What class hazmat does explosive 1.5 vs explosive 1.6 show up visually practice site test…?
Both are Class 1 explosives on the same orange placard, so the division number carries the meaning. Division 1.5 is very insensitive substances that still have a mass explosion hazard. Division 1.6 is extremely insensitive articles with no mass explosion hazard, the least hazardous division in Class 1.
Same orange diamond, different division
All Class 1 explosives use an orange placard, so the number after the dot is what changes the meaning. Reading only the color and the 1 is not enough; the division tells you how the material behaves, from a full mass detonation down to almost inert articles.
Where 1.5 and 1.6 sit
The full division scale, low number to high:
| Division | Hazard |
|---|---|
| 1.1 | Mass explosion hazard (most dangerous) |
| 1.2 | Projection hazard |
| 1.3 | Fire with minor blast or projection |
| 1.4 | Minor explosion hazard |
| 1.5 | Very insensitive, but with a mass explosion hazard |
| 1.6 | Extremely insensitive, no mass explosion hazard |
1.5 is very insensitive yet can still mass-explode; 1.6 is the least hazardous. Confirm details in your official manual.
The compatibility group letter
Class 1 placards also carry a letter, the compatibility group, which controls which explosives may be loaded and transported together. It is part of why explosives are placarded and handled so carefully. For the test, the key point is that 1.5 still carries a mass explosion hazard while 1.6 does not. Verify the specifics in the official regulations.
Frequently asked questions
- What is the difference between Division 1.5 and 1.6?
- Division 1.5 is very insensitive substances that still have a mass explosion hazard; Division 1.6 is extremely insensitive articles with no mass explosion hazard, the least dangerous division. Both are orange Class 1. Confirm in your official manual.
- Which explosive division is the least dangerous?
- Division 1.6, extremely insensitive articles with no mass explosion hazard. Division 1.1, with a mass explosion hazard, is the most dangerous.
- What does the letter on an explosives placard mean?
- It is the compatibility group, which governs which explosives can be transported together. Verify the rules in the official regulations.