• Dangerous goods may be packed into a single outer packaging, provided that the goods do not require segregation and will not dangerously react with each other.
• Outer packagings must meet all the requirements of the packing instructions for each dangerous good that is packed therein.

An outer packaging may contain more than one item of dangerous goods or other goods only as follows:

• The dangerous goods do not react dangerously with each other or with the other goods;
• The dangerous goods do not require segregation;
• An outer packaging containing Division 6.2 Infectious Substances must not contain other dangerous goods except as provided in Packing Instruction 620 of the International Air Transport Association (IATA) Dangerous Goods Regulations (DGR);
• The inner packaging used for each item of dangerous goods and the quantity contained within it complies with the relevant part of the packing instruction for that item;
• The outer packagings used are permitted by all the packing instructions that apply to each item;
• The package meets the performance tests for the most restrictive packing group of a substance or article contained in the package;
• The quantities of different dangerous goods contained in one outer packaging must be such that “Q” does not exceed the value of 1, where “Q” is calculated using the formula:
  

• where n1, n2, etc., are the net quantities per package of the different dangerous goods and M1, M2, etc., are the maximum net quantities per package for these different dangerous goods according to the List of Dangerous Goods, for passenger or cargo aircraft, as applicable; and

• The following dangerous goods do not need to be considered in calculating the “Q” value:
  • Carbon dioxide, solid (dry ice) UN 1845;
  • Those where Columns J or L of the List of Dangerous Goods indicate “No limit”;
  • Those with the same UN number, packing group, physical state and the same maximum net quantity according to Table 4.2 in the List of Dangerous Goods, provided they are the only dangerous goods in the package and the total net quantity does not exceed the maximum net quantity shown in the List of Dangerous Goods.

Additional requirements for packages containing radioactive material are found the International Air Transport Association (IATA) Dangerous Goods Regulations (DGR) Section 10.5.

The calculated “Q” value must be:

• Rounded up to the first decimal place, and
• Entered on the Shipper’s Declaration.

UN 3316 is not permitted in the same outer packaging with other dangerous goods.

Certain lithium metal and lithium ion batteries are not permitted in the same outer packaging with most other dangerous goods.

For dangerous goods where the maximum quantity per package has a packing instruction reference shown in Column J or L in the List of Dangerous Goods, check and comply with the maximum net quantity per package as shown in the packing instruction.