Disasters that Built Process Safety: Seveso (1976)

This paid post is the third in a six-part series that describes disasters that led to the formation of the Process Safety Management (PSM) discipline.

The Series

The posts in this series are:

1. Flixborough (1974)

2. Bhopal (1984)

3. Seveso (1976) (this one)

4. Piper Alpha (1988)

5. Toulouse (2001)

6. Texas City Refinery (2005)

What Happened

On July 10, 1976, a major industrial accident occurred in Seveso, a small town near Milan, Italy. The release took place at a chemical plant operated by ICMESA (a subsidiary of Givaudan, owned by Hoffmann–La Roche). The facility was producing trichlorophenol, an intermediate used in herbicides and disinfectants.

As a result of a runaway reaction, a large cloud of toxic chemicals, notably 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), one of the most poisonous dioxins known, was vented into the atmosphere.

The accident was the result of several technical and organizational failures:

Runaway Exothermic Reaction