Dangerous Goods Classifications & Risk Categories
Dangerous goods and hazardous materials and chemicals are classified under different risk categories and require expertise and specialised teams when transporting and storing them.
DANGEROUS GOODS CLASSIFICATIONS
Dangerous goods, (abbreviated as DG) are items or substances that when transported are a risk to health, safety, property or the environment.
Hazardous materials (abbreviated as HAZMAT or hazmat) are substances, solids, liquids, or gases that can harm people, other living organisms, property, or the environment, more specifically.
Hazardous materials are often subject to chemical regulations. Hazmat teams are personnel specially trained to handle dangerous goods, which include materials that are radioactive, flammable, explosive, corrosive, oxidizing, asphyxiating, bio hazardous, toxic, pathogenic, or allergenic. Also included are physical conditions such as compressed gases and liquids or hot materials, including all goods containing such materials or chemicals, or may have other characteristics that render them hazardous in specific circumstances. Mitigating the risks associated with hazardous materials may require the application of safety precautions during their transport, use, storage and disposal.
Dangerous goods are divided into nine classes (in addition to several subcategories) on the basis of the specific chemical characteristics.
Class 1 : Explosives
Class 2 : Flammable Gas
Class 3 : Flammable Liquids
Class 4 : Flammable Solids
Class 5 : Oxidizing Agents and Organic Peroxides
Class 6 : Toxic and Infectious Substances
Class 7 : Radioactive substances
Class 8 : Corrosive
Class 1 : Explosives
Class 2 : Flammable Gas
Gases which are compressed, liquefied or dissolved under pressure as detailed below. Some gases have subsidiary risk classes; poisonous or corrosive.
2.1 Flammable Gas: Gases which ignite on contact with an ignition source, such as acetylene, hydrogen, and propane.
2.2 Non-Flammable Gases: Gases which are neither flammable nor poisonous. Includes the cryogenic gases/liquids (temperatures of below -100 °C) used for cryopreservation and rocket fuels, such as nitrogen, neon, and carbon dioxide.
2.3 Poisonous Gases: Gases liable to cause death or serious injury to human health if inhaled; examples are fluorine, chlorine, and hydrogen cyanide.
Class 3: Flammable Liquids
Flammable liquids included in Class 3 are included in one of the following packing groups:
• Packing Group I, if they have an initial boiling point of 35°C or less at an absolute pressure of 101.3 kPa and any flash point, such as diethyl ether or carbon disulfide;
• Packing Group II, if they have an initial boiling point greater than 35°C at an absolute pressure of 101.3 kPa and a flash point less than 23°C, such as gasoline (petrol) and acetone; or
• Packing Group III, if the criteria for inclusion in Packing Group I or II are not met, such as kerosene and diesel.
Class 4: Flammable Solids
Solid substances that are easily ignited and readily combustible
4.1 Flammable Solids: Solids substances that are easily ignited and readily combustible (Nitrocellulose, magnesium.)
4.2 Spontaneously combustible : Solid substances that ignite spontaneously (aluminium Alkyls, White Phosphorus)
4.3 Dangerous when wet : Solid substances that emit a flammable gas when wet or react violently to water. (Sodium, calcium, potassium, calcium carbide).
Class 5: Oxidizing Agents and Organic Peroxides
These are oxidizing agents other than organic peroxides
5.1 Oxidizing agents other than organic peroxides( calcium hypochlorite, ammonium nitrate Hydrogen peroxide, potassium permanganate).
5.2 Organic peroxides, either in liquid or solid form (benzoyl peroxides, cumene hydro peroxide).
Class 6: Toxic and Infectious Substances
Substances that are liable t cause death or serious injury
6.1 Toxic substances which could cause death or serious injury if ingested or absorbed by by the skin.
6.2 Bio hazardous substances; the WHO divides this class in two i.e.
Category A – Infectious
Category B – Samples ( virus cultures, pathology specimens, used intravenous needles )
Class 7: Radioactive substances
Radioactive substances comprise of substances or a combination of substances which emit ionizing radiation (uranium, plutonium).
Class 8: Corrosive
Corrosive substances are substances that can dissolve organic tissue or severely corrode certain metals
8.1 ACIDS: sulphuric acid, hydrochloric acid
8.2 ALKALIS: potassium hydroxide, sodium hydroxide
Class 9: Miscellaneous
Hazardous substances that do not fall into other categories (asbestos, air-bag inflators, self-inflating life rafts, dry ice).