☣️ UN 1748 • CLASS 5
Calcium hypochlorite mixture, dry, with more than 39% available chlorine (8.8% available oxygen)
Placard: Oxidizer. 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 1748
Class: 5
Placard type: Oxidizer
ERG: Guide 140 (check current ERG)
Isolation: ERG 140: Initial isolation 50m in all directions; protective action distance 100m downwind for small spills, 500m downwind for large spills; if tank/rail car involved in fire, isolate 800m in all directions
Chemical & Response Details
| Also known as | Calcium oxychlorideChlorinated limeHTHLosantinPittchlorBleaching powder |
| CAS Number | 7778-54-3 |
| Appearance | White granular solid or powder with a strong chlorine-like odor. May appear slightly yellow or gray depending on purity. |
| Flash Point | Not applicable (oxidizing solid, non-flammable but supports combustion) |
| Boiling Point | Not applicable (decomposes at approximately 180C/356F) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Reacts with water releasing oxygen and heat; may produce chlorine gas when wet or in acidic conditions |
| Extinguishing | Do not use water or foam; use dry chemical, sand, or soda ash for small fires; flood area with large volumes of water for large fires from a distance |
| PPE | ⚠️ Level B minimum with full-face SCBA required; chemical-resistant suit for spill cleanup; avoid all contact as material is corrosive and oxidizing |
| Isolation | ERG 140: Initial isolation 50m in all directions; protective action distance 100m downwind for small spills, 500m downwind for large spills; if tank/rail car involved in fire, isolate 800m in all directions |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
- These substances will accelerate burning when involved in a fire.
- Some may decompose explosively when heated or involved in a fire.
- May explode from heat or contamination.
- Some will react explosively with hydrocarbons (fuels).
- May ignite combustibles (wood, paper, oil, clothing, etc.).
- Containers may explode when heated.
- Runoff may create fire or explosion hazard.
- Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or
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
- Consider initial downwind evacuation for at least 100 meters (330 feet).
Advertisement
📋 Copy & Share
UN 1748 — Calcium hypochlorite mixture, dry, with HAZMAT RADIO NOTE — UN 1748
Product: Calcium hypochlorite mixture, dry, with more than 39% available chlorine (8.8% available oxygen)
Class 5 / Oxidizer / ERG 140
PPE: Level B minimum with full-face SCBA required; chemical-resistant suit for spill cleanup; avoid all contact as material is corrosive and oxidizing
ISOLATION: ERG 140: Initial isolation 50m in all directions; protective action distance 100m downwind for small spills, 500m downwind for large spills; if tank/rail car involved in fire, isolate 800m in all directions
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 1748 — Calcium hypochlorite mixture, dry, with more than 39% available chlorine (8.8% available oxygen)
Class: 5 | Placard: Oxidizer | ERG Guide: 140
Appearance: White granular solid or powder with a strong chlorine-like odor. May appear slightly yellow or gray depending on purity.
Water Reactivity: Reacts with water releasing oxygen and heat; may produce chlorine gas when wet or in acidic conditions
Extinguishing: Do not use water or foam; use dry chemical, sand, or soda ash for small fires; flood area with large volumes of water for large fires from a distance
PPE: Level B minimum with full-face SCBA required; chemical-resistant suit for spill cleanup; avoid all contact as material is corrosive and oxidizing
Isolation: ERG 140: Initial isolation 50m in all directions; protective action distance 100m downwind for small spills, 500m downwind for large spills; if tank/rail car involved in fire, isolate 800m in all directions
— Key Hazards —
• These substances will accelerate burning when involved in a fire.
• Some may decompose explosively when heated or involved in a fire.
• May explode from heat or contamination.
— 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/1748 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN1748 Calcium hypochlorite mixture, dry, with more than 39% available chlorine (8.8% available oxygen) Cls5 ERG140 | allfirefighter.com/hazmat/un/1748SMS / 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/1748
Advertisement
FAQ
These substances will accelerate burning when involved in a fire. Some may decompose explosively when heated or involved in a fire. May explode from heat or contamination. Some will react explosively with hydrocarbons (fuels). May ignite combustibles (wood, paper, oil, clothing, etc.). Containers may explode when heated. Runoff may create fire or explosion hazard. Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or
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 full-face SCBA required; chemical-resistant suit for spill cleanup; avoid all contact as material is corrosive and oxidizing
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 140 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.