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1,3-BUTADIENE

1024

H₂C=CHHC=CH₂

MW: 54.09

CAS: 106-99-0

METHOD: 1024, Issue 2

EVALUATION: FULL

Issue 1: 15 August 1987
Issue 2: 15 August 1994

OSHA:

1000 ppm

NIOSH:

lowest feasible; suspect carcinogen

PROPERTIES:

gas; vapor density 1.9 (air = 1); BP –4.4 °C; explosive range 2.0 to 11.5% v/v in air

ACGIH:

10 ppm; suspect carcinogen (1 ppm = 2.21 mg/m³ @ NTP)

SYNONYMS:

butadiene; biethylene; divinyl

SAMPLING

SAMPLER:

SOLID SORBENT TUBE
(coconut charcoal, 400- and 200-mg inseparate tubes)

FLOW RATE:

0.01 to 0.5 L/min

VOL-MIN:

5 L @ 100 ppm

-MAX:

25 L

SHIPMENT:

separate front and back tubes, chill below –4 °C

SAMPLE STABILITY:

at least two months for quality assurance blind spikes stored in a freezer

BLANKS:

2 to 10 field blanks per set

ACCURACY

RANGE STUDIED:

0.19 to 19 mg/m³ (25-L samples)

BIAS:

0.1%

OVERALL PRECISION (Ŝ_rT):

0.060

ACCURACY:

±11.32%

MEASUREMENT

TECHNIQUE:

GAS CHROMATOGRAPHY, FID

ANALYTE:

1,3-butadiene

DESORPTION:

4 mL methylene chloride; 30 min

INJECTION:

1 µL

TEMPERATURE-INJECTION:

200 °C

-DETECTOR:

250 °C

-COLUMN:

see APPENDIX A

CARRIER GAS:

helium

MAKEUP GAS:

nitrogen, 30 mL/min

COLUMNS:

fused silica, 10 m × 0.50-mm ID, 1.8-µm CP WAX 57 CB (backflushable pre-column), and 50 m × 0.32-mm ID, Al₂O₃/KCl PLOT (see APPENDIX A)

CALIBRATION:

vapor-spiked sampling media

RANGE:

1 to 480 µg per sample

ESTIMATED LOD:

0.2 µg per sample

PRECISION(S₁):

0.025

APPLICABILITY:

The working range is 0.02 to 100 ppm (0.04 to 220 mg/m³) for a 25-L air sample. At the higher levels, desorbed samples may require dilution. Below 0.9 mg/m³ (0.4 ppm), the desorption efficiency falls below 75% and allowance should be made for decreased accuracy.

INTERFERENCES:

Pentane, methyl acetylene, or vinylidene chloride may chromatographically interfere at high levels. High humidity (>80% RH) or other hydrocarbons present at permissible levels may significantly decrease the sampler’s capacity for 1,3-butadiene.

OTHER METHODS:

This revises Method S91 [1].

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition