Hazardous chemicals in the current management measures are divided into eight categories, as follows:

1 class, explosives;

This kind of chemicals refers to the articles that can react violently under the external action (such as heating, friction, impact, etc.). ), instantly produce a lot of gas and heat, so that the surrounding pressure rises sharply, causing an explosion, thus causing damage to the surrounding environment. It does not include articles with no overall explosion danger, but with burning, throwing and slight explosion danger.

The second category, compressed gas and liquefied gas;

Refers to the gas dissolved by compression, liquefaction or pressure, and meets one of the following two conditions:

1, the critical temperature is lower than 50℃, or the vapor pressure is greater than 294kpa at 50℃

2. Compressed gas whose absolute pressure is greater than 257kpa at 265438 0.2℃ or 765438±05 kpa at 54.4℃; Or liquefied gas or pressurized dissolved gas with Reed vapor pressure greater than 275kpa at 37.8℃.

When this kind of goods are heated, hit or strongly vibrated, the pressure in the container will rise sharply, which will lead to the explosion of the container, or the valve of the gas cylinder will loosen and leak, resulting in a fire or poisoning accident. According to its nature, it is divided into the following three items: combustible gas; Noncombustible gas (including combustion-supporting gas); Toxic gas.

Class 3, flammable liquids;

Refers to liquids, liquid mixtures or liquids containing solid substances whose closed cup flash point is equal to or lower than 6 1℃, but does not include liquids that have been classified in other categories because of their danger. This substance is volatile at room temperature, and its vapor can form an explosive mixture when mixed with air.

According to flash point, it is divided into the following three items: 1, flash point of low flash point liquid.

Class 4, flammable solids, spontaneous combustion articles and flammable articles when wet;

1. Flammable solids: refer to solids with low ignition point, sensitive to heat, impact and friction, easily ignited by external fire sources, burning rapidly, and possibly emitting toxic fumes or gases;

2. Spontaneous combustion articles: refers to articles with low spontaneous combustion point, which are prone to oxidation reaction in air, release heat and burn by themselves;

3. Flammable articles in contact with moisture: refers to articles that undergo violent chemical reactions when in contact with water or moisture and release a large amount of flammable gas and heat. Some will burn or explode without an open flame.

Category 5, oxidants and organic peroxides;

This kind of articles has strong oxidation and is easy to cause combustion and explosion. According to its composition, it is divided into the following two items:

1, oxidant refers to a substance which is in a high oxidation state, has strong oxidation and is easy to decompose and release oxygen and heat. Including inorganic substances containing peroxy groups, which are not necessarily flammable, but can cause the combustion of combustible materials; It can form explosive mixture with powdery combustible materials and is sensitive to heat, vibration or friction. According to its danger, it can be divided into primary oxidant and secondary oxidant.

2. Organic peroxides refer to organic substances with peroxy bonds in their molecular composition, which are flammable, explosive and easily decomposed, and are extremely sensitive to heat, vibration and friction.

Category 6, toxic and infectious substances;

Refers to the articles that accumulate to a certain amount after entering the body, can have biochemical or biophysical effects with body fluids and tissues, disturb or destroy the normal physiological functions of the body, cause temporary or permanent lesions, and even be dangerous and life-threatening.

Specific indicators: oral LD50≤500mg/kg (solid) LD50≤2000mg/kg (liquid) percutaneous (24-hour contact): LD50≤ 1000mg/kg (solid) inhalation LC50≤ 10mg/L (dust and smoke) This category is divided into toxic substances and infectious substances. Among them, toxic substances are divided into a class of toxic substances and a class of toxic substances according to their toxicity.

Class 7, radioactive substances;

There are many ways to classify radioactive substances, and the following are commonly used.

1, physical form can be divided into: solid radioactive substances, such as cobalt 60, monazite, etc. ; Powdered radioactive substances: such as noctilucent powder, cerium sodium double salt, etc. Liquid radioactive substances: such as luminescent agent, medical isotope preparation sodium dihydrogen phosphate -P32, etc. Granular radioactive substances: such as thorium nitrate; Gaseous radioactive materials: such as krypton 85 argon 4 1 etc.

2. According to the types of radiation, it can be divided into: radioactive substances that emit α, β and γ rays, such as radium 226; Radioactive substances that emit alpha and beta rays; Such as natural uranium; Radioactive substances that emit beta and gamma rays: such as cobalt 60; Radioactive articles that emit neutron streams (one or two of α, β or γ rays at the same time), such as radium beryllium neutron streams, polonium beryllium neutron streams, etc.

3, according to the radioactive size is divided into primary radioactive substances, secondary radioactive substances, tertiary radioactive substances.

Class 8, corrosive products.

Corrosive products refer to solids or liquids that can burn human tissues and cause damage to metals and other objects. Necrosis can be seen within 4 hours after skin contact, or solid or liquid with uniform annual corrosion rate greater than 6.25mm/a on No.20 steel at 55℃.

This kind can be divided into three items according to chemical properties: acidic corrosion products; Alkaline corrosive products; Other corrosive products. According to its corrosiveness, it can be divided into first-class corrosive agent and second-class corrosive agent.