# NIOSH Pocket Guide to Chemical Hazards
Hydrogen bromide | CAS 10035-10-6
HBr | RTECS MW3850000
Synonyms & Trade Names Anhydrous hydrogen bromide; Aqueous hydrogen bromide (i.e., Hydrobromic acid) | DOT ID & Guide 1048 125 (anhydrous) 1788 154 (solution)
Exposure Limits | NIOSH REL: C 3 ppm (10 mg/m3)
OSHA PEL†: TWA 3 ppm (10 mg/m3)
IDLH 30 ppm | Conversion 1 ppm = 3.31 mg/m3
Physical Description Colorless gas with a sharp, irritating odor. [Note: Shipped as a liquefied compressed gas. Often used in an aqueous solution.]
MW: 80.9 | BP: -88°F | FRZ: -124°F | Sol: 49%
VP: 20 atm | IP: 11.62 eV | RGasD: 2.81 |
Fl.P: NA | UEL: NA | LEL: NA |
Nonflammable Gas
Incompatibilities & Reactivities Strong oxidizers, strong caustics, moisture, copper, brass, zinc [Note: Hydrobromic acid is highly corrosive to most metals.]
Measurement Methods NIOSH 7903; OSHA ID165SG
Personal Protection & Sanitation Skin: Prevent skin contact (solution)/Frostbite Eyes: Prevent eye contact (solution)/Frostbite Wash skin: When contaminated (solution) Remove: When wet or contaminated (solution) Change: No recommendation Provide: Eyewash (liquid), Quick drench (solution), Frostbite | First Aid (See procedures) Eye: Irrigate immediately (solution)/Frostbite Skin: Water flush immediately (solution)/Frostbite Breathing: Respiratory support Swallow: Medical attention immediately (solution)
Respirator Recommendations NIOSH/OSHA Up to 30 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode£/(APF = 25) Any powered, air-purifying respirator with acid gas cartridge(s)£/(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted acid gas canister/(APF = 50) Any self-contained breathing apparatus with a full facepiece/(APF = 50) Any supplied-air respirator with a full facepiece Emergency or planned entry into unknown concentrations or IDLH conditions: (APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode/(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus Escape: (APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted acid gas canister/Any appropriate escape-type, self-contained breathing apparatus
Exposure Routes inhalation, ingestion (solution), skin and/or eye contact
Symptoms Irritation eyes, skin, nose, throat; solution: eye, skin burns; liquid: frostbite
Target Organs Eyes, skin, respiratory system
See also: INTRODUCTION