METHYLAL (DIMETHOXY-METHANE) (DIMETHOXYMETHANE) | Occupational Safety and Health Administration

METHYLAL (DIMETHOXY-METHANE) (DIMETHOXYMETHANE)†

Chemical Identification
Chemical Identification
CAS #	109-87-5
Formula	C₃H₈O₂
Synonyms	dimethoxymethane; formaldehyde dimethylacetal; methoxymethyl methyl ether; methylene dimethyl ether

Physical Properties
Physical Properties
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

Monitoring Methods Used by OSHA
Monitoring Methods Used by OSHA
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 Method
Wipe Method
Sampler/Sampling media

Bulk Method
Bulk Method

On-Site Screening Techniques
On-Site Screening Techniques
Device	Infrared spectrophotometer
Model/Type	Miran 1A & 1B
Sampling information (see manufacturer instructions)	0.1 ppm@9.5 µm

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	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: See 29 CFR 1910.1000 Table Z-1.		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
Additional Resources and Literature References
NOAA: CAMEO Chemicals - Methylal NIOSH: Pocket Guide to Chemical Hazards - Methylal Literature References ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methylal. See annual publication for most recent information.

Last Updated Date : 01/05/2021