Page:NIOSH Manual of Analytical Methods - 2011.pdf/1

 FORMIC ACID

HCOOH

MW: 46.03

METHOD: 2011, Issue 1

CAS: 64-18-6

2011

RTECS: LQ4900000

EVALUATION: PARTIAL

OSHA : 5 ppm NIOSH: 5 ppm ACGIH: 5 ppm (1 ppm = 1.882 mg/m 3 @ NTP)

PROPERTIES:

Issue 1: 15 August 1994

liquid; BP 107 °C; d 1.22 g/mL (90% solution) @ 20 °C; VP 4.7 kPa (33 mm Hg); vapor density (air = 1) 1.6; colorless; pungent odor

SYNONYMS: hydrogencarboxylic acid; methanoic acid

SAMPLING SAMPLER:

FILTER + SOLID SORBENT TUBE (PTFE membrane, 5-µm + washed, silica gel, 400 mg/200 mg)

FLOW RATE:

0.05 to 0.2 L/min

VOL-MIN: -MAX:

1 L @ 5 ppm 24 L

SHIPMENT:

routine

SAMPLE STABILITY:

1 week @ 25 °C

BLANKS:

2 to 10 field blanks per set

ACCURACY RANGE STUDIED:

not studied

BIAS:

not determined

ˆ ): not determined OVERALL PRECISION (S rT ACCURACY:

not determined

MEASUREMENT TECHNIQUE:

ION CHROMATOGRAPHY, CONDUCTIVITY DETECTION

ANALYTE:

formate ion

DESORPTION:

10 mL deionized water; stand 5 minutes

INJECTION VOLUME:

50 µL

ELUENT:

2.5 mM Na 2B4O 7·10 H 2O, 2.0 mL/min

COLUMN:

Dionex HPIC-AG4 guard, HPIC-AS4 anion separator, anion micromembrane suppressor

DETECTOR:

conductivity, 10 µS full scale

CALIBRATION:

standard solutions of formate spiked onto sample media

RANGE:

6 to 100 µg formate per sample [1]

ESTIMATED LOD: 2 µg formate per sample [2,3] PRECISION(Sr):

0.026 @ 106 to 426 µg per sample [2] 0.097 @ 10 to 80 µg per sample [3]

APPLICABILITY: The working range is 0.13 to 12 ppm (0.25 to 22 mg/m 3) for a 24-L air sample.

INTERFERENCES: None identified.

OTHER METHODS: This is a modification of Method 7903 (Acids, inorganic) and revises Method S173 [1,3].

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