Do you remember 40 years ago, Dec. 17, 1976?

Families were relaxing as the evening began, and Christmas shoppers were going about their business, when a very loud, earthquake-like, thundering explosion occurred in San Pedro. The SS Sansinena tank ship had exploded in the outer Los Angeles Harbor, berth 46. The time was 7:33 p.m.

The SS Sansinena was a 36-compartment tank ship that was loading bunker fuel ballast, preparing for an 11 p.m. departure. The Liberian tanker, with its mostly Italian crew, had berthed the day before and off-loaded more than 20 million gallons of Indonesian light crude oil. The 810 foot-long, 70,620 dead-weight-ton tank ship was, when launched in 1958, the largest vessel of its kind built in the United States.

The very light breeze made the evening dew dense, which contributed to the formation of the hydrocarbon vapor cloud over the deck of the ship. An unknown ignition source ignited the vapor cloud. The resulting explosion created damage in a radius of six miles and caused the Sansinena to break into pieces. The ship’s heavy steel covering was held together with rivets. The blast popped the rivets like buttons from a coat, casting thousands of one-pound heads of steel through the air. The entire deck and mid-ship deckhouse, about 500 feet long, was lifted into the air aand landed 200 yards away on the dock. A guard shack was crushed, and the body of the security guard inside was never found. The ship’s bow and stern, now in two pieces, lingered, partially submerged in the water, for many weeks. The blast was felt as far away as 45 miles.

Nine people were killed and 46 injured.

As a young Los Angeles city firefighter, just finishing my probationary period, I was assigned to Fire Station 45 near Olympic and Crenshaw boulevards, in the mid-Wilshire area. Within minutes we were dispatched to the explosion in the harbor. As we approached the entrance to San Pedro and traveled along Gaffey Street, I observed shattered glass picture windows in businesses on both sides of the street, glass littering the road. It was a sight I will never forget. We laid out a long hose across an oil-slicked yard, where we worked vigorously to cut off spreading fire before it jumped into the San Pedro Boat Works, where many vessels were moored.

We remained at the fire for three days, where I witnessed heroic rescues and firefighting. While debris rained down and damaged more than 260 pleasure boats in a nearby shipyard, windows aboard the SS Princess Louise shattered and pelted the onboard partygoers with glass. Early on, fire boat firefighters rescued 18 ship personnel from the water, much of it covered with flames and smoke. Loud hissing noises strongly suggested the potential for another explosion.

The firefighters received medals of valor for their courageous rescue efforts. The cleanup took months.

Immediately following the disaster, the Los Angeles Fire Department and United States Coast Guard developed a new regulation and procedure, still in effect today, for rigorous inspection of hazardous cargo coming into the Port of Los Angeles.

Before my retirement seven years ago, the tank ship inspection program was also introduced to the Port of Long Beach by the Long Beach Fire Department, creating a safer overall environment in both ports.

I am proud to have served the citizens of L.A. during my 34-year career with the LAFD. The harbor communities are safer due in part to the coordination of the area maritime security committee comprised of the U.S. Coast Guard, various federal and state agencies and local law enforcement and first responders to prevent or limit the damage from emergencies like the SS Sansinena explosion.

First responders throughout the United States continue daily to answer emergency calls to protect life and property, often without regard to their own safety, and at times make the ultimate sacrifice. I will always remember and be grateful for the tremendous courage I have witnessed over the years and salute their extraordinary commitment to serve.

Lou Roupoli is a retired assistant chief of the Los Angeles City Fire Department.