POR-200-06
Ce résumé est également disponible en français
Prepared for the:
Meteorological Service of Canada
Environment Canada
enviroinfo@ec.gc.ca
October 2007
Contract # KW203-060585/001/CY
Awarded 2006-12-08
336 MacLaren Street
Ottawa, ON K2P 0M6
The results of this research reveal that the air quality advisory issued during the poor air quality event in the City of Windsor in late August 2007 had relatively modest impact on local residents, in terms of attracting attention and prompting actions to reduce personal exposure. It is notable that the advisory did not have a greater impact since residents in this city are sensitized to local air quality in comparison with those living in the other Canadian cities covered through this research. Windsor residents have a very poor view of local air quality generally, feel that poor air quality has a significant adverse effect on health and are reasonably familiar with the Air Quality Index (AQI).
These findings suggest that even in communities where air quality is widely recognized as poor, air pollution is considered just one of the many risks of living in urban centres and not worthy of residents’ attention unless they are confronted with evidence more compelling than what is presented in a typical air quality advisory. It may also be that perceptions of general air quality in the Windsor area are so poor that periods of measurably worse air quality do not stand out.
Overall, the broad patterns of opinion and behaviour observed are generally consistent with those seen in previous post-event air quality surveys conducted in various regions of Canada over the past few years.
The survey conducted with City of Detroit residents reveals a starkly different picture. Residents in this metropolitan area are markedly positive about local air quality conditions (compared with Windsor and most other Canadian locations previously surveyed), and few noticed any deterioration in conditions during the period of poorer air quality in the days preceding the survey. Only three in ten recall any air quality advisories over the previous two years.
Detroit residents are also noticeably less concerned about the health effects of poor air quality, although they are as likely as Windsor residents to feel that even low levels of pollutants can cause health problems.
The other striking difference between the two cities is in their response to advisories recalled. Windsor residents tend to report taking actions to protect their health (e.g., stayed indoors, reduced strenuous activity), but Detroit residents who recalled past advisories emphasized steps taken to reduce their contribution to the problem (e.g., reduced driving).
The following provides key highlights from the study with City of Windsor and City of Detroit residents regarding air quality in their community.
WINDSOR
Residents of Windsor are quite negative about air quality conditions in their community. More than three-quarters of residents believe that, as a rule, air quality in Windsor is only fair (31%) or poor (46%), compared to less than one-quarter who rate it as good (21%) or excellent (2%). Ratings of local air quality conditions became slightly more positive during the time that the advisory was in effect—with roughly four in ten residents saying that air quality was good, or better, as actual air quality conditions deteriorated.
Although more than three-quarters of residents say they regularly or occasionally pay attention to local air quality conditions during the summer, most claim to rely on first-hand observation of poor air quality—e.g., seeing it in the air (32%), feeling its effects on breathing (27%) and smelling it (21%)—while relatively few rely on the public information provided by weather reports (25%) and air quality advisories (12%).
The belief that air pollution poses a serious health hazard is held by most Windsor residents (85%) and most identify respiratory illnesses as the likely health consequence of air pollution (81%).
DETROIT
Generally, residents of Detroit are quite positive about air quality in their community, with more than seven in ten residents rating the usual air quality in their city as excellent (24%) or good (48%) and roughly one quarter rating it as only fair (20%) or poor (6%). Although quite positive as a rule, perceptions of local air quality became even more positive in the days preceding the survey, with more than eight in ten saying that air quality was good, or better, during that period.
Half the residents of Detroit report paying regular or occasional attention to local air quality conditions at this time of year, though very few claim to rely on weather reports (14%) or air quality advisories (2%) as sources of information.
As with the attention they pay to local air quality conditions, residents of Detroit are mixed as to the extent to which air pollution presents a health hazard in their area: one-half believe that air quality is not a serious hazard, while more than four in ten (44%) believe that it is. Although mixed as to its status as a health threat, when pressed, a strong majority of residents (76%) believe that the most likely health consequence of air pollution is respiratory illness.
WINDSOR
Roughly three in ten (29%) Windsor residents claim to have seen or heard an announcement or information about poor air quality in the days prior to the post-event survey. When asked what it is was that they heard, the top responses include a warning about poor air quality in the area (63%), information about the Air Quality Index (47%) and a “smog alert” (31%). Those who saw or heard an announcement are most likely to identify television (55%) or radio (45%) as their source, and they are most likely to report simply happening upon it (72%) as opposed to seeking it out (28%).
Roughly half (53%) of those who heard the advisory claim to have discussed it with others, although only four in ten claim to have personally (or within their household) done anything differently as a result of the advisory. The most common actions reported include reducing time outdoors and closing windows around the home.
The top three reasons given by those who heard the advisory, but did not do anything differently, include being unable to make any changes (24%), believing that there was nothing that they could reasonably do differently (19%) or feeling that no changes were necessary since the air was not that bad (13%).
Although only one-third of residents who heard the advisory claim to have done anything differently, more than four in ten (42%) believe that they or someone in their household may have experienced a physical or health problem due to poor air quality during the days in which the advisory was in effect. This is a substantially higher figure than those seen in recent post-event surveys.
Among residents who did not hear the recent advisory, three-quarters (73%) report hearing one at some point during the past two years.
DETROIT
WINDSOR
Residents of Windsor show a reasonably high level of awareness about the Air Quality Index for their area, with more than six in ten saying they are either very (21%) or somewhat (41%) familiar with it. Although there are two indices in their area—the Windsor AQI and the Detroit-Michigan AQI—Windsor residents are most likely to report being familiar with the Windsor index. Among those who describe themselves as familiar with at least one of the indices in their area, three-quarters report consulting the index at least occasionally during the summer months.
Residents who are most familiar with the Windsor AQI tend to recognize the word scale version of the index (83%) more readily than either the colour scale (52%) or the numeric scale (44%). Those who recognize more than one scale tend to believe that the word scale version is most useful.
One of the purposes of air quality advisories is to inform people about the health impacts associated with air pollution and to recommend how people can limit their exposure. When asked how well advisories perform this function, seven in ten Windsor residents take the view that they are either very (31%) or somewhat (40%) effective. Those who find the advisories ineffective are most likely to identify the lack of viable choices (26%), a perceived lack of general concern about advisories (25%) or the fact that people are simply not going to change with or without advisories (18%) as the primary shortcomings of air quality advisories.
DETROIT
Familiarity with the local air quality indices is limited in Detroit, with fewer than half of residents reporting that they are very (8%) or somewhat familiar (38%) with them. Those reporting familiarity with the AQI are most likely to report following the Detroit-area AQI (61%). Claims of familiarity among Detroit residents may be overstated: roughly one-quarter (24%) of those reporting familiarity with local air quality indices say they are familiar with neither the Detroit- or Windsor-area AQI. Among those who describe themselves as familiar with at least one of the indices in their area, half say they consult the index at least occasionally during the summer.
Residents of Detroit who are most familiar with the Detroit-Michigan area AQI are more likely to be familiar with the word scale version (72%) than with either the colour scale (53%) or the numeric scale (15%) versions.
Despite very low recall of any air quality advisory during the past two years, well over half the residents of Detroit believe that advisories are very (21%) or somewhat (40%) effective when it comes to telling people about the health impacts of air pollution and recommending ways of limiting exposure.
At a general level, the findings reported do not vary widely across the population, as defined by demographic characteristics, health status or general attitudes. As we have seen in past studies, the most notable distinction can be found among a minority of the population who appear to be “sensitized” to poor air quality. This group includes those who regularly pay attention to air quality conditions and actively seek out AQI information, and who are also most likely to report taking action in response to the recent advisory. Contrary to expectations, the results indicate that personal health status and presence of key health problems in the household (such as respiratory or heart disease) have a relatively limited impact on awareness of the recent advisory or familiarity with the AQI.