UN 3483 — Motor fuel anti-knock mixture, flammable
Placard: Toxic. ERG Guide 131. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3483 At a Glance
UN 3483 (Motor fuel anti-knock mixture, flammable) is listed as DOT Class 6 Toxic and is assigned to ERG Guide 131. Use this page to review placard data, common hazards, PPE notes, isolation context, first actions, and related UN numbers.
UN 3483 covers flammable motor fuel anti-knock mixtures, historically associated with highly toxic lead-containing fuel additives.
Hazard overview: The material is both toxic and flammable. Vapors may form explosive mixtures, and liquid contact can allow dangerous absorption through skin.
Response guidance: Isolate the area, eliminate ignition sources, prevent runoff, and use alcohol-resistant foam, dry chemical, or CO2. Use water spray for cooling only.
UN 3483 Quick Details
Common Hazards of UN 3483
- TOXIC; may be fatal if inhaled, ingested or absorbed through skin.
- Inhalation or contact with some of these materials will irritate or burn skin and eyes.
- Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears).
- Fire will produce irritating, corrosive and/or toxic gases.
- Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas.
- Runoff from fire control or dilution water may cause environmental contamination.
- HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
- Vapors may form explosive mixtures with air.
Chemical Identity & Physical Properties
It is a clear to amber liquid with a characteristic sweet or aromatic odor.
| Also known as | Tetraethyl lead anti-knock compoundTEL anti-knock mixtureGasoline additive anti-knockLead alkyl anti-knock fluid |
| Appearance | Clear to amber liquid with a characteristic sweet or aromatic odor. Highly toxic organo-lead compound mixture used as gasoline additive. |
| Flash Point | -18C (0F) typical |
| Boiling Point | 110-200C (230-392F) range depending on formulation |
| Vapor Density | 7-8 (much heavier than air) |
| Water Reactivity | No significant reaction with water, but insoluble and will float forming toxic vapors |
Fireground Response Guidance — UN 3483
Extinguishing Media
PPE Requirements
Level A or B with SCBA and a chemical-resistant suit is recommended. Avoid all skin contact because severe systemic toxicity is possible.
Isolation & Evacuation
First Actions for a UN 3483 Incident
- CALL 911. Then call the emergency response number on the shipping paper, if available.
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Ventilate closed spaces before entering, but only if properly trained and equipped.
- Isolate spill or leak area for at least 50 meters (150 feet) in all directions.
- For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.
- For non-highlighted materials, increase the downwind precautionary distance as conditions require.
📋 Copy & Share Field Card
UN 3483 — Motor fuel anti-knock mixture, flammableUse for: Quick radio or face-to-face size-up. Short, structured, field-ready.
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
Use for: Quick text to command or incoming units. Fits in a single SMS.