☣️ UN 2793 • CLASS 4

UN 2793 — Ferrous metal borings, shavings, turnings or cuttings

Placard: Spontaneously Combustible. ERG Guide 170. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.

🚒☣️
⚠️ Verification required: Broad or variable material category; verify exact product, SDS and shipping papers.
⚠️ This page is a quick-reference aid. For real incidents: stage upwind, isolate, deny entry, request Hazmat early, and consult the current ERG + SOP/SOG.

Ferrous metal borings, shavings, turnings or cuttings are reactive metal scrap forms that can self-heat, ignite or release hydrogen depending on contamination and moisture.

Hazard overview: Ferrous borings, shavings, turnings or cuttings can self-heat when contaminated with oil or moisture. Fine metal particles may ignite from friction, sparks, heat or static discharge. Contact with water may generate heat and flammable hydrogen under some conditions.

Response guidance: Isolate the pile or container, remove ignition sources and avoid disturbing hot material. Use dry sand or Class D-compatible media when water reactivity is suspected; monitor for re-ignition.

Firefighter training notes: Train responders to identify the UN number, product name, placard, container type and exposure route before committing personnel to the hot zone.

Regulatory context: Use the proper DOT shipping description, ERG guide, SDS and site-specific response plan; do not substitute this summary for regulatory compliance.

Storage & handling: Keep dry, cool and separated from oxidizers, acids, ignition sources and incompatible scrap; prevent oil-soaked piles from self-heating.

Advertisement

UN 2793 Quick Details

UN 2793
Product name: Ferrous metal borings, shavings, turnings or cuttings
DOT Class: 4
Placard type: Spontaneously Combustible
ERG Guide: 170 (check current ERG)
Initial isolation: Use ERG 170; isolate hot or self-heating material and monitor for re-ignition after apparent extinguishment.

Common Hazards of UN 2793

  • Ferrous borings, shavings, turnings or cuttings can self-heat when contaminated with oil or moisture.
  • Fine metal particles may ignite from friction, sparks, heat or static discharge.
  • Contact with water may generate heat and flammable hydrogen under some conditions.
  • Piles or drums can retain heat and re-ignite after apparent extinguishment.
  • Material transported in flammable liquid can add vapor and flashback hazards.
  • Fire may produce dense smoke and metal oxide fumes.
  • Runoff or water application may spread burning or reactive fines.
  • Container drums may rupture when heated.

Chemical Identity & Physical Properties

Gray to dark gray metallic solid particles, shavings, or filings. Odorless. Fine particles may be pyrophoric when dry or in presence of oil/cutting fluids.

Also known asiron boringssteel shavingsferrous turningsmetal cuttingsiron filingssteel borings
AppearanceGray to dark gray metallic solid particles, shavings, or filings. Odorless. Fine particles may be pyrophoric when dry or in presence of oil/cutting fluids.
Flash PointNot applicable (solid metal particles)
Boiling PointNot applicable (solid metal, decomposes/oxidizes before melting point)
Vapor DensityNot applicable (solid)
Water ReactivityMay react with water or moisture in some conditions, producing heat and hydrogen; keep dry unless specialist guidance approves water.
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.

Fireground Response Guidance — UN 2793

Extinguishing Media

Use dry sand or Class D-compatible media for metal fire behavior; avoid foam or water on reactive material.

PPE Requirements

⚠️ Fire-resistant clothing and SCBA for fire; avoid dust inhalation, hot particles and sharp metal scrap.

Level C minimum for handling. SCBA and structural firefighters' protective clothing for fires. Avoid friction or impact that may cause ignition.

Isolation & Evacuation

Use ERG 170; isolate hot or self-heating material and monitor for re-ignition after apparent extinguishment.
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 170).

First Actions for a UN 2793 Incident

  • Call 911 and the emergency response number shown on the shipping papers.
  • Keep unauthorized personnel away and establish an initial isolation perimeter.
  • Stay upwind, uphill and upstream; avoid low areas where vapors or runoff may collect.
  • Avoid breathing vapors, dust, mist or smoke and prevent skin and eye contact.
  • Do not touch damaged packages, leaking containers or spilled material without appropriate PPE.
  • Eliminate ignition sources; stop traffic, engines, smoking and open flames if it can be done safely.
  • Ventilate confined spaces only when responders are trained, equipped and monitoring conditions.
  • Use ERG, SDS, shipping papers and air monitoring to set final isolation, evacuation and decon actions.
Advertisement

📋 Copy & Share Field Card

UN 2793 — Ferrous metal borings, shavings, turning
HAZMAT RADIO NOTE — UN 2793 Product: Ferrous metal borings, shavings, turnings or cuttings Class 4 / Spontaneously Combustible / ERG 170 PPE: Fire-resistant clothing and SCBA for fire; avoid dust inhalation, hot particles and sharp metal scrap. ISOLATION: Use ERG 170; isolate hot or self-heating material and monitor for re-ignition after apparent extinguishment. ACTION: Stage upwind · Isolate · Deny entry · Request HazmatRADIO

Use for: Quick radio or face-to-face size-up. Short, structured, field-ready.

SMS WhatsApp
=== IC HAZMAT BRIEFING === UN 2793 — Ferrous metal borings, shavings, turnings or cuttings Class: 4 | Placard: Spontaneously Combustible | ERG Guide: 170 Appearance: Gray to dark gray metallic solid particles, shavings, or filings. Odorless. Fine particles may be pyrophoric when dry or in presence of oil/cutting fluids. Water Reactivity: May react with water or moisture in some conditions, producing heat and hydrogen; keep dry unless specialist guidance approves water. Extinguishing: Use dry sand or Class D-compatible media for metal fire behavior; avoid foam or water on reactive material. PPE: Fire-resistant clothing and SCBA for fire; avoid dust inhalation, hot particles and sharp metal scrap. Isolation: Use ERG 170; isolate hot or self-heating material and monitor for re-ignition after apparent extinguishment. — Key Hazards — • Ferrous borings, shavings, turnings or cuttings can self-heat when contaminated with oil or moisture. • Fine metal particles may ignite from friction, sparks, heat or static discharge. • Contact with water may generate heat and flammable hydrogen under some conditions. — First Actions — • Call 911 and the emergency response number shown on the shipping papers. • Keep unauthorized personnel away and establish an initial isolation perimeter. • Stay upwind, uphill and upstream; avoid low areas where vapors or runoff may collect. • Avoid breathing vapors, dust, mist or smoke and prevent skin and eye contact. SOURCE: allfirefighter.com/hazmat/un/ferrous-metal-borings-shavings-un-2793 | Always use current ERG + SOP/SOGIC BRIEFING

Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.

SMS (short)
UN2793 Ferrous metal borings, shavings, turnings or cuttings Cls4 ERG170 | allfirefighter.com/hazmat/un/ferrous-metal-borings-shavings-un-2793SMS / 160 CHAR

Use for: Quick text to command or incoming units. Fits in a single SMS.

⚠️ Quick-reference only. Always use current ERG + SOP/SOG for incident-specific actions. Page: https://allfirefighter.com/hazmat/un/ferrous-metal-borings-shavings-un-2793

Related UN Numbers in Class 4

Discovery block for training / quick reference. Always consult the current ERG + your SOP/SOG for operations.
Advertisement

Frequently Asked Questions about UN 2793

UN 2793 covers Ferrous metal borings, shavings, turnings or cuttings. Use the shipping papers and SDS to confirm the exact product before choosing tactics.

Yes. Keep ignition sources away because vapors can ignite and flash back from low or confined areas.

Some loads may react with water or moisture and release heat or hydrogen; verify SDS and avoid direct water if reaction is suspected.

Use dry sand or Class D-compatible extinguishing media when metal fire behavior is present; cool exposures from a safe distance.

Use SCBA and chemical-resistant protective clothing. Level A or B may be needed when vapors, splash risk or product identity is uncertain.

This entry can cover different formulations, active ingredients and solvents, so response details may change by product.
Sources (high level): DOT/PHMSA marking & class concepts + ERG usage principles. This page does not reproduce ERG guide text—always consult the current ERG for incident-specific protective actions.