How to Identify the Cause of a Mold and Mildew Problem

As per the USEPA website -
Mold and mildew are commonly found on the exterior wall surfaces of corner rooms in heating climate locations. An exposed corner room is likely to be significantly colder than adjoining rooms, so that it has a higher relative humidity (RH) than other rooms at the same water vapor pressure. If mold and mildew growth are found in a corner room, then relative humidity next to the room surfaces is above 70%. However, is the RH above 70% at the surfaces because the room is too cold or because there is too much moisture present (high water vapor pressure)?
The amount of moisture in the room can be estimated by measuring both temperature and RH at the same location and at the same time. Suppose there are two cases. In the first case, assume that the RH is 30% and the temperature is 70^oF in the middle of the room. The low RH at that temperature indicates that the water vapor pressure (or absolute humidity) is low. The high surface RH is probably due to room surfaces that are "too cold." Temperature is the dominating factor, and control strategies should involve increasing the temperature at cold room surfaces.
In the second case, assume that the RH is 50% and the temperature is 70^oF in the middle of the room. The higher RH at that temperature indicates that the water vapor pressure is high and there is a relatively large amount of moisture in the air. The high surface RH is probably due to air that is "too moist." Humidity is the dominating factor, and control strategies should involve decreasing the moisture content of the indoor air.

Guidelines on Assessment and Remediation of Fungi in Indoor Environments

Guidelines on Assessment and Remediation of Fungi in Indoor Environments

As per NYC Dept of Health and Mental Hygiene - This 2008 document revises existing guidelines and supersedes all prior editions. It is based both on a review of the current literature regarding fungi (mold) and on comments from a review panel consisting of experts in the fields of mycology/microbiology, environmental health sciences, environmental/occupational medicine, industrial hygiene, and environmental remediation.

To see the entire guidelines go to http://www.nyc.gov/html/doh/html/epi/moldrpt1.shtml

How To Get Rid of Mold and Prevent Mold Growth

Old House Journal recently posted a good article on mold in the home. It discusses what mold is, how it grows and spreads, factors that contribute to mold growth and ideas on how to inhibit or removal mold. Ventilation and dehumidification are very important in preventing mold growth in your home. To read the compete article go to:

http://www.oldhousejournal.com/how_to_get_rid_of_mold/magazine/1591

Real Estate Issue: Mold and Mildew in Home

A good article on mold in homes that are up for sale and what the buyer should know can be found at:
http://www.examiner.com/x-3942-Baltimore-Real-Estate-Investing-Examiner~y2009m3d13-Experts-Cash-in-on-Toxic-Mold

Questions That May Assist in Determining Whether a Mold Problem Currently Exists

Do you think you have mold, mildew or a moisture issue? As per OSHA, some Questions That May Assist in Determining Whether a Mold Problem Currently Exists are:

• Are building materials or furnishings visibly moisture damaged?
• Have building materials been wet more than 48 hours?
• Are there existing moisture problems in the building?
• Are building occupants reporting musty or moldy odors?
• Are building occupants reporting health problems that they think are related to mold in the indoor environment?
• Has the building been recently remodeled or has the building use changed?
• Has routine maintenance been delayed or the maintenance plan been altered?

Always consider consulting a health professional to address any employee health concerns.

Source: http://www.osha.gov/dts/shib/shib101003.html

Got Mold? Frequently Asked Questions About Mold

The Washington State Department of Health - Office of Environmental Health and Safety provides a webpage that answers many frequently asked questions about mold. Some of these are:

What are molds?

Molds are tiny microscopic organisms that digest organic matter and reproduce by releasing spores. Molds are a type of fungi and there are over 100,000 species. In nature, mold helps decompose or break-down leaves, wood and other plant debris. Molds become a problem when they go where they are not wanted and digest materials such as our homes.

What makes molds grow in my home?

Mold enters your home as tiny spores. The spores need moisture to begin growing, digesting and destroying. Molds can grow on almost any surface, including; wood, ceiling tiles, wallpaper, paints, carpet, sheet rock, and insulation. The mold grows best when there is lots of moisture from a leaky roof, high humidity, or flood. There is no way to get rid of all molds and mold spores from your home. But you can control mold growth by keeping your home dry.

Can I be exposed to mold?

When molds are disturbed, they release spores into the air. You can be exposed by breathing air containing these mold spores. You can also be exposed through touching moldy items, eating moldy food or accidental hand to mouth contact.

Do molds affect my health?

Most molds do not harm healthy people. But people who have allergies or asthma may be more sensitive to molds. Sensitive people may experience skin rash, running nose, eye irritation, cough, nasal congestion, aggravation of asthma or difficulty breathing. People with an immune suppression or underlying lung disease, may be at increased risk for infections from molds. A small number of molds produce toxins called mycotoxins. When people are exposed to high levels of mold mycotoxins they may suffer toxic effects, including fatigue, nausea, headaches, and irritation to the lungs and eyes. If you or your family members have health problems that you suspect are caused by exposure to mold, you should consult with your physician.

When is mold a problem?

You know you have mold when you smell the "musty" odor or see small black or white specks along your damp bathroom or basement walls. Some mold is hidden growing behind wall coverings or ceiling tiles. Even dry, dead mold can cause health problems, so always take precautions when you suspect mold.Mold is often found in areas where water has damaged building materials and furniture from flooding or plumbing leaks. Mold can also be found growing along walls where warm moist air condenses on cooler wall surfaces, such as inside cold exterior walls, behind dressers, headboards, and in closets where articles are stored against walls. Mold often grows in rooms with both high water usage and humidity, such as kitchens, bathrooms, laundry rooms, and basements. If you notice mold or know of water damaged areas in your home, it is time to take action to control its growth

For more answers to common questions about mold go to the Source: http://www.doh.wa.gov/ehp/ts/IAQ/GOT_Mold.html

Home Moisture Audit Overview

As per Environmental Health Watch - Moisture is both a blessing and a curse. When you have just what you need your health and the health of your buildings is ensured. But when you have too much, your buildings can fail in many ways that can not only damage the structure but affect your health and well-being. The information that follows is a tool to help you keep moisture in your house at acceptable and healthy levels.

The site has good information on moisture issues and problems and provides handy audit sheets. Go to the source for these sheets and more info http://www.ehw.org/Healthy_House/HH_Moist_Audit.htm

HVAC Cleaning and Remediation for Mold and Mildew

As per the NIOSH Interim Recommendations for the Cleaning and Remediation of Flood-Contaminated HVAC Systems: A Guide for Building Owners and Managers http://www.cdc.gov/niosh/topics/flood/Cleaning-Flood-HVAC.html, the following are recommendations:

HVAC Cleaning and Remediation

• Remove all flood-contaminated insulation surrounding and within HVAC systemcomponents. Discard these contaminated materials appropriately followingapplicable Federal, State, and local regulations.
• Remove contaminated HVAC filter media and discard appropriately followingapplicable Federal, State, and local regulations.
• After removing any insulation and filters, clean all flood-contaminated HVACsystem component surfaces with a HEPA-filtered vacuum cleaner to remove dirt,debris, and microorganisms. Pay special attention to filter racks, drain pans,bends and horizontal sections of air ducts where debris can collect.
• After removing any insulation or debris, disinfect all HVAC system componentsurfaces while the HVAC system is not operating. Use a solution of 1 cup ofhousehold chlorine bleach in a gallon of water. Do not mix bleach with othercleaning products that contain ammonia.
• Follow the disinfection procedure with a clean water rinse. Depending on theamount of debris present, it may be necessary to mechanically clean the HVACsystem component surfaces with a steam or a high-pressure washer beforeusing the disinfectant.
• Note: Remove and discard HVAC system components that arecontaminated with flood water and cannot be effectively cleaned and disinfected. Replace them with new components.
• After cleaning and disinfecting or replacing the HVAC system components,replace the insulation – preferably with an external (i.e. not in the air stream)smooth-surfaced insulation to help prevent debris and microorganisms fromcollecting in the future.
• Make sure that the HVAC system fan has been removed and serviced (cleaned,disinfected, dried thoroughly, and tested) by a qualified professional before it isplaced back into the air-handling unit.
• During the cleaning and remediation process, consider upgrading the HVACsystem filtration to the highest efficiency filters practical given the static pressureconstraints of the HVAC system fan. This step has been shown to be one of the most cost-effective ways to improve the long-term quality of the indoorenvironment, since it reduces the amount of airborne dusts and microorganisms.

Source: www.cdc.gov

Mold Prevention Tips From the CDC

MOLD PREVENTION TIPS

As per the CDC website http://www.cdc.gov/mold/dampness_facts.htm, these are tips to preventing mold:

Keep the humidity level in your home between 40% and 60%. Use an air conditioner or a dehumidifier during humid months and in damp spaces, like basements.

Be sure your home has enough ventilation. Use exhaust fans which vent outside your home in the kitchen and bathroom. Make sure your clothes dryer vents outside your home.

Fix any leaks in your home’s roof, walls, or plumbing so mold does not have moisture to grow.

Clean up and dry out your home thoroughly and quickly (within 24–48 hours) after flooding.

Add mold inhibitors to paints before painting.

Clean bathrooms with mold-killing products.

Remove or replace carpets and upholstery that have been soaked and cannot be dried promptly.

Consider not using carpet in rooms or areas like bathrooms or basements that may have a lot of moisture.

To learn more about preventing mold in your home, see the Environmental Protection Agency's publication A Brief Guide to Mold, Moisture, and Your Home at http://www.epa.gov/iaq/molds/moldguide.html

Indoor Air Quality - Biological Contaminants

As per the US EPA website - Biological contaminants include bacteria, molds, mildew, viruses, animal dander and cat saliva, house dust, mites, cockroaches, and pollen (see more about Asthma triggers at www.epa.gov/asthma). There are many sources of these pollutants. Pollens originate from plants; viruses are transmitted by people and animals; bacteria are carried by people, animals, and soil and plant debris; and household pets are sources of saliva and animal dander. The protein in urine from rats and mice is a potent allergen. When it dries, it can become airborne. Contaminated central air handling systems can become breeding grounds for mold, mildew, and other sources of biological contaminants and can then distribute these contaminants through the home.

By controlling the relative humidity level in a home, the growth of some sources of biologicals can be minimized. A relative humidity of 30-50 percent is generally recommended for homes. Standing water, water-damaged materials, or wet surfaces also serve as a breeding ground for molds, mildews, bacteria, and insects. House dust mites, the source of one of the most powerful biological allergens, grow in damp, warm environments.

For more information go to the source http://www.epa.gov/iaq/biologic.html

Indoor Air Health Issues

A good article was recently published entitled "Sniffing out danger at home - Breathing indoors can be bad for your health". This article can be found at http://www.paloaltoonline.com/news/show_story.php?id=10840 . The article is about potential hazards in your home including mildew, mold, chemicals, asbestos, lead and more that can be harmful if you breath or ingest these materials.

Website Links For Mold Resources and Information

Indoor Air - Mold This page provides information about mold resources.URL: http://www.epa.gov/iaq/molds/index.html

Mold Resources This page discusses how mold is produced and the associated risks to human health and property.URL: http://www.epa.gov/iaq/molds/moldresources.html

A Brief Guide to Mold, Moisture, and Your Home This guide provides information and guidance for homeowners and renters on how to clean up residential mold problems.URL: http://www.epa.gov/iaq/molds/moldguide.html

Sources of Indoor Air Pollution - Biological Pollutants Provides information about biological pollutants.URL: http://www.epa.gov/iaq/biologic.html

Indoor Environment Management Branch: Children's Health Initiative: Toxic Mold Outbreaks of the fungi Stachybotrys atra (S. atra) have been identified as being associated with the deaths of infants in Cleveland, Ohio.URL: http://www.epa.gov/appcdwww/iemb/child.htm

Mold Remediation in Schools and Commercial Buildings This document provides information about mold remediation in commercial buildings and schools.URL: http://www.epa.gov/iaq/molds/index.html

Asthma Triggers - Molds Molds can trigger asthma episodes in individuals with an allergic reaction to mold.URL: http://www.epa.gov/iaq/asthma/molds.html

IAQ Tools for Schools Kit - IAQ Coordinator's Guide: Appendix H: Mold and Moisture Provides information about mold and moisture.URL: http://www.epa.gov/iaq/schools/tfs/guideh.html

Healthy School Environments: Mold and Moisture Provides information about mold and moisture in schools.URL: http://cfpub.epa.gov/schools/top_sub.cfm?t_id=41&s_id=31

Building Air Quality: A Guide for Building Owners and Facility Managers: Appendix C: Moisture, Mold and Mildew Provides information about mold, mildew and moisture.URL: http://www.epa.gov/iaq/largebldgs/pdf_files/appenc.pdf

Should You Have the Air Ducts in Your Home Cleaned?

Should You Have the Air Ducts in Your Home Cleaned? - excerpt on duct cleaning and mold follows, please review the entire document for additional information on duct cleaning and mold.

You should consider having the air ducts in your home cleaned if:

There is substantial visible mold growth inside hard surface (e.g., sheet metal) ducts or on other components of your heating and cooling system. There are several important points to understand concerning mold detection in heating and cooling systems:

Many sections of your heating and cooling system may not be accessible for a visible inspection, so ask the service provider to show you any mold they say exists.


You should be aware that although a substance may look like mold, a positive determination of whether it is mold or not can be made only by an expert and may require laboratory analysis for final confirmation. For about $50, some microbiology laboratories can tell you whether a sample sent to them on a clear strip of sticky household tape is mold or simply a substance that resembles it.

If you have insulated air ducts and the insulation gets wet or moldy it cannot be effectively cleaned and should be removed and replaced.

If the conditions causing the mold growth in the first place are not corrected, mold growth will recur.

www.epa.gov/mold/moldresources.html