Faculty Publications

Publication Date

April 2009


This pilot research was undertaken to discover barriers that prevent homeowners from mitigating earthquake hazards in their homes. There is a relatively significant body of literature on disaster mitigation, which is reviewed and summarized in this report. However, no studies address how these barriers may be overcome so that homeowners would be more proactive in mitigation. If the barriers can be identified, then future communications and policy actions that address these barriers can be taken, resulting in more widespread mitigation implementation that reduces the injury and damage potential that communities face, leading to a reduction in the post-disaster response requirement, and the time required to achieve recovery.

Data came from an online survey of San José State University employees; the survey took approximately 15 minutes for respondents to complete. Questions addressed home characteristics, demographic characteristics, perceptions of earthquake risk, levels of mitigation, past experience with earthquake injury or damage, social influences on hazard and damage prevention, and reactions to various incentives. Statistical analyses were done using SPSS version 16.0.

Of the total 331 respondents, 215 were homeowners and consequently used for data analysis. Of these homeowners, 79 % owned single-family homes. The sample overwhelmingly expects a major earthquake to occur within the next 10 years, and most expect to suffer earthquake-caused injuries and damage within their homes in the near future.

The findings indicate the importance of earthquake expectations and the social network for influencing mitigation. Physical proximity to others who experienced earthquake damage and relational closeness to those who have taken mitigation actions were found to have a positive effect on mitigation implementation by individuals. Homeowners assumed responsibility for mitigation, and cost is generally not a concern. The most prevalent obstacles to mitigation were the feeling that the mitigation is not necessary or that it is inconvenient. Home structures and systems mitigation is far more commonplace than home contents mitigation. Mitigation of home contents was perceived as not being very important, and this perception prevents individuals from taking mitigation actions.

All incentive types that were presented to respondents, which were primarily financial in nature, were reported as likely to increase mitigation. Providing advice and information was also reported to likely result in higher levels of mitigation. The development of mitigation approaches that are low-cost and simple is expected to have a positive effect on mitigation actions. In addition, codes were found to be effective at prompting mitigation – most respondents had mitigated for items that have code requirements. One outcome of this is that mitigation of structures is more widely reported than mitigation of home contents.

More research is needed to explore non-financial incentives for mitigation, including incentives provided by personal relationships and how social relationships may be leveraged. There is also a need to explore whether different types of incentives (such as free labor or education) would be more or less effective at prompting particular mitigation actions (such as securing the foundation or strapping down appliances). It would be helpful to take a “bottom up” approach by conducting focus groups on these topics.

Demographic effects on mitigation and barriers to mitigation also need to be explored further. There were suggestions that demography mattered, but the sample size for this survey was not sufficiently large to draw statistically valid conclusions. There is also a need to revise the survey instrument to remove some ambiguities and inadequacies that currently exist. It would be useful to explore why persons might have taken particular mitigation actions and how social networks affect their mitigation action, among other things.

Heightened perceptions of earthquake threats, experience with earthquake injuries and damage, and social relationships are critical predictors of mitigation. Individuals who know others who have mitigated are more likely to mitigate; therefore improved communications, on the personal level, on the topic of mitigation can be effective. Given the perceptions of mitigating home contents, the public also needs to be made more aware of the threats posed by home contents during an earthquake.