MAGNESITE†

Chemical Identification
Chemical Identification
CAS # 546-93-0; 13717-00-5
Formula

MgCO₃

Synonyms

carbonate magnesium; hydromagnesite; magnesium carbonate; magnesium(II) carbonate

Physical Properties
Physical Properties
Physical description White, odorless, crystalline powder.
Boiling point decomposes Molecular weight 84.3
Freezing point/melting point 662°F (decomposes) Vapor pressure 0 mmHg (approx)
Flash point Vapor density
Specific gravity 2.96 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
Monitoring Methods Used by OSHA
Analyte code (IMIS no.) 1615 (total); request using analyte code 9135 M113 (resp); request using analyte code 9130
Sampling group
Sampler/Sampling media Tared low-ash 37 mm PVC filter, 5 microns [SLTC108] Tared low-ash 37 mm PVC filter, 5 microns, preceded by 10 mm nylon Dorr-Oliver cyclone for respirable samples. [SLTC108]
Sampling time*

240-480 min

240-480 min

Sampling volume (TWA)*

960 L

816 L

Sampling flow rate (TWA)*

2 L/min

1.7 L/min ±5%

Sampling volume (STEL/Peak/C)*
Sampling flow rate (STEL/Peak/C)*
Analytical method instruments Gravimetric Gravimetric
Method reference OSHA PV2121 (partially validated) OSHA PV2121 (partially validated)
Notes

Samples are analyzed gravimetrically. Results will be qualified based on the assumption that the material sampled is as identified by the compliance officer using available documentation of materials and processes; no further work on the sample will be performed due to method limitations.

Samples are analyzed gravimetrically. Results will be qualified based on the assumption that the material sampled is as identified by the compliance officer using available documentation of materials and processes; no further work on the sample will be performed due to method limitations. The standard applies to the Respirable Fraction.

Special requirements

FOR TOTAL DUST SAMPLES, DO NOT USE A CYCLONE!!!

Samples must be collected with a Dorr-Oliver cyclone.

* 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
Wipe Method
Sampler/Sampling media
Bulk Method
Bulk Method
On-Site Screening Techniques
On-Site Screening Techniques
Device
Model/Type
Sampling information
(see manufacturer instructions)
Exposure Limits
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

15 mg/m³ (total dust), 5 mg/m³ (respirable fraction)

REL-TWA

10 mg/m³ (total), 5 mg/m³ (resp)

TLV-TWA PEL-TWA

10 mg/m³ (total dust), 5 mg/m³ (respirable fraction)

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

N

Skin notation

N

Skin notation

N

Skin notation

N

Notes:

See 29 CFR 1910.1000 Table Z-1.

Notes: Notes:

See Appendix B: Particles (insoluble or poorly soluble) Not Otherwise Specified (PNOS)

Notes:

as Particulates not otherwise regulated. See also footnote [n]

Health factors:  See NIH-NLM PubChem. IDLH
Carcinogenic classifications: Not listed Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Magnesite

NIOSH: Pocket Guide to Chemical Hazards - Magnesite

Literature References

  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) -Appendix B: Particles (insoluble or poorly soluble) Not Otherwise Specified (PNOS). See annual publication for most recent information.

Last Updated Date : 01/04/2021