I. Overview and experience of the event
At 19:45 on May 29, 1958, a blasting project of the first company of a city's Construction Engineering Bureau was accidentally exploded, causing a particularly serious tragedy of 241 people killed and wounded, including 10 people killed and 19 seriously injured. 212 people.
The rubber plant of the traffic repairing plant built by the Sixth Team of the First Construction Company has a 6.2-meter-high, 19-foot-wide and 18-meter-long epthymite Xiaoshishan, which affects the construction of the main building. They use the “medium-sized cavern drug package method”. Blow up the mountain. When determining the blasting, the personnel must evacuate the warning zone within 500 meters, use the red flag as the point gun, and reduce the flag as the removal warning. Packed with ammonium nitrate explosives of 200 kilograms and black powdered iron of 150 kilograms. When the guns were installed, they were illuminated by hand. Three blasting points were set up. The fuses were connected to the left and right sides of the left and right tunnels and the right and the lower chambers were combined to pull out the openings. The fuse is fired, but because the position of the three bags applied and the distance between the holes are different, the length of the hole exposed by the fuse is not the same, which causes the explosive package to explode at the same time.
At 18:59 on May 29, by the foreman Tang, the first shot was fired at 19:17. After about 5 minutes, the blasters and the construction site leaders mistakenly believed that the three explosion points had exploded at the same time, that is, they entered the blasting site to observe the blasting effect. However, all the three drug packs were not inspected. The workers, farmers and their families who watched the explosion saw the blasting personnel entering the scene and they gradually entered the scene. Some workers were ready to clean up the scene and scored 16 points from the first shot. At the time, the second shot was suddenly slammed, causing the catastrophe of 241 casualties on the spot.
Second, the cause analysis of the accident
1. This blasting is obviously in violation of the regulations issued by the State Council on the “Safety Technical Regulations for Construction and Installation Engineering”. It takes 20 minutes after the shooting, before entering the on-site inspection. The gun only sounded for 5 minutes, and the warning red flag had not yet come down. The blasting personnel entered the scene in violation of the rules.
2. The preparation work for the blast was very unscientific. There was no organization command at the scene. After the first shot, the red flag was lowered and the warning was withdrawn in just 7 minutes. This is the main cause of the accident.
3. From the technical point of view, due to the different properties of black powder and ammonium nitrate explosives, it should not be mixed, and it is wrong to not use electric detonation on the detonation method. At the same time, the use of blasting equipment lacks a test system. For example, if the burning speed of the lead wire and the lead wire are connected together to cause a short circuit, whether the three drug packs can be simultaneously exploded, all make a wrong judgment, resulting in paralysis of "all the sound of the cannon sounds." Thoughts that make security measures unprepared are blind.