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Diss Factsheets
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EC number: 231-143-9 | CAS number: 7440-33-7
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
![](https://poisoncentres.echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_physical-and-chemical-properties.png)
Additional physico-chemical information
Administrative data
- Endpoint:
- other: dust cloud explosion
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- N/A to 2004-05-01
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- test procedure in accordance with generally accepted scientific standards and described in sufficient detail
- Remarks:
- Well documented, scientifically sound study
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 004
- Report date:
- 2004
Materials and methods
Test guideline
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- Explosion indices were measured using a standard method in a 20-I-spherical combustion chamber
- GLP compliance:
- not specified
Test material
- Reference substance name:
- tungsten metal
- IUPAC Name:
- tungsten metal
- Reference substance name:
- Tungsten
- EC Number:
- 231-143-9
- EC Name:
- Tungsten
- Cas Number:
- 7440-33-7
- Molecular formula:
- W
- IUPAC Name:
- tungsten
- Details on test material:
- - Name of test material (as cited in study report): tungsten
- Analytical purity: 99.9%
Constituent 1
Constituent 2
Results and discussion
- Results:
- Explosive (not specified): yes, only for tungsten particles of 0.6-0.9 um and conetrations of 450 g/m3 or larger. Increasing concentrations at this size required increasing pressures for ignition from 0.2 bars at 450 g/m3 to 3.9 Bars at 2000 g/m3.
Any other information on results incl. tables
The coarser dusts (12 µm and 5 µm) did not appear to explode under the standard method conditions in the concentration range of 250 to 6000 g/m3 (12-µm dust) and 300 to 7000 g/m3 (5-µm dust), respectively. For the smallest particle size tested (0.6 -0.9 µm), the lower explosion limit was measured to be 450 g/m3. Starting from this limit, the maximum overpressure increased first with concentration, reached its maximum of at least 4.7 bar at 5000 g/m3 and then slowly decreased. The pressure rise rate showed the same behavior, its maximum was reached at the same concentration to be at least 260 bar/s. These values were measured at initial pressure lower 1 bar due to rather high explosive concentrations; the correction to the 1 bar initial pressure gives the calculated values of 5.7 bar and 310 bar/s, respectively.
Applicant's summary and conclusion
- Conclusions:
- The 12 µm and 5 µm tungsten dusts were not explosive under standard conditions, as tested using a 20-I-spherical combustion chamber. However, the finest particle size tested (0.6-0.9 µm) was determined to be explosive in this test under a wide range of concentrations (450 g/m3- 7500 g/m3).
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