由 caicai8478 In the international logistics field, air freight is renowned for its efficiency and speed. However, for powder cargo, air freight has the highest entry barriers. A shipment of ordinary powder might be easily transported by sea, but if planned for air freight, it could face rejection, stringent packaging requirements, or exorbitant freight charges.
The root of all this lies in the fact that safety is the unwavering lifeline of air transport. This article will delve into why air freight for powder is so special and provide a detailed interpretation of the authoritative regulations of the International Air Transport Association (IATA).
Chapter 1: Root Cause Analysis – Why is Powder a “Sensitive Word” in Air Transport?
Powder is considered a high-risk cargo in air transport primarily due to its unique physical characteristics, which can pose two major fatal threats in the aviation environment:
- The “Invisible Bomb” of Dust Explosions
Large Surface Area: After powder is broken into tiny particles, its total surface area increases dramatically, resulting in ample contact with air.
- Suspended Powder Clouds Explode Upon Ignition: During flight, aircraft vibrations and handling operations can lead to powder leaks. When leaked powder forms a dust cloud of a certain concentration in the cargo hold air, it can instantly trigger a violent dust explosion upon encountering a tiny ignition source (such as an electrical spark or electrostatic discharge).
Extremely Destructive: The initial explosion can dislodge accumulated powder inside the cargo hold, triggering secondary and even more violent chain explosions, powerful enough to destroy the aircraft structure.
- Silent Erosion of Aircraft Systems
Penetration and Conductivity: Extremely fine powders (such as certain metal powders and chemical powders) have extremely strong penetrating power. They can easily penetrate cargo hold linings and enter the aircraft’s critical electronic equipment, wiring ducts, and ventilation systems.
Causing System Failures: Powder accumulation can lead to short circuits, overheating, and malfunctions in equipment; the risk is even higher if the powder is conductive. This poses a serious and irreversible threat to flight safety.
Based on these non-negotiable safety considerations, IATA has established extremely strict and detailed regulations for powder cargoes in the Dangerous Goods Regulations (DGR).
Chapter Two: Core of the Regulations—Detailed Explanation of IATA DGR’s Classification and Regulations for Powders
IATA DGR classifies powder cargoes into two main categories, with drastically different procedures.
Class A: Powders explicitly listed as dangerous goods
These powders will be clearly identified as dangerous goods on the Certificate of Cargo Transport Conditions, and assigned a UN number and hazard class. Common examples include:
Flammable solids (Class 4.1): such as sulfur, certain activated carbons.
Self-reactive substances (Class 4.1): such as certain foaming powders.
Oxidizing substances (Class 5.1): such as potassium permanganate, sodium persulfate.
Toxic substances (Class 6.1): such as certain pesticide powders.
Corrosive substances (Class 8): such as sodium hydroxide powder.
Transportation Requirements:
Passenger aircraft transport is strictly prohibited: Only cargo aircraft are permitted.
UN-certified packaging: Must use UN-certified combination packaging corresponding to the correct Packing Group (PG).
Full declaration: Must be formally declared as dangerous goods, submitting a Dangerous Goods Declaration Form.
High costs: Dangerous goods handling fees and higher dangerous goods freight rates apply.
Category B: Air-restricted “General Cargo” Powders – Crucial!
This is the area most prone to confusion and risk. Even if your powder is identified as non-restricted general cargo, it does not mean it can be transported freely by air. IATA has specific “cargo-only” regulations for this type of powder.
- Why are “General Cargo” Powders Restricted?
As mentioned earlier, even if the powder itself is not chemically hazardous, its physical properties (easily leakable, fine particles) can still pose a threat to the aircraft’s flight systems. Therefore, IATA adopts a “cautionary principle.”
- Key Identification: These types of goods will typically be described on the Air Cargo Inspection Certificate as follows:
“This cargo is non-restricted and is for cargo transport only.”
The corresponding transport designation is: “Chemicals, n.o.s.” or “Environmentally hazardous substance, solid, n.o.s.”, with a specified UN number (usually UN3077 or UN3082).
- Core Requirements:
Cargo Aircraft Only: This is a mandatory requirement. It cannot be carried on any passenger flights.
Special Packing (Packing Instruction 955): IATA DGR specific packaging instruction PI 955 for this type of cargo must be followed. Core requirements include:
Leak-proof Design: The inner packaging must completely prevent powder leakage (e.g., using heat-sealed plastic bags).
Secondary Enclosure: The inner packaging must be placed within a sufficiently robust intermediate or outer packaging that completely contains the contents.
Adsorption and Fixation: If the inner packaging is fragile (e.g., glass bottles), sufficient absorbent and padding materials must be used between the inner and outer packaging to ensure it does not break during transport and can absorb all liquid (if applicable).
Non-Dangerous Goods Declaration, but Requires Special Labeling: Although not declared as dangerous goods, the “Handling Information” section of the air waybill (AWB) must clearly state: “Cargo Aircraft Only” or “CAO”.
Chapter 3: Practical Process – Your Powder Air Transport Compliance Roadmap
Absolute Taboo: Concealment and Misdeclaration
Any attempt to conceal powder (especially powder “cargo only”) as ordinary cargo is considered a serious violation in the aviation industry. Once discovered, it will result in hefty fines, blacklisting, and even criminal liability.
Summary
The high barriers to entry in powder air transport are safety barriers learned through painful lessons in the aviation industry. Its core lies in:
Respect for the Rules: Fully recognizing the unique threat that powder poses to aviation safety.
Reliance on Certification: We absolutely adhere to the “Cargo Transport Conditions Certificate” issued by an authoritative institution, which includes air transport conclusions, as our sole guiding principle.
Precise Operation: We strictly distinguish between “dangerous goods” and “general cargo limited to freighters,” and comply with the corresponding packaging and declaration regulations in IATA DGR for each.
Only by prioritizing compliance over cost and convenience can your powder cargo safely and smoothly reach the world.