is found, the remediation manager should notify occupants on the affected area(s) of its presence. Notification should include a description of the remedial measures to be taken and a timetable for completion. Group meetings held before and after remediation with full disclosure of plans and results can be an effective communication mechanism. Try and resolve issues and occupant concerns as they arise.
The four steps listed below should be followed while communicating during remediation:
In summary, the prompt remediation of contaminated material and infrastructure repair must be the primary response to mold contamination in city facilities. The simplest and most expedient remediation that properly and safely removes fungal growth from buildings should be used. In all situations, the underlying cause of water accumulation must be rectified or the fungal growth will recur. Emphasis should be placed on preventing contamination through proper building maintenance and prompt repair of water damaged areas.
Widespread contamination poses much larger problems that must be addressed on a case-by-case basis in consultation with the Occupational Health and Safety Division representative or the departmental safety specialist. Effective communication with building occupants is an essential component of all remedial efforts.
APPENDIX A AIR SAMPLING GUIDELINES FOR FINAL AIR MONITORING AND BACKGROUND AIR SAMPLING ON ALL PROJECTS GREATER THAN 100 SQUARE FEET
Prior to starting any remediation project over 100 square feet background air samples should be taken for documentation and comparison purposes. Background samples should use the following guidelines.
How to recognize, identify, & find toxic or allergenic indoor mold How to test for mold, clean up mold, or remove mold from buildings How to find, identify, and remove other indoor contaminants Indoor air quality cleanup, improvement, or corrective measures
Our Certified inspectors will answers most questions on what to do about mold, providing expert, un-biased information for owners, occupants, inspectors. How to recognize mold, how to test mold, how to clean up or remove mold, how to prevent mold in buildings, and what mold related illnesses and symptoms have been reported are all discussed in depth.
Our Company offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false- advertising, or junk science. Our contact info is at inspect-ny. com/appointment.htm. This website provides information and procedures for finding, testing, cleaning and preventing indoor mold, toxic black mold, green mold, testing building indoor air quality, and other sick house / sick building investigations.
MOLD RELATED ILLNESS - Asthma, Allergies, Lung, Neurological, Other Complaints? The following articles provide detailed information about mold-related illnesses.
Clinical Atlas of Mold Toxicity - An Online Description of Toxic, Pathogenic, Allergenic Fungi, Fungal Diseases Fiberglass Insulation Contains Mold© 2005 comments about a field study in process, & more about health hazards from fiberglass insulation - DJF Odors, Odor Detection, Smells, & Gases how to find and identify sources of noxious or toxic odors and gases Other environmental risks, Our much longer list: Asbestos, carbon monoxide, electromagnetic fields, etc. Pollen Allergens: identification, Products to Reduce Mold & Allergy Problems to reduce indoor mold or allergen levels: air cleaners, air purifiers, dust mite covers, vacuum cleaners, crawl space vents Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice Rodent control issues, including dander, fecal, and urine contamination of Buildings and Building insulation are discussed at our Mold Action Plan page. Sewage and Septic backup contamination in Buildings: inspection, testing, remediation, & references to expert sources PREVENT MOLD - How to Prevent Mold Growth and Avoid Mold Problems in Buildings The following articles provide detailed information about how to prevent mold growth in buildings and in their mechanical systems.
Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination Mold Action Guide after Flooding: How to Minimize Mold Damage After a Building Flood How to Prevent Mold: how to avoid mold growth in buildings: priorities, repairs, products Humidity Control to Avoid Mold: How Low Should You Keep Indoor Humidity to Avoid a Mold Problem Mold-Resistant Building Practices some detailed suggestions from an expert on preventing mold growth indoors Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous. Meruliporia incrassata - "Poria" the house eating fungus Meruliporia incrassata or perhaps a different mold, Serpula lacrymans - which one is the "house eating fungus" - what it house rotting mold like in a building and under the microscope MOLD DETECTION - Mold Identification Photos and Tips These articles explain how to find and recognize mold in a building. The articles include mold recognition photos, methods of visual inspection for mold, and explanation of how to cut your mold investigation cost and trouble by learning to recognize stuff that is not mold at all. We also explain that not all black mold is harmful. Some is cosmetic only. Visual inspection can answer some of these questions without mold testing.
How to Find and Test for Mold in Buildings - Looking for Mold - A "how to" photo and text primer on finding and testing for mold in Buildings Choosing a Sampling Point to conduct a mold test SAMPLING DRYWALL for mold Sampling Mistakes when conducting a mold test Attic Mold how to recognize mold in an attic, when is it a problem? Basement mold how to recognize mold in a basement, is it a problem? Basketball Mold Syndrome - BBMS- sudden attention to old clues in buildings makes them seem brand new to some observers Crawlspace mold how to recognize mold in a crawl space, where will it be, is it a problem? Do-It-Yourself-Warnings for people inspecting and testing for toxic mold Mold on Dirt Floors in basements and crawl spaces MOLD ON or IN CARPETS where to look for mold on and under carpeting Hidden Mold a list and photos of other places to look for hidden or hard to spot mold contamination in buildings Hidden Mold: photo guide shows how to find hidden toxic or even simply cosmetic mold in buildings
What Does Mold Look Like? Mold spores in the Home - a Photo ID Library for detection and identification of mold allergens Stuff That is Not Mold but is often mistaken for it - things you may not want to test. Not all "black mold" is toxic or harmful. TRAPPED MOLD BETWEEN WOOD SURFACES - do we need to look for, find, remove, or try to kill mold on mating wood surfaces such as between floor joist tops and subfloor underside, or between a wall sill plate and the subfloor surface? What about between layers of wood flooring and subflooring? Lighting: Proper use of lighting discloses hard to see but toxic light or white mold colonies on building surfaces - read this if you're doing your own tape sampling for mold. Lighting, using to find mold - proper use of a flashlight can help spot mold on paneling and other building surfaces Mold Investigation Tips for Home Inspectors how to find mold, where to look, what is likely to be important. Advice to Building inspectors intending to inspect or test for toxic or problematic mold indoors, mold inspection methods, and mold test methods which are valid or invalid Most Common Indoor Molds Found in Buildings, A Table of Meruliporia incrassata the house eating fungus or "poria" may be mistaken for wood rot.
MOLD TEST PROCEDURES - Valid and in-valid mold testing methods & protocols. Are some mold test kits junk science? Please see Mold Sampling Methods in the Indoor Environment and in addition, the mold test critique articles listed just below. Validity of Common Indoor Mold Sampling Techniques Examining the Validity of Current Indoor Mold Sampling Techniques, Daniel Friedman, (Illustrated Power Point Presentation) 15th Annual North Carolina/South Carolina Environmental Association Technical Conference Tape: Mold Testing by Tape of a Moldy Surface "bulk" or "tape" samples and their interpretation - a brief tutorial Tape: How to Report Mold Levels in Tape Samples of Surfaces in Buildings Air: Mold Testing by Air Samples & their interpretation - a brief tutorial on indoor air sampling for mold - are spore counts per cubic meter of air accurate and valid? Using air sampling to determine if a mold problem is "present" or "absent" and the role of cultures for "viable spore sampling" are criticized. Air sampling used alone is an unreliable way to look for mold and is highly questionable as a means of characterizing a precise mold exposure level indoors. Basketball Mold Syndrome - BBMS- sudden attention to old clues in buildings makes them seem brand new to some observers Carpet Mold Inspection how to look for mold in carpets Carpet Mold Test Guide suggestions for alternative methods to test carpeting for mold Culture: Mold Testing by Cultures & "Home Test Kits for Mold" - Validity of Settlement Plates or Swabs to test for toxic mold in Buildings - a brief tutorial Mold Sampling Methods in the Indoor Environment a critique of popular mold testing methods - Is your "expert" using valid methods? Is your mold test kit worth the bother? (Technical Paper.) Toxic Mold Testing Methods Compared, also Toxic Gas Testing Methods and MVOC's - valid vs. invalid methods, recommendations compares air sampling for mold, surface or tape sampling for mold, culture or swab sampling for mold, and gas MVOC sampling methods for mold or other toxins, and organizes links to papers on each of these topics. A Comparison of Some Indoor Air Sampling Devices - simultaneous application of popular sampling cassettes and slide samplers allows comparison of typical particle collection variation by device in actual field use. A field study in process by DJF, 2008 - 2005 (Technical Paper) Burkard personal air sampler used by many residential investigators (we use multiple units simultaneously in some investigations). We also employ other residential building sampling equipment for surface, air, vacuum, and bulk sample collection methods as well as for gases. Alternative, low-cost air sampling equipment and methods such as the mini-vacuum pump and Zefon Air-o-Cell or Allergenco-d cassettes or MCE filter cassettes for viable, non-viable or other forensic particle identification in Buildings. A field study in process by DJF, 2005 - 2006 (Technical Paper) Allergenco Mk-III time-lapse impaction air sampling equipment - study changes in particle dispersion under varying conditions (furnace on/off) A field study in process by DJF, 2004 - 2006 (Technical Paper) Mold Testing: Bulk or Tape Surface Samples and their interpretation - a quick tutorial A brief introduction to using adhesive tape to collect particle samples such as from mold-covered surfaces; scrapes onto microscope slide and Vacuum Samples of Building Cavities: Wall Check type vacuum pump and canister permits "sampling" of mold and allergens in wall, ceiling, and floor cavities but our direct field testing indicates that this method is highly unreliable.
When the building interior surfaces were demolished we then performed a visual inspection and collected bulk surface samples using tape. The wall check samples were completely unable to detect large and significant mold contamination in the cavities of this building.
We postulate that even with mechanical agitation (banging on the wall during wall check sampling) the flow rate of the sampling method does not move enough air to reliably pick up surface contamination unless the mold genera/species happens to be at a particularly high state of active sporulation. The tool remains in the professional's arsenal, to be used with discretion. Vacuum samples of Soft Goods of carpeting, drapes, furniture, clothing permits testing for mold contamination. We use this method for screening of areas where mold is not visible, and in clearance testing. MOLD CULTURES - Validity and Usefulness of Mold Cultures & Culture-Based Home Test Kits for mold For a quick to understand overview of the validity and usefulness or perhaps not-usefulness of culture tests for mold, see Validity of Cultures (settlement plates or swabs) to find toxic mold in Buildings which is an overview and critique of using mold cultures, settlement plates, petri dishes, and cultured swab samples, and air sample testing limitations for determining what's in a Building, and which tests are useful in different situations.
For more thorough detail see Shortcomings of cultured mold samples which lists a number of detailed concerns about viable spore traps and culture media for Building problem detection
MOLD CLASSES, LEVELS - Mold Hazard levels, Mold Spore Count Validity, Interpreting Mold Counts, and Classes of Mold Please see MOLD CLASSES, LEVELS for the full text article on this topic.
Airborne Mold Spore Counts: Airborne Mold Spore Counts - are indoor fungal spore counts valid? Mold Exposure Standards: Exposure Standards for Mold, Levels of Severity of Indoor Mold Contamination - Various Published Standards of Permissible Mold Exposure Limits: at what level is toxic or allergenic mold a problem? - What does your "spores per cubic meter of air" or "spore count" really mean - if anything? MOLD EXPOSURE RISK LEVELS: How to Determine Mold Contamination Probability or Mold Exposure Risk Levels in Buildings Based on Visual Inspection MOLD LEVEL IN AIR, VALIDITY: Mold Spore Counts - are indoor fungal spore counts valid? Mold Hazard Levels: Mold Classes, Levels of what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully? Mold Reporting: How to Report Mold Levels in Mold Test Samples of Surfaces in Buildings Mold Spore Count Per Cubic Meter: airborne density counts of mold spores per cubic meter of air - how to interpret low mold spore trap count results MOLD REPORTS - Mold and IAQ Investigation Reports Indoor Air / Toxic Mold Field Investigation & Lab Reports - what to look for in a toxic mold field investigation report and mold test laboratory report © Indoor Air / Toxic Mold Test Lab Reports - what to look for in a toxic mold test laboratory report © How to Report Mold Levels in Mold Test Samples of Surfaces in Buildings - suggested non-quantitative definitions Sick House Investigation Questionnaire used to collect occupant and Building information that may aid the investigator ©
Rusts, or Uredinales, include Puccinia rusts that invade corn, cotton, mint, sugar cane, and wheat, also Melampsora - flax, Hemileia - coffee, Cronartium - pine, Uromyces - chickpea, bean, and many others. There are about 5000 species in this group.
Our lab photo (left) shows typical Urediniospores from an air sample where rust spores were frequent. (These are not wheat rust spores).
Wheat leaf rust causes small (1/32") reddish-brown pustules or blisters to appear on the surface of plant leaves.
The wheat leaf rust Puccinia recondita spores may also produce a reddish brown dust (mold spore powder).
Mature wheat leaf rust fungus pustules and their fungal spores may be dark brown or even black. Wheat leaf rust spores live only on live leaves but survive the winter on leaf fragments, periodically reaching epidemic proportions in the wheat crop. Interestingly, the location of wheat rust on the plant can indicate its source: rust on upper plant leaves suggests that spores blew into the wheat field from a more distant location, while wheat rust pustules found on lower plant leaves indicate that the rust fungus over-wintered on leaves in the local field.
In addition to application of systemic wheat foliar fungicides such as Tilt, Quadris, and Mancozeb, some varieties of wheat are bred to resist this fungus, and experts note that resistant species are the best way to control wheat rust epidemics. More information about wheat leaf rust is at the Kansas State University Website.
Rust spores can be quite beautiful, belying the crop damage they may cause, as our lab photo of Pileolaria brevipes (a rust spore found in an air sample we collected in San Diego, CA) shows at left.
While InspectAPedia.com focuses attention on building and indoor environmental concerns, the history and forensic work on Puccinia recondita is so important to the world's wheat crop and serves so well as an example of good investigative work that we have included this expanding topical section.
Contact Us to contribute to this section or for other website critique or content suggestions.
TECHNICAL PROCEDURES - Technical & Laboratory Procedures Good Laboratory and Microscope Procedures are critical in making sense of field samples. Competent, trained, experienced aerobiologists, mycologists, and microbiologists can identify sample contents with good accuracy. Depending on the experience of the laboratory, it is also possible to interpret the meaning of the sample for the Building and its occupants. Laboratory professionals who have also performed the field inspection can make useful extrapolations from lab results. Hasty work by disinterested parties may be less useful for Building occupants and owners.
Please see TECHNICAL & LAB PROCEDURES for the full text article on this topic.
Air Sampler Specifications Required for Airborne Particle Calculations