John Harold Large (1943 – 3 November 2018) was an English consulting Chartered Engineer primarily. He was known for his work in assessing and reporting nuclear safety and nuclear related accidents and incidents, work which has often featured in the media.
He provided technical evidence in the Friends of the Earth legal action over the failure of the steam generators of the Southern California San Onofre Nuclear Generating Station in 2013.
Large died on 3 November 2018 from a heart attack at the age of 75.