NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Borates, tetra, sodium salts (Pentahydrate)

CAS
12179-04-3

Na2B4O7 • 5H2O

RTECS
VZ2540000
Synonyms & Trade Names

Borax pentahydrate, Sodium borate pentahydrate, Sodium tetraborate pentahydrate
DOT ID & Guide

Exposure
Limits

NIOSH REL: TWA 1 mg/m3
OSHA PEL: none
IDLH
N.D. See: IDLH INDEX
Conversion
Physical Description
Colorless or white, odorless crystals or free-flowing powder. [herbicide] [Note: Begins to lose water of hydration at 252°F.]
MW: 291.4
BP: ?
MLT: 392°F
Sol: 3%
VP: 0 mmHg (approx)
IP: NA

Sp.Gr: 1.82
Fl.P: NA
UEL: NA
LEL: NA

Noncombustible Solid
Incompatibilities & Reactivities

None reported [However, see the reactivities & incompatibilities reported for the related substance Borax decahydrate above.]
Measurement Methods
NIOSH 0500; OSHA ID125G
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
Skin: No recommendation
Eyes: No recommendation
Wash skin: Daily
Remove: No recommendation
Change: Daily

First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Soap wash
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations
Not available.
Important additional information about respirator selection
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
Irritation eyes, skin, upper respiratory system; dermatitis; epistaxis (nosebleed); cough, dyspnea (breathing difficulty)
Target Organs
Eyes, skin, respiratory system
See also: INTRODUCTION