Also known as the UN packing group, dangerous goods or DG packaging is divided into 3 groups. This DG packaging group aims to differentiate the levels of danger or hazard that these goods possess in terms of physical and chemical properties. The following are the groups:
- High danger or Packing Group I
- Medium danger or Packing Group II
- Low danger or Packing Group III
Importance of DG packaging groups
These packing groups are important because it dictates the degree of packaging required for transporting dangerous goods. These groups are the basis of specification marks written in packaged and containers used to DG shipping.
Let’s check out the specific packing groups used for the specific classes in the dangerous goods classification table (as stated on www.chemsafetypro.com):
- Class 3 Flammable Liquids
- Packing Group I: Assigned to flammable liquids with an initial boiling point less-than-or-equal-to 35°C.
- Packing Group II: assigned to flammable liquids with a flashpoint less-than-or-equal-to 23°C and an initial boiling point of greater than 35°C.
- Packing Group III: Assigned to flammable liquids with a flashpoint greater-than-or-equal-to 23°C but less-than-or-equal-to 60.5°C and an initial boiling point of greater than 35°C.
- Class 4 Division 4.1 Flammable Solids
- Packing group II: Assigned to readily combustible solids (other than metal powders) if the burning time is less than 45 seconds and the flame passes the wetted zone or assigned to powders of metal or assigned to metal alloys if the zone of reaction spreads over the whole length of the sample in 5 minutes or less.
- Packing group III: Assigned to readily combustible solids (other than metal powders) if the burning rate time is less than 45 seconds and the wetted zone stops the flame propagation for at least 4 minutes or assigned to metal alloys if the reaction spreads over the whole length of the sample in more than 5 minutes but not more than 10 minutes.
- Class 4 Division 4.2 Substances Liable to Spontaneous Combustion
- Packing Group I: Pyrophoric liquids and solids.
- Packing Group II: if a self-heating material gives a positive test result when tested with a 25 mm cube size sample at 140°C;
- Packing Group III: Packing group III must be assigned to self-heating substances if:
(a) a positive result is obtained in a test using a 100 mm sample cube at 140 °C and a negative result is obtained in a test using a 25 mm cube sample at 140 °C and the substance is to be transported in packages with a volume of more than 3 m3;
(b) a positive result is obtained in a test using a 100 mm sample cube at 140 °C and a negative result is obtained in a test using a 25 mm cube sample at 140 °C, a positive result is obtained in a test using a 100 mm cube sample at 120 °C and the substance is to be transported in packages with a volume of more than 450 liters;
(c) a positive result is obtained in a test using a 100 mm sample cube at 140 °C and a negative result is obtained in a test using a 25 mm cube sample at 140 °C and a positive result is obtained in a test using a 100 mm cube sample at 100 °C. if a positive test result is obtained on a self-heating material in a test using a 100 mm sample cube at 140°C, 120°C or 100°C depending on packaging volume;
- Class 4 Division 4.3 Substances Which, in Contact with Water, Emit Flammable Gases
- Packing Group I: if the material reacts vigorously with water at ambient temperatures and demonstrates a tendency for the gas produced to ignite spontaneously, or which reacts readily with water at ambient temperatures such that the rate of evolution of flammable gases is equal or greater than 10 L per kilogram of material over any 1 minute;
- Packing Group II: if the material reacts readily with water at ambient temperatures such that the maximum rate of evolution of flammable gases is equal to or greater than 20 L per kilogram of material per hour, and which does not meet the criteria for Packing Group I; or
- Packing Group III: if the material reacts slowly with water at ambient temperatures such that the maximum rate of evolution of flammable gases is greater than 1 L per kilogram of material per hour, and which does not meet the criteria for Packing Group I or II.
- Class 5 Division 5.1 Oxidizing Substances
- Packing Group I, for any material which, in either concentration tested, exhibits a mean burning time less than the mean burning time of a 3:2 potassium bromate/cellulose mixture.
- Packing Group II, for any material which, in either concentration tested, exhibits a mean burning time less than or equal to the mean burning time of a 2:3 potassium bromate/cellulose mixture and the criteria for Packing Group I are not met.
- Packing Group III for any material which, in either concentration tested, exhibits a mean burning time less than or equal to the mean burning time of a 3:7 potassium bromate/cellulose mixture and the criteria for Packing Group I and II are not met.
- Class 5 Division 5.2 Organic Peroxides
- Packing Group II. All Division 5.2 materials are assigned to Packing Group II.
- Class 6 Division 6.1 Toxic Substances
- Packing group I: Substances and preparations presenting a very severe toxicity risk
- Packing group II: Substances and preparations presenting a serious toxicity risk
- Packing group III: Substances and preparations presenting a relatively low toxicity risk.
- Class 8 Corrosive Substances
- Packing Group I: Materials that cause full thickness destruction of intact skin tissue within an observation period of up to 60 minutes starting after the exposure time of three minutes or less.
- Packing Group II: Materials other than those meeting Packing Group I criteria that cause full thickness destruction of intact skin tissue within an observation period of up to 14 days starting after the exposure time of more than three minutes but not more than 60 minutes.
- Packing Group III: Materials, other than those meeting Packing Group I or II criteria but cause full thickness destruction of intact skin tissue or exhibit corrosion on either steel or aluminum surfaces exceeding 6.25 mm (0.25 inch) a year.
- Class 9 Miscellaneous Dangerous Goods
- Packing Group II: Lithium batteries, lithium batteries packed with equipment, lithium batteries packed with machinery.
- Packing Group III: The UN packing group, where applicable, of Class 9 goods is specified in the UNECE dangerous goods list. With the exception of lithium batteries, all Class 9 articles and substances with a UN Packing Group are assigned to Packing Group III.