Martin Blank died on June 13 at the age of 85.

A retired professor at Columbia University, Blank was a long-time EMF researcher, best known for his collaboration with Columbia’s Reba Goodman.

Writing in his 2014 book, Overpowered, Blank called himself an “unlikely activist” and urged people to practice precaution.

His obituary is posted on the Web site of the EMF Safety Alliance.