Page:NIOSH Manual of Analytical Methods - 3512.pdf/1

 MALEIC ANHYDRIDE

C4H2O 3

MW: 98.06

METHOD: 3512, Issue 1

CAS: 108-31-6

3512

RTECS: ON3675000

EVALUATION: FULL

OSHA : 0.25 ppm TWA NIOSH: 0.25 ppm TWA ACGIH: 0.25 ppm TWA (1 ppm = 4.01 mg/m 3 @ NTP)

PROPERTIES:

Issue 1: 15 August 1994

solid; MP 53 °C; d 1.43 @ 22 °C; VP <0.16 mm Hg @ 20 °C; vapor density (air = 1) 3.38

SYNONYMS: 2,5-furandione; cis-butenedioic anhydride; toxilic anhydride

SAMPLING SAMPLER:

BUBBLER (15 mL distilled water)

MEASUREMENT TECHNIQUE:

HPLC, UV DETECTION

ANALYTE:

maleic anhydride

INJECTION VOLUME:

50 µL

FLOW RATE: 0.2 to 1.5 L/min VOL-MIN: -MAX: SHIPMENT:

40 L @ 1.0 mg/m 3 500 L

MOBILE PHASE:

0.5% dicyclohexylamine/0.5% formic acid/25% methanol/74% water, 1.7 mL/min

COLUMN:

µ-Bondapak C 18, 10-µm particle size, 30 cm x 3.9-mm ID or equivalent

DETECTOR:

UV @ 254 nm

CALIBRATION:

standard solutions of maleic anhydride in acetone and distilled water

RANGE:

36 to 1080 µg per sample [1]

plug inlet and outlet with Teflon plugs to prevent spillage during shipment.

SAMPLE STABILITY:

less than 7 days @ 25 °C

BLANKS:

2 to 10 field blanks per set

ACCURACY RANGE STUDIED: BIAS:

0.50 to 2.14 mg/m 3 [1] (340-L samples) - 6.7%

ˆ ): 0.063 [1] OVERALL PRECISION (S rT ACCURACY:

ESTIMATED LOD: 15 µg per sample [2] PRECISION (Sr):

0.035 @ 181 to 723 µg per sample [1]

± 19.0%

APPLICABILITY: The working range is 0.025 to 0.75 ppm (0.1 to 3 mg/m 3) for a 360-L air sample. This method does not distinguish between maleic anhydride and maleic acid, and has limited sample stability [1].

INTERFERENCES: Since maleic anhydride is converted to maleic acid, maleic acid can be considered an interference and will result in a positive bias.

OTHER METHODS: This revises Method P&CAM 302 [2]. Geyer and Saunders reported a modified mobile phase for the determination of maleic anhydride, but used the same sampling technique [3]. A method for the trace analysis of maleic a nhydride in workplace air was published by Kallio [4].

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94