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ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY
AIR CLEANER PURIFIER TYPES
AIR POLLUTANTS, COMMON INDOOR
AIR QUALITY IMPROVEMENT STRATEGIES
AIRBORNE PARTICLE ANALYSIS METHODS
ALLERGEN TESTS for BUILDINGS
ASBESTOS IDENTIFICATION IN BUILDINGS
BACKDRAFTING HEATING EQUIPMENT
BLACK MOLD, TOXIC & ALLERGENIC
BLEACHING MOLD, Advice about
BOOKSTORE - ENVIRONMENTAL
CADMIUM in the HOME
CARBON MONOXIDE - CO
CARPETING & INDOOR AIR QUALITY
CAT DANDER in BUILDINGS
CELL PHONE RADIATION
CHEMICAL CONTAMINANTS in WATER
COMBUSTION PRODUCTS & IAQ
DIRECTORY of MOLD / ENVIRONMENTAL EXPERTS
DUST SAMPLING PROCEDURE
EMERGENCY RESPONSE, IAQ, GAS, MOLD
EMF ELECTROMAGNETIC FIELDSRE
ENDOCRINE DISRUPTERS at BUILDINGS
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOR TILE ASBESTOS IDENTIFICATION
FUNGICIDAL SPRAY & SEALANT USE
GAS EXPOSURE EFFECTS, TOXIC
HEATING OIL EXPOSURE HAZARDS, LIMITS
HOUSE DUST ANALYSIS
HOUSE DUST COMPONENTS
HUMIDITY CONTROL & TARGETS INDOORS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
LAB PROCEDURES MICROSCOPE TECHNIQUES
LEAD POISONING HAZARDS GUIDE
LEGIONELLA LEGIONNAIRES' DISEASE
LIGHT, GUIDE to FORENSIC USE
METHANE GAS SOURCES
MILDEW in BUILDINGS ?
MOISTURE CONTROL in BUILDINGS
MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
MOLD CONSULTANTS / INSPECTORS
MOLD DETECTION & INSPECTION GUIDE
MOLD EXPERT, WHEN TO HIRE
MOLD RELATED ILLNESS GUIDE
MSDS MATERIAL SAFETY DATA SHEETS
MVOCs & MOLDY MUSTY ODORS
NOISE / SOUND DIAGNOSIS & CURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
OIL, HEATING, EXPOSURE HAZARDS, LIMITS
OIL HEAT ODORS & NOISES
OIL SPILL CLEANUP / PREVENTION
PET ALLERGENS / PET DANDER
PET STAINS & MARKS in BUILDINGS
PLASTIC ODORS-SCREENS, SIDING
PLUMBING SYSTEM ODORS
PVC - VINYL BUILDING PRODUCTS
RADON HAZARD TESTS & MITIGATION
SAFETY HAZARDS GUIDE
SAFETY HAZARDS & INSPECTIONS
METHANE GAS HAZARDS
SEPTIC SYSTEM ODORS
SEWAGE BACKUP TEST & CLEANUP
SEWER GAS ODORS
SMELL PATCH TEST to Track Down Odors
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
SULPHUR & SEWER GAS SMELL SOURCES
UFFI UREA FORMALDEHYDE FOAM INSULATION
URETHANE FOAM Deterioration, Outgassing
VINYL CHLORIDE HEALTH INFO
VOCs VOLATILE ORGANIC COMPOUNDS
WATER ODORS, CAUSE CURE
This article explains the impact of radon gas contamination levels in air or water on real estate sales and property values.
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As reported in Best Practices Guide to Residential Construction:
The EPA and the U.S. Geological Survey have rated every county in the United States as Zone 1 to 3 for radon risk. Links to state maps with county by- county risk levels can be found at www.epa.gov/ radon/zonemap.html.
The EPA recommends that all homes in Zone 1 counties be built with radon-resistant features, which can be easily upgraded to a radon remediation system if needed.
Since homes in Zones 2 and 3 can also have high levels, it is best to check with your state radon office to see if they are aware of any local “hot spots.”
The techniques for radon-resistant building vary for different foundation types and site conditions, but all contain the six basic elements described below.
Following these steps creates a passive soil depressurization system, which sufficiently lowers radon levels in about 50% of homes requiring mitigation.
If radon levels need to be lowered further, the system can be easily converted to an active system by adding an inline fan, which can meet the target levels in nearly all cases (see Figure at above left, showing a typical radon mitigation system installation).
The goal of radon remediation is to lower the average indoor radon gas level to less than 4 pCi/L, and preferably 2 pCi/L.
A post mitigation radon test of 2 to 7 days should be done within 30 days of system installation. For an accurate reading, all windows and doors must be closed 12 hours before and during the test, except for normal use for entry and exit.
-- Adapted with permission from Best Practices Guide to Residential Construction.
Watch out: home ventilation systems, particularly powerful exhaust fans, can subvert a typical sub-slab suction type radion mitigation system by creating negative air pressures within the building. The radon system needs to be able to handle these pressure variations in the home.
See VENTILATION, BALANCED for an optimum approach to bringing in fresh outdoor air without increasing heating or cooling costs and without risking subverting the radon mitigation system.
Also see BACKDRAFTING HEATING EQUIPMENT for warnings about potentially fatal carbon monoxide hazards if exhaust fans cause back-drafting of heating appliance exhaust into the building.
For a Thorough Background in Radon Hazards, Radon Mitigation, & the History of Radon Concerns in the U.S. also see these articles reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
Also see "Radon Basics", Q&A article, Solar Age, April 1984, includes advice for radon-resistant construction for an underground house built of concrete
Continue reading at RADON IN WATER or select a topic from the More Reading links shown below.
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