☣️ UN 2437 • CLASS 8
Methylphenyldichlorosilane
Placard: Corrosive. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
🚒☣️
⚠️ 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.
Advertisement
Quick details
UN 2437
Class: 8
Placard type: Corrosive
ERG: Guide 156 (check current ERG)
Isolation: ERG 156: Isolate spill area 25-50m in all directions. If tank/rail car involved in fire, isolate 800m in all directions and consider evacuation.
Chemical & Response Details
| Also known as | MethylphenyldichlorosilaneDichloro(methyl)phenylsilanePhenylmethyldichlorosilaneMethylphenylsilicon dichloride |
| CAS Number | 149-74-6 |
| Appearance | Colorless to pale yellow liquid with a pungent, irritating odor. Reacts violently with water, producing corrosive fumes. |
| Flash Point | 71°C (160°F) |
| Boiling Point | 205°C (401°F) |
| Vapor Density | 6.6 (heavier than air) |
| Water Reactivity | Reacts violently with water, releasing hydrochloric acid (HCl) fumes and heat. Do not use water directly on material. |
| Extinguishing | Dry chemical, CO2, or dry sand. Do not use water or aqueous foam directly on material. |
| PPE | ⚠️ Level B minimum with SCBA required. Full chemical-resistant suit for contact hazard. Avoid all skin and eye contact. |
| Isolation | ERG 156: Isolate spill area 25-50m in all directions. If tank/rail car involved in fire, isolate 800m in all directions and consider evacuation. |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
- Combustible material: may burn but does not ignite readily.
- Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff.
- When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion
- Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas
- Vapors may travel to source of ignition and flash back.
- Corrosives in contact with metals may evolve flammable hydrogen gas.
- Containers may explode when heated or if contaminated with water.
- TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance
First actions (field-minded)
- CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
- 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 in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.
- For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind
Advertisement
📋 Copy & Share
UN 2437 — Methylphenyldichlorosilane HAZMAT RADIO NOTE — UN 2437
Product: Methylphenyldichlorosilane
Class 8 / Corrosive / ERG 156
PPE: Level B minimum with SCBA required. Full chemical-resistant suit for contact hazard. Avoid all skin and eye contact.
ISOLATION: ERG 156: Isolate spill area 25-50m in all directions. If tank/rail car involved in fire, isolate 800m in all directions and consider evacuation.
ACTION: Stage upwind · Isolate · Deny entry · Request HazmatRADIO
Use for: Quick radio or face-to-face size-up. Short, structured, field-ready.
=== IC HAZMAT BRIEFING ===
UN 2437 — Methylphenyldichlorosilane
Class: 8 | Placard: Corrosive | ERG Guide: 156
Appearance: Colorless to pale yellow liquid with a pungent, irritating odor. Reacts violently with water, producing corrosive fumes.
Water Reactivity: Reacts violently with water, releasing hydrochloric acid (HCl) fumes and heat. Do not use water directly on material.
Extinguishing: Dry chemical, CO2, or dry sand. Do not use water or aqueous foam directly on material.
PPE: Level B minimum with SCBA required. Full chemical-resistant suit for contact hazard. Avoid all skin and eye contact.
Isolation: ERG 156: Isolate spill area 25-50m in all directions. If tank/rail car involved in fire, isolate 800m in all directions and consider evacuation.
— Key Hazards —
• Combustible material: may burn but does not ignite readily.
• Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff.
• When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion
— First Actions —
• CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
• Keep unauthorized personnel away.
• Stay upwind, uphill and/or upstream.
• Ventilate closed spaces before entering, but only if properly trained and equipped.
SOURCE: allfirefighter.com/hazmat/un/2437 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN2437 Methylphenyldichlorosilane Cls8 ERG156 | allfirefighter.com/hazmat/un/2437SMS / 160 CHAR
Use for: Quick text to command or incoming units. Fits in a single SMS. Includes link to full page.
⚠️ Quick-reference only. Always use current ERG + SOP/SOG for incident-specific actions. Page: https://allfirefighter.com/hazmat/un/2437
Advertisement
FAQ
Combustible material: may burn but does not ignite readily. Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas Vapors may travel to source of ignition and flash back. Corrosives in contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water. TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance
CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper Keep unauthorized personnel away. Stay upwind, uphill and/or upstream.
Level B minimum with SCBA required. Full chemical-resistant suit for contact hazard. Avoid all skin and eye contact.
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 156 and your department SOP/SOG for incident-specific protective actions.
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.