 It could have been a falling tool. It could have been a breaking electric light bulb, a spark from a telephone, or a semen, smoking. It was. It ignited vapor hanging over the afterdeck of the SS Sancenina in Los Angeles Harbor. The explosion took lives, destroyed the ship, and caused heavy damage to the port facilities. Ballasting was going on. There were holes concealed by paint in vent piping. Shelter deck doors and ullage holes were open. The Elias said port Mifflin, Pennsylvania. Three massive explosions took place while the ship was discharging its cargo of crude oil. The Elias burned and sank with heavy loss of life. Crude oil vapors found a path from a cargo tank to the midship house through holes in vent systems, bulkheads, and drain pipes. Possible ignition sources included gyro equipment, a hot plate, lights, and smoking in areas normally considered safe. The Chevron, Hawaii, Houston, Texas. Fire, explosion, loss of life. Lightning may have ignited vapors that led a trail of flame into a cargo tank. The Elsa Asperger, Delaware Bay. Fire, explosion, loss of life. Vapors in the pump room exploded when an electric light was turned off. The pump room fan was inoperative. All of these disasters have two things in common. All of them occurred aboard crude oil tankers. And all of them might have been prevented if enough people had understood one simple fact. Tanker safety depends on you. Transport of oil by tanker is one of the largest and most important enterprises in the world today. In a year's time, more than 3,000 tank ships carry 1 and 1 half billion tons of crude oil to nearly 400 ports in 100 nations. This all-important task provides irreplaceable fuel for business, transportation, and home heating. It is performed with remarkable efficiency in all ways but one, safety. The sad fact is that loss of life on tankers worldwide has risen 10-fold in recent years. There are two reasons. Inadequate shipboard maintenance and failure to take normal safety precautions. Experts agree that both have one origin. Too few people recognize the many dangers of transporting crude oil. Many people think of crude oil as they would think of tar or asphalt, a thick, heavy substance that normally has to be heated to be pumped. Hardly a substance to be feared. They are dangerously wrong. All oil is basically the same thing, a compound of hydrogen and carbon. Hydrocarbons such as gasoline, kerosene, and propane have differing flash points. The term flash point is easily defined. Liquids don't burn, but vapors do. As the liquid is heated, it gives off vapors. Eventually, it gives off enough vapor when mixed with air to support combustion. The temperature of the liquid at that point is called the flash point. Three things are necessary for fire. Fuel like this crude oil, oxygen, and an ignition source, something to start it. Remove the concentration of vapor by ventilation, and there can be no fire. Remove oxygen, as you see here, and the fire goes out. Remove the ignition source, and no fire is possible. But combine all three, and you get fire. If the fire is contained in an enclosed space, such as a pump room or cargo tank, the fire can become an explosion. There are many possible ignition sources, a spark from a hand tool, a broken light bulb, a defective switch, a faulty hot plate, or an open flame from a match or torch. Safety precautions and shipboard maintenance are interdependent. If an accident causes ignition, an defective flame screen may prevent flames from penetrating into a cargo tank. But a hole the size of a pin can render the flame screen useless. So we need to eliminate the ignition source and employ good maintenance to protect ourselves against accidental ignition. It brought 200,000 barrels of oil to an amicote terminal and refinery. A Coast Guard officer arrives to make a routine safety inspection. Care for routine tank vessel safety inspection? May I see your decoration of inspection? All right, mate. The chief mate and terminal officer have gone through their safety checklist before starting transfer of the cargo. Coast Guard inspector verifies that the proper procedures have been followed. The ship is securely moored and ready to move under its own power if necessary. A bonding cable has been secured ship to shore to eliminate arcing when the hoses are hooked up. Warning signs have been posted ashore and on the ship. Radar and radio equipment have been shut down. Doors, windows, and ports are closed. Ventilators are trimmed to prevent the entry of vapor. Flame screens are inspected. When a faulty one is found, it is replaced on the spot. Smoking on deck is prohibited. There is danger of vapors accumulating on deck or becoming trapped in pockets near the superstructure. Small details cannot be overlooked, nor can larger problems, holes, and vent systems. Loose connections and piping, inoperative ventilator fans, all must be put in order. All of these safety measures are important, whether the ship is loading, unloading, or ballasting. The pump room is the most dangerous place in the ship, since it is there that vapors tend most to concentrate. It must be kept clean and free of flammable liquids in the bilges. Seals and glands must be tight and well maintained. There must be a powerful ventilating system. How long has your pump room ventilation been operating? The blower has been running about 30 minutes now. The inspection is complete and unloading begins. Loading and ballasting are even more hazardous than unloading because they drive large volumes of vapor out of the cargo tanks. Some ship crews try to speed up the process by opening lids and ulages to relieve pressure in the tanks. This allows vapors to accumulate on deck and creates a major safety hazard. Tanks should be vented through the established venting system only. Following these procedures may seem unnecessary when no danger seems to be visible or present, but the need for them has been established by hard experience. Remember the Sancenina, remember the Elsa S. Berger, remember the experience of the United States Coast Guard. Our duty is to enforce all federal laws and international treaties in the navigable waters of the United States and to conduct the inspections necessary to carry out that duty. Our mission is safety. The rules we ask you to observe and the advice we offer and exchange with you are based on years of mutual experience in the design, maintenance, and handling of seagoing vessels. Tanker safety requires a unique kind of democracy in which every man's life depends on the efficiency of every other man aboard. No matter how careful others may be, any man from master to seaman can destroy a ship simply by lighting a cigarette or failing to repair a vent or close a lid. And any man from seaman to master can take that one step that protects his ship, his shipmates, and himself from disaster. You will be safe only when you realize one simple fact. Tanker safety depends on you.