Hazard 1: Damp & mold growth

Housing Health and Safety Rating

System

2012 1

Description of the Hazard

• Dampness and/or high humidity are

associated with an increased prevalence of

house dust mites and mold or fungal growths,

which can be damaging to both physical and

mental health.

2012 2

Health Effects

From the Housing Health and Safety Rating System Guidance Manual (p. 54):

•Both the detritus from dust mites and mold spores in the home are potent airborne allergens, which can sensitize individuals and trigger allergic symptoms such as rhinitis, conjunctivitis, eczema, cough and wheeze.

•For a person sensitized to these allergens, repeated exposure can cause asthma, the severity of which intensifies with increasing humidity.

2012 3

Potential for Harm

• The most vulnerable age group is all persons

14 years of age and younger.

• Recent research has shown that low levels of

ventilation, without visible mold or dampness,

can result in high indoor humidity levels and

in greatly increased house dust mite

populations.

2012 4

What to look for:• Roof condition (one year out)

• Flashing issues

• Gutters, downspouts, downspout extenders.

• Slope of yard

• Drainpipe back up

• Windows opening in bathroom and kitchen

• Vents in bathroom and kitchen

• Dryer is properly vented

• Leaks in appliances and pipes

• Presence of running water

• Ask the client! (Consider the weather)

Connecting the Hazards

• Deficiencies that affect mold, such as leaks,

and lack of water supply can also affect:

• Domestic Hygiene

• Personal Hygiene

• Water Supply

• Lead

• Structural

2012 13

Damp and mold growthAverage likelihood and health outcomes for all persons aged 14 years or under, 1997-1999, in the UK1

Dwelling type and age Average

likelihood

(1 in...)

Spread of health outcomes Average

HHSRS scores

Class I Class II Class III Class IV

Non HMOs Pre 1920 446 0.0 1.0 10.0 89.0 11 (I)

1920-45 400 0.0 1.0 10.0 89.0 12 (I)

1946-79 446 0.0 1.0 10.0 89.0 11 (I)

Post 1979 725 0.0 1.0 10.0 89.0 7 (J)

HMOs Pre 1920 430 0.0 1.0 10.0 89.0 11 (I)

1920-45 219 0.0 1.0 10.0 89.0 22 (H)

1946-79 967 0.0 1.0 10.0 89.0 5 (J)

Post 1979 644 0.0 1.0 10.0 89.0 8 (J)

All Dwellings 464 0.0 1.0 10.0 89.0 11 (I)

Potential for Harm

1Table from HUD Guidance Manual on HHSRS, p. 54.

What to consider in your region for average likelihoods

•Climate—humidity and rainfall•Asthma prevalence•Common house conditions• HVAC systems—forced air furnace in basement can spread mold spores throughout house•Difference between basements and crawlspaces?

What to consider in your region for average outcomes

•Prevalence of asthma•Severity of asthma (e.g. higher hospitalization rates [3X])•Incorrect medication use (dependence on rescue medication)

Common Detroit Conditions

• Can rain buckets and be very humid

• Basements with forced air furnaces

• Larger, older homes more difficult to maintain

and commonly deteriorating (e.g. roofs,

windows, gutters, downspouts, pipes,

sewage/drainpipes back ups)

• 20% asthma rate

• Higher rate of asthma hospitalizations

1. Damp and Mold Growth Likelihood Outcome Class I Outcome Class II Outcome Class 3

Detroit Local Outcomes 0 2.2 31.6

House in good condition (with no gutter problems or leaks) 1 in 320

A. roof leak over carpet or med - large roof leaks 1 in 10

B. Large amt of visible mold in basement 1 in 10

C. Large amt of Visible mold in basement, forced air furnace 1 in 6

large amt of Mold in others areas of house; no active leaks

D. Leaks in attic above bedroom 1 in 18

E. Small roof leak 1 in 18

F. Bathroom window does not open 1 in 56

G. some old carpet 1 in 180

H. BR/LR most affected increase

Old Carpet, poor condition 1 in 56

Few windows open 1 in 100

Person living in basement increase

No water

Detroit Averages

“Class II and III outcomes raised to reflect Detroit’s rainy climate, and the large number of roof and gutter problems found in homes. Detroit has a high asthma rate and a higher hospitalization rate, and dependence on rescue medication that would result in more serious health outcomes from mold. Many homes have very damp basements with forced air furnaces, which lead to mold growth.”

Outcomes Justification:

Hazard Prevalence: National

• Of a sample of 111,806 occupied housing units in the United States:

– 9,007 (8.1%) units had water leakage from inside the structure in the last 12 months.

– 10,963 (9.8%) had water leakage from outside the structure in the last 12 months.

– 90,905 (81.3%) had a clothes dryer.

Source: American Housing Survey, 2009 National Summary Report and Tables http://www.census.gov/prod/2011pubs/h150-09.pdf

2012 18

Hazard Prevalence: Metro Detroit (MI)

• In metro Detroit (1,731,500 units located in Lapeer, Livingston, Macomb, Monroe, Oakland, St. Clair, & Wayne counties):– 159,700 (9.2%) reported water leakage from inside

the structure in the last 12 months

– 213,700 (12.3%) reported water leakage from outside the structure in the last 12 months

– 2,000 (0.1%) had severe problems with upkeep

– 22,100 (1.3%) had moderate problems with upkeep

Source: American Housing Survey for the Detroit metropolitan area, 2003 http://www.census.gov/housing/ahs/files/detroit03.pdf

2012 19

Hazard Prevalence: Oakland (CA)

• In the Oakland region (855,700 units located in Alameda & Contra Costa counties):– 110,300 (12.9%) reported water leakage from inside

the structure within the last 12 months

– 148,400 (17.3%) had water leakage from outside the structure within the last 12 months

– 600 (0.07%) reported severe problems with upkeep

– 18,400 (2.2%) reported moderate problems with upkeep

Source: American Housing Survey for the Oakland metropolitan area, 1998 http://www.census.gov/housing/ahs/files/oakland98.pdf

2012 20

Outcome Data: National

• About 6-10% of the general population are allergic to mold. Among atopic individuals, 15-50% are allergic to mold (Alliance for Healthy Homes, afhh.org/hhe/hhe_mold.htm).– Allergic reactions include runny nose, eye irritation, coughing,

congestion, and exacerbation of existing asthma.

• In 2009, the current asthma prevalence was 8.2% of the U.S. population (24.6 million people).

• The World Health Organization estimated that 44% of the asthma burden worldwide is due to the environment. Therefore, it is estimated that 44% of asthma sufferers –10.8 million people, or 3.6% of the U.S. population – have environmentally attributed asthma.

2012 21

Outcome Data: Metro Detroit (MI)

• The mortality rate for asthma in Michigan was 1.18 per 100,000 in 2006, for a total of 120 deaths.– Using the WHO estimates for environmental asthma, the

mortality rate due to environmental asthmas would be .47 per 100,000.

• The morbidity rate for asthma was 11.1% of children and 10.5% of adults in 2010.– It is estimated that 1,051,800 people have asthma in the state

of Michigan. Of those, 420,720 are estimated to have environmental asthma.

Source: 2006 Annual Report on Asthma Deaths in Michigan http://oem.msu.edu/userfiles/file/Annual%20Reports/AsthmaMort/06AsthmaMortality.pdf

2012 22

Outcome Data: Oakland (CA)

• In Alameda County, CA, the lifetime asthma

prevalence rate is 16.6%.

• The estimated percentage of environmentally

attributed asthma is 7.3% of the population.

2012 23

24

Healthy Home Rating System Project Leadership

2012

Lyke Thompson

Director

CUS/WSU

(313) 577-5209

ad5122@wayne.edu

Angie Sarb

Research Assistant

CUS/WSU

(313) 577-8911

angie.sarb@wayne.edu

David Ormandy

Professorial Fellow

University of Warwick

+44 (0) 76524 936

david.ormandy@warwick.ac.uk