Let’s start by defining the term “Dangerous Goods”

Dangerous Goods may be pure chemicals, mixtures of substances, manufactured products or articles which can pose a risk to people, animals or the environment, if not properly handled in storage, use or in transport.” 

In the United States, Dangerous Goods are often referred to as “hazmat”, which stands for hazardous material.

The consequences of improperly stored and handled dangerous goods can have very serious consequences, and all persons involved in their handling must not become complacent. They must always check their approved reference material for guidance and restrictions.

Sometimes there are restrictions even on the transport of aircraft parts.  This is because they could sometimes be considered hazardous when transported in a non-installed arrangement.

The improper carriage of Dangerous Goods has led to a number of incidents and accidents.  Perhaps the most sensational one happened to ValuJet, when its flight 592, operated by a McDonnell Douglas DC-9 carrying a total of 110 persons, crashed in the Florida Keys following an in-flight fire. Have a look at the YouTube video below which briefly describes the accident.

Source: https://www.youtube.com/watch?v=V1y_9v2MVx8&t=18s

ICAO and IATA

ICAO, the International Civil Aviation Organisation,  is a specialised agency within the United Nations, which has oversight of international air transport. It is involved in changes to the principles and techniques of international air navigation, and fosters the planning and development of international air transport to ensure safe and orderly growth.

As part of its function, ICAO oversees the regulation for the transport of dangerous goods by air.  On a high level, ICAO regulates this by setting down the broad principles required in one of its Annexes, ICAO Annex 18, entitled “Safe Transport of Dangerous Goods by Air”.  Annex 18 includes the requirement that dangerous goods are carried in accordance with the Technical Instructions for the Safe Transport of Dangerous Goods by Air.

These Technical Instructions, referenced as Doc 9284, amplify the basic provisions of Annex 18 and contain all the detailed instructions necessary for the safe international transport of dangerous goods by air.

National Aviation Authorities and designated agencies oversee that such regulations are implemented and followed on a national level.  

Although the Technical Instructions are the reference literature, they are not very user friendly, and the industry standard reference material is the “Dangerous Goods Practical Guide Book” provided by IATA, the International Air Transport Association. This manual is often referred to as the “IATA Dangerous Goods Regulations manual” or ”DGR manual” for short.

IATA DGR Manual

This document is approved by aviation regulators as an acceptable reference document to be used when accepting or handling dangerous goods. The term you may encounter is that this document is an Acceptable Means of Compliance or AMC.

If an operator opts to refrain from transporting dangerous goods, any carried items must not be classified as Dangerous Goods in the ICAO Technical Instructions or IATA DGR manual.  But if an item is classified as a dangerous good, they must be carried in limited quantities as outlined in these documents.

An air transport operator can only transport dangerous goods upon the approval by the relevant authority.