DIMETHYLFORMAMIDE (See Method 2004, DIMETHYLACETAMIDE, for procedure)
O=CHN(CH3)
MW: 73.10
METHOD: 2004, Issue 2
CAS: 68-12-2
RTECS: LQ2100000
EVALUATION: FULL
OSHA : 10 ppm (skin) NIOSH: 10 ppm (skin) ACGIH: 10 ppm (skin) 1 ppm = 2.99 mg/m 3 @ NTP
PROPERTIES:
2004
Issue 1: 15 May 1989 Issue 2: 15 August 1994
liquid; d 0.95 g/mL @ 25 °C; BP 153 °C; MP -61 °C; VP 2.7 mm Hg @ 20 °C; explosive range in air (v/v) 2.2 to 15.2%
SYNONYMS: N-formyldimethylamine; DMF; N,N-dimethylformamide
SAMPLING SAMPLER:
SOLID SORBENT TUBE (silica gel, 150 mg/75 mg)
FLOW RATE:
0.01 to 1 L/min
VOL-MIN: -MAX:
15 L @ 30 mg/m 3 80 L
SHIPMENT:
routine
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, FID
ANALYTE:
dimethylformamide
DESORPTION:
1 mL methanol; 1 h in ultrasonic bath
INJECTION VOLUME:
5 µL
SAMPLE STABILITY:
at least 5 days @ 25 °C [1]
TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:
240 °C 320 °C 140 °C
BLANKS:
2 to 10 field blanks per set
CARRIER GAS:
N 2, 50 mL/min
COLUMNS:
1.5 m x 6-mm OD glass; 10% UCON 50-HB-5100, 2% KOH on 100/120 mesh Chromosorb WHP
CALIBRATION:
analyte in methanol
RANGE:
0.5 to 4 mg per sample [1,2]
ACCURACY RANGE STUDIED:
11 to 61 mg/m 3 [1]; (45-L samples)
BIAS:
- 1.1%
ESTIMATED LOD: 0.05 mg per sample [2]
ˆ rT): 0.056 [1] OVERALL PRECISION (S ACCURACY:
± 11.7%
PRECISION (Sr):
0.037 [1]
APPLICABILITY: The working range is 3.3 to 27 ppm (10 to 80 mg/m 3) for a 50-L air sample. The lower limit is determined by the desorption efficiency which must be determined over the range used. Silica gel has a high affinity for water; high r elative humidity may adversely affect the efficiency of analyte adsorption.
INTERFERENCES: None identified. Separation conditions (column, temperature, etc.) may be changed to circumvent problems. Alternate columns include: 60/80 mesh Chromosorb P coated with 20% UCON LB 550X and 2% KOH; 100/120 mesh Chromosorb WHP with 10% Carbowax 20M and 2% KOH; 100/120 mesh Chromosorb WHP with 10% SP-2250; and 30-m x 0.32-mm capillary coated with 0.5 µm DB Wax.
OTHER METHODS: This combines and replace Methods S254 and S255 [2].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
