silicon dioxide

(redirected from Crystalline silica)
Also found in: Dictionary, Thesaurus, Medical.
Related to Crystalline silica: Amorphous silica

silicon dioxide:

see silicasilica
or silicon dioxide,
chemical compound, SiO2. It is insoluble in water, slightly soluble in alkalies, and soluble in dilute hydrofluoric acid. Pure silica is colorless to white.
..... Click the link for more information.

silicon dioxide

[′sil·ə·kən dī′äk‚sīd]
(inorganic chemistry)
SiO2 Colorless, transparent crystals, soluble in molten alkalies and hydrofluoric acid; melts at 1710°C; used to make glass, ceramic products, abrasives, foundry molds, and concrete.

silica, silicon dioxide

A white or colorless substance, nearly insoluble in water and in all acids except hydrofluoric; extremely hard; fuses to a colorless amorphous glass.

silicon dioxide

(SiO2) A hard, glassy mineral found in materials such as rock, quartz, sand and opal. In metal oxide semiconductor (MOS) chip fabrication, silicon dioxide is used to create the insulation layer between the metal gates of the top layer and the silicon elements below. See silica gel.
References in periodicals archive ?
workers remain potentially exposed to respirable crystalline silica (5).
The presence of crystalline silica needs to be clearly labelled; if it's in a greater concentration than 0.1% then a safety data sheet must accompany any products where this is the case.
1999); and crystalline silica linked with rheumatoid arthritis, systemic sclerosis, systemic lupus, glomerulonephritis, and small-vessel vasculitides (Koeger et al.
Research conducted by Burns, Mozzon, and Ottoboni has indicated that operators of heavy equipment are frequently exposed to airborne dust containing concentrations of crystalline silica that exceed permissible exposure limits (PELs) [2-4].
OSHA's Crystalline Silica Rule: What Should Your Foundry Be Doing Now?
Even though all trade contractors will be required to ensure that they are limiting exposure to crystalline silica on a jobsite, the general contractor will be held responsible for their sub-contractors, too.
The timing of this year's event coincides with the September 23rd 2017 enforcement of the Occupational Safety and Health Administration (OSHA)'s Crystalline Silica Standard for Construction under 29 CFR 1926.1153.
For Occupational Health: milestones set were that by December 2024, 95% of all exposure measurement results will be below the milestone level for respirable crystalline silica of 0.05 mg/m3, for coal dust respirable particulate of 1.5 mg/m3 (
Occupational Safety and Health Administration (OSHA) will soon publish a final workplace exposure standard for crystalline silica that will cut the permissible exposure limit in half.
Polyfil 35 is said to offer acid resistance, reinforcement and very low crystalline silica and salt content.
A high proportion of the radiographs suggested silicosis, a disease caused by inhalation of crystalline silica. Surface coal mine operators should monitor worker exposures closely to ensure that both respirable dust and silica are below recommended levels to prevent CWP.