Class 4 Divisions and Controls
Flammable and self-reactive solids, spontaneous combustion and substances dangerous when wet.
How to prepare for UK ADR driver training
Confirm the qualification route first, master Core, then combine the correct class and Packages, Bulk or Tanks content with approved practical training.
Core concepts
Concept 1
Division 4.1 covers flammable solids and related self-reactive or desensitized explosive hazards.
Exam cue: Identify the division before choosing water, ventilation or containment.
Concept 2
Division 4.2 covers substances liable to spontaneous combustion; Division 4.3 can release flammable gas with water.
Exam cue: Look for heating, wetting, damaged containment and incompatible contamination.
Concept 3
Temperature control, dryness, segregation and protection from damage are selected by classification.
Exam cue: Use SADT or SAPT controls where the transport entry requires them.
Risk pitfalls and guardrails
Applying water to a Division 4.3 incident automatically.
Guardrail: Do not treat an exemption, valid card, approved package or posted speed as permission to ignore the actual conditions and remaining duties.
Ignoring slow self-heating because there is no flame.
Guardrail: Do not treat an exemption, valid card, approved package or posted speed as permission to ignore the actual conditions and remaining duties.
Breaking temperature control or mixing with incompatible materials.
Guardrail: Do not treat an exemption, valid card, approved package or posted speed as permission to ignore the actual conditions and remaining duties.
Memory anchors
4.1 Burns or Reacts
Flammable solids and certain self-reactive or desensitized goods sit in 4.1.
4.2 Self-Heats
Spontaneous-combustion risk can develop without an external flame.
4.3 Water Releases Gas
Water contact can generate dangerous flammable gas.
Division Before Water
Identify the exact Class 4 division before selecting an extinguishing response.
Temperature Is a Limit
Where required, maintain control temperatures and recognise emergency limits.
Keep Incompatibles Apart
Prevent contamination, friction and reactions through correct segregation.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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