For the review of federal Occupational Safety and Health Administration OSHA records reported in this Inside Climate News article, we scraped records of farmworker fatalities in California from 2018 to 2022 from OSHA's accident search site.

We also scraped records of employer citations for violations of California's standard for heat illness prevention in outdoor places of employment from OSHA's industry search site.

For both scrapes, we identified farmworkers and agricultural employers using the following North American Industry Classification System (NAICS) codes: 1111, 1112, 1113, 1114, 1119, 115.

For each fatality, we obtained temperature data for the time and location of the incident (or 12.00 noon local time on that day if no time was recorded), plus records of the maximum temperature over each of the preceding four days using the OpenWeatherMap One Call API 3.0.

For each fatality, we also obtained records of the 24-hour PM2.5 Air Quality Index recorded by the nearest monitoring station in the federal Environmental Protection Agency's Air Data network for the day of the incident, or the nearest prior day for which data was available.

Email Peter Aldhous at peter.aldhous@insideclimatenews.org.