UN3520: Chlorine, adsorbed
UN3520 appears 1 time in the Hazardous Materials Table (49 CFR §172.101). Hazard class 2.3.
All §172.101 entries for UN3520
| Proper shipping name | Class | PG | Labels |
|---|---|---|---|
| Chlorine, adsorbed | 2.3 | — | 2.3, 5.1, 8 |
Open any entry for packaging sections, special provisions, air limits and vessel stowage.
What it means
Label codes (column 6): 2.3, 5.1, 8 → Poison gas label + subsidiary Oxidizer, Corrosive labels.
UN numbers are recognized for international and domestic transport.
Example basic description
Proper shipping name shown without the table's italic descriptive text. Order per §172.202: ID number, proper shipping name, hazard class, packing group. Example only — add technical names, “RQ”, quantities and other elements your shipment requires.
What to check next
- Match the name. Compare your SDS Section 14 to the proper shipping names above and pick the row with your packing group.
- Read the special provisions on the entry page (§172.102) — they can add limits or exceptions.
- Check packaging — the entry page lists the Part 173 sections for exceptions, non-bulk and bulk.
- Labels & placards. Placarding depends on class and quantity — see Table 1 vs Table 2.
- Emergency response. Find the response guide for UN3520 in the current PHMSA Emergency Response Guidebook.
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Common questions about UN3520
What is UN3520?
UN3520 is the identification number for Chlorine, adsorbed in the DOT Hazardous Materials Table (49 CFR §172.101).
What hazard class is UN3520?
UN3520 is listed under hazard class 2.3 (poisonous (toxic) gas).
What packing group is UN3520?
Packing group for UN3520: not assigned. Where several rows exist, the packing group that fits your material decides which row applies.