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METHYLAL (DIMETHOXY-METHANE) (DIMETHOXYMETHANE)†
| CAS # | 109-87-5 |
|---|---|
| Formula |
C₃H₈O₂ |
| Synonyms |
dimethoxymethane; formaldehyde dimethylacetal; methoxymethyl methyl ether; methylene dimethyl ether |
| Physical description | Colorless liquid with a chloroform-like odor. | ||
|---|---|---|---|
| Boiling point | 111°F | Molecular weight | 76.1 |
| Freezing point/melting point | -157°F | Vapor pressure | 330 mmHg |
| Flash point | -26°F (open cup) | Vapor density | 2.6 |
| Specific gravity | 0.86 | Ionization potential | 10.00 eV |
| Lower explosive limit (LEL) | 1.6% | Upper explosive limit (UEL) | 17.6% |
| NFPA health rating | 1 | NFPA fire rating | 3 |
| NFPA reactivity rating | 1 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1655 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] |
| Sampling time* |
|
| Sampling volume (TWA)* |
1-3 L |
| Sampling flow rate (TWA)* |
0.01 - 0.2 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FID |
| Method reference | NIOSH 1611 (fully validated) |
| Notes |
|
| 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 Sampler/Sampling media |
|
|---|---|
| Bulk Method |
|
| Device | Infrared spectrophotometer |
|---|---|
| Model/Type | Miran 1A & 1B |
|
Sampling information (see manufacturer instructions) |
0.1 ppm@9.5 µm |
|
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 |
|||||
|---|---|---|---|---|---|---|---|
| PEL-TWA |
1000 ppm (3100 mg/m³) |
REL-TWA |
1000 ppm (3100 mg/m³) |
TLV-TWA |
1000 ppm [1970] |
PEL-TWA |
1000 ppm (3100 mg/m³) |
| 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: |
Notes:
|
Notes:
|
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
2200 ppm |
|||||
| Carcinogenic classifications: Not listed |
Notes:
10% of LEL |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
|
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methylal NIOSH: Pocket Guide to Chemical Hazards - Methylal Literature References
|
Last Updated Date : 01/05/2021