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Safety 493: Air Pollution: Air Pollution Disaster assignment

An online research guide for use with Prof. Vosburgh's Safety 493 class

Primary vs. Secondary

In researching a historical incident like this one, it is important to understand the difference between primary and secondary resources. 

Primary: Secondary:
Recorded by people who experienced events firsthand Recorded sometimes months/days/years after the events

Benefits: Immediacy. "Raw details" of event that provide fodder for later analysis. 

Drawbacks: Often inaccurate or incomplete picture. No long-term perspective.

Benefits: Long-term perspective usually allows more indepth analysis of effects, significance, etc.

Drawbacks: Events are sometimes clouded by bias or agenda. 

Examples: Photos. Video. Diaries or journals. Interviews. Newspaper accounts of survivors/witnesses. Social media. (Some) books. Examples: Scholarly journal articles. (Most) books. Many popular magazine and newspaper articles. Some video.

Depending on your disaster, you may find many primary and secondary sources just via Google. But if so, try to use sources that focus on the air-quality issues surrounding the disaster. In addition, you need to evaluate carefully whether web sources are reliable -- anybody can post anything on the web. Look for indicators of reliability such as: 

  • Named authors, preferably authors with a background in safety/health/pollution/environment/etc., or a respected organization as an author (e.g. the Environmental Protection Agency)
  • Being authorized or presented by a known-reliable source (e.g. established news sources, government agencies, statistics-collecting agencies)
  • Naming the sources of the information (other researchers, identifying who took the picture/video, identifying a survey or statistic)
  • Look at the date of publication -- these are historic events so current date is not as important, but the date can be a clue whether you're looking at a primary or secondary source

Primary Sources

U.S.-based historical sources: 


Any location:

Secondary Sources

Secondary analysis could come from multiple different perspectives -- for example, how did the Krakatoa disaster affect people's health, geologic understanding, urban development, agriculture, government's role in citizen safety, etc.... the options are endless. 

Thus, your secondary sources will be most helpful to you if they look at it from a safety and health perspective, as specific to air quality as possible. Try the databases below for health, environment, or business-related perspectives: 


These databases contain documentary video. Depending on your disaster, there may be either primary or secondary documentaries that provide compelling video footage of the disaster. 

Use the Embed codes on the page in order to embed the video into your PPT presentation. 

If you use them, be sure to cite images or video just as you would cite a print source -- see this page for examples.