UN 1742 — Boron trifluoride acetic acid complex, liquid
Placard: Corrosive. ERG Guide 157. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Boron trifluoride acetic acid complex, also known as Boron trifluoride acetate or Trifluoroborane acetic acid complex, is a clear to pale yellow liquid with a pungent, acrid odor. It is classified as a DOT Class 8 substance and is used in various industrial applications. First responders may encounter boron trifluoride acetic acid complex during transportation accidents or industrial fires. The scale of production and transport of boron trifluoride acetic acid complex is significant, making it a potential hazard for emergency responders. The substance is toxic and corrosive, and its reaction with water or moist air may release toxic, corrosive, or flammable gases. It is essential for first responders to be aware of the hazards associated with boron trifluoride acetic acid complex and take necessary precautions during emergency response situations.
Hazard overview: Boron trifluoride acetic acid complex is a toxic and corrosive substance that can cause severe health effects, including respiratory problems and skin irritation. The substance reacts with water or moist air, releasing toxic, corrosive, or flammable gases. When heated, the substance may generate much heat, increasing the concentration of fumes in the air. The flash point of boron trifluoride acetic acid complex is 40°C (104°F), and the boiling point is approximately 120-125°C (248-257°F) with decomposition. The vapor density of the substance is heavier than air, and the substance can release toxic and corrosive gases in the event of a fire. The worst-case scenario for first responders is a large-scale fire or explosion, and the substance's reactivity with water can exacerbate the situation.
Response guidance: In the event of a boron trifluoride acetic acid complex spill or leak, first responders should isolate the area 50m in all directions immediately and evacuate 300m downwind if the material is on fire or releasing vapors. The correct suppression agent, such as dry chemical, CO2, or dry sand, should be used. Water-based agents should be avoided due to the substance's violent reaction with water. Decontamination procedures should be followed, and CHEMTREC should be contacted for assistance. It is essential to note that boron trifluoride acetic acid complex reacts with water, releasing toxic and corrosive hydrogen fluoride and acetic acid fumes, and generates heat. First responders should be aware of this reactivity and take necessary precautions to avoid exacerbating the situation.
Firefighter training notes: First responders should receive training on the hazards associated with boron trifluoride acetic acid complex, including its toxic and corrosive properties. They should be aware of the substance's reactivity with water and the potential for violent reactions. A known tactical error for this chemical class is the use of water-based agents for suppression, which can exacerbate the situation. ICS position needs and mutual aid criteria should be established to ensure a coordinated response. First responders should be competent in the use of PPE and decontamination procedures to ensure a safe and effective response.
Regulatory context: Boron trifluoride acetic acid complex is classified as a DOT Class 8 substance, and its transportation is regulated by the DOT. The OSHA PEL for boron trifluoride acetic acid complex is not well-established, but the substance is subject to various regulations due to its toxic and corrosive properties.
Storage & handling: Boron trifluoride acetic acid complex should be stored in a cool, dry, and well-ventilated area, away from incompatible materials such as water and moisture. The temperature limit for storage is 40°C (104°F), and the substance should be kept away from heat sources. The top three incompatible materials for boron trifluoride acetic acid complex are water, moisture, and heat sources. Ventilation standards should be followed to prevent the accumulation of boron trifluoride acetic acid complex vapors.
UN 1742 Quick Details
Common Hazards of UN 1742
- TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance
- Reaction with water or moist air may release toxic, corrosive or flammable gases.
- Reaction with water may generate much heat that will increase the concentration of fumes in the air.
- Fire will produce irritating, corrosive and/or toxic gases.
- Runoff from fire control or dilution water may be corrosive and/or toxic and cause environmental
- Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive
- UN1802, UN2032, UN3084, UN3093, UN1796 (above 50%), UN1826 (above 50%), and UN2031 (above
- Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.).
Chemical Identity & Physical Properties
Boron trifluoride acetic acid complex is a clear to pale yellow liquid with a pungent, acrid odor. It has a flash point of 40°C (104°F) and a boiling point of approximately 120-125°C (248-257°F) with decomposition. The vapor density of the substance is heavier than air, and the substance fumes in moist air due to its reaction with atmospheric moisture.
| Also known as | Boron trifluoride acetateBF3 acetic acid complexTrifluoroborane acetic acid complexBoron fluoride acetic acid adduct |
| CAS Number | 373-61-5 |
| Appearance | Clear to pale yellow liquid with a pungent, acrid odor. Fuming in moist air due to reaction with atmospheric moisture. |
| Flash Point | 40C (104F) |
| Boiling Point | Approximately 120-125C (248-257F) with decomposition |
| Vapor Density | Heavier than air (vapors sink and accumulate in low areas) |
| Water Reactivity | Reacts with water releasing toxic and corrosive hydrogen fluoride and acetic acid fumes; generates heat |
Fireground Response Guidance — UN 1742
Extinguishing Media
PPE Requirements
The minimum PPE level required for boron trifluoride acetic acid complex response is Level B, which includes an SCBA and a full chemical-resistant suit. Rubber or neoprene gloves, a face shield, and eye protection are also mandatory. The rationale for each item is to prevent skin contact and inhalation of boron trifluoride acetic acid complex vapors, which can cause severe health effects.
Isolation & Evacuation
First Actions for a UN 1742 Incident
- 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
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