Reported in EPA TSCA Inventory.

OSHA PEL: Total Dust: TWA 10 mg/m³; Respirable Fraction: TWA 5 mg/m³
ACGIH TLV: TWA 10 mg/m³
DFG MAK: 15 mg/m³

 For occupational chemical analysis use NIOSH: Nuisance Dust, Total, 0500; Nuisance Dust, Respirable, 0600.

The Boron oxide, with the CAS registry number 1303-86-2,is also known as Diboron trioxide; Boric oxide; Boron trioxide. It belongs to the product categories of Industrial/Fine Chemicals;Inorganics;metal oxide. This chemical's molecular formula is B₂O₃ and molecular weight is 69.62.Its EINECS number is 215-125-8. What's more,Its systematic name is Boron oxide. It is a white powder or glassy flakes which is stable,moisture sensitive and incompatible with water.It is irritating to eyes, respiratory system and skin.When you use it ,wear suitable gloves and eye/face protection. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. Boron oxide can be prepared by treating borax with sulfuric acid in a fusion furnace. Keep the temperatures is above 750 °C, separate the molten boron oxide layer out from sodium sulfate. Then decant, cool and obtain this product in 96-97% purity.

Physical properties about Boron oxide are:
(1)#H bond acceptors:  3; (2)#H bond donors:  0; (3)#Freely Rotating Bonds:  2; (4)mp: 450 °C(lit.); (5)bp: 1860 °C; (6)density: 2.46 g/mL at 25 °C(lit.); (7)vapor density: >1 (vs air); (8)Fp: 1860°C; (9)Water Solubility: 36 g/L (25 oC); (10)Merck: 14,1337.

You can still convert the following datas into molecular structure:
(1)SMILES:O=BOB=O;
(2)Std. InChI:InChI=1S/B2O3/c3-1-5-2-4;
(3)Std. InChIKey:JKWMSGQKBLHBQQ-UHFFFAOYSA-N.

Uses of Boron oxide:
Boron oxide is used as a flux and also used for glass, enamel, production of boron compounds . In the color TVset industry, it's used as adulterate source for the  silicon source and the flux when silicate decomposes. It can also be used for the manufacture of boron. Concentrated boric anhydride solutions also can be used as hardeners of formo-phenolic resols, more particularly for the manufacture of laminates comprising glass fibers and formo-phenolic resols. In organic synthesis, Boric anhydride can play an important role, for example, when use carboxylic acid and phenol to prepare carboxylic esters of phenols, if Boric anhydride exits in the reaction solution, the process can improved.
 
The toxicity data of Boron oxide are as follows: