Irwin Isaacson Jr., an engineer who worked on such New Orleans landmarks as the Superdome, the International Trade Mart and the Rivergate, died Wednesday at Touro infirmary after a heart attack.

He was 91.

Isaacson was the president and chairman of Weil and Moses Inc., which was founded by his uncle, Walter Moses. The company was involved in the design of the electrical systems for the Dome, known now as the Mercedes-Benz Superdome.

The Trade Mart was later renamed the World Trade Center. The Rivergate, a modernistic exhibition and convention space near the foot of Canal Street, was torn down to build Harrah’s Casino.

Isaacson later was chairman of IMC Consulting Engineers.

The author Walter Isaacson, whose books include biographies of Albert Einstein and Apple founder Steve Jobs, once described his father as a “kindly Jewish distracted humanist engineer with a reverence for science.”

Irwin Isaacson’s younger son, Lee, a computer consultant, credited his father for passing on his interest in science, technology and math to his sons.

Irwin Isaacson graduated from Fortier High School and Tulane University, where he earned a degree in mechanical engineering. He served in the Navy from 1944 to 1946.

Lee Isaacson said that even though his father’s degree was in mechanical engineering, he worked mostly as an electrical or consulting engineer.

Irwin Isaacson was a former member of the boards of the Alliance for Affordable Energy, Touro Infirmary, the Jewish Community Center and the Broadmoor Improvement Association, where he served terms as vice president and co-chairman.

He also served on the city's Board of Electrical Examiners and a committee to write a new building code for New Orleans.

In addition to his two sons, survivors include his wife, Julanne Isaacson; a stepson, Tom Haspel; two stepdaughters, Katherine and Judith Haspel; a sister, Marjorie Bissinger; a granddaughter; and five stepgrandchildren.

A funeral will be held at 1 p.m. Sunday at Temple Sinai, 6227 St. Charles Ave. Visitation will begin at noon. Burial will be private.