SODIUM TETRABORATE PENTAHYDRATE

Chemical Identification
CAS # 12179-04-3
Formula

Na₂B₄O₇ = ₅H₂O

Synonyms

borax pentahydrate; sodium borate pentahydrate; sodium tetraborate pentahydrate

Physical Properties
Physical description Colorless or white, odorless crystals or free-flowing powder.
Boiling point Molecular weight 291.4
Freezing point/melting point 392°F Vapor pressure 0 mmHg (approx)
Flash point Vapor density
Specific gravity 1.82 Ionization potential
Lower explosive limit (LEL) Upper explosive limit (UEL)
NFPA health rating NFPA fire rating
NFPA reactivity rating NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs
Monitoring Methods Used by OSHA
Analyte code (IMIS no.) 0376
Sampling group
Sampler/Sampling media Mixed cellulose ester filter (MCEF) 0.8 micron (37 mm) and filter spacer with Na₂CO₃ impregnated backup pad, in a 3-piece cassette [SKC 225-9001]
Sampling time*

240-480 min

Sampling volume (TWA)*

480-960 L

Sampling flow rate (TWA)*

2 L/min

Sampling volume (STEL/Peak/C)*
Sampling flow rate (STEL/Peak/C)*
Analytical method instruments AAS/AES
Method reference OSHA ID-121 (fully validated)
Notes

Results will be reported from the elemental analysis for the element only; the stated identity of the actual sample contents is based on the assumption that the material sampled is as identified by the compliance officer using available documentation of materials and processes. An elemental result provided may be converted to the desired compound by multiplying the result by the appropriate stoichiometric factor.

A 91B report specific to the compound (including the stoichiometric conversion) may by be provided upon request by contacting the laboratory. The stoichiometric factor for sodium tetraborate, pentahydrate from sodium is 6.335.

Special requirements

* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Wipe Method
Sampler/Sampling media
Bulk Method
Bulk Method
On-Site Screening Techniques
Device
Model/Type
Sampling information
(see manufacturer instructions)
Exposure Limits
OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
NIOSH REL
Up to 10-hour TWA
(ST) STEL
(C) Ceiling
ACGIH TLV©
8-hour TWA
(ST) STEL
(C) Ceiling
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
PEL-TWA REL-TWA

1 mg/m³

TLV-TWA

2 mg/m³ (inhalable particulate matter) [2004]

PEL-TWA

5 mg/m³

PEL-STEL REL-STEL TLV-STEL

6 mg/m³ (inhalable particulate matter) [2004]

PEL-STEL
PEL-C REL-C TLV-C PEL-C
Skin notation

NA

Skin notation

N

Skin notation

N

Skin notation

N

Notes:

Not established

Notes: Notes: Notes:
Health factors:  See NIH-NLM PubChem. IDLH
Carcinogenic classifications: Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Last Updated Date : 01/12/2021