Page:NIOSH Manual of Analytical Methods - 2507NIT.pdf/1

Rh (CH₂ONO₂)CHONO₂

METHOD: 2507, Issue 2

OSHA: C 0.2 ppm (skin)

NIOSH: STEL 0.1 mg/m³ (skin)

ACGIH: 0.05 ppm (skin) (1 ppm = 9.29 mg/m³ @ NTP)

PROPERTIES: liquid; MP 3 to 13 °C; d 1.592 g/mL @ 25 °C; VP 0.034 Pa (0.00026 mm Hg; 0.34 ppm) @ 20 °C

SYNONYMS: NG; 1,2,3-propanetriol trinitrate.

SAMPLER: SOLID SAMPLER TUBE (Tenax-GC, 100 mg/50 mg)

FLOW RATE: 0.2 to 1.0 L/min

VOL-MIN: 3 L @ 1 mg/m³

-MAX: 100 L

SHIPMENT: routine

SAMPLE STABILITY: at least 25 days @ 25 °C [1]

BLANKS: 2 to 10 field blanks per set

RANGE STUDIED: 0.6 to 3.2 mg/m³ [2,3] (15-L samples)

BIAS: - 0.02%

OVERALL PRECISION ((rT​):0.104[2): 0.104 [2]

ACCURACY: ±20.3%

TECHNIQUE: GAS CHROMATOGRAPHY, ECD

ANALYTE: nitroglycerin

DESORPTION: 2 mL ethanol; stand 30 min

INJECTION VOLUME: 2 μL

TEMPERATURE-INJECTION: 160 °C

-DETECTOR: 280 °C

-COLUMN: 125 °C

CARRIER GAS: 95% argon/methane, 75 mL/min

COLUMN: glass, 1 m x 4-mm, 2-mm ID 10% OV-17 on 60/80 mesh Gas Chrom Q

CALIBRATION: solutions of NG in ethanol

RANGE: 3 to 45 μg per sample

ESTIMATED LOD: 0.6 μg per sample

PRECISION (Sr): 0.051 [2]

APPLICABILITY: This method is applicable to the simultaneous determination of nitroglycerin and ethylene glycol dinitrate (EGDN). The working range for both compounds is 0.02 to 0.3 ppm ( 0.2 to 3 mg/m³) for a 15-L air sample, provided that the linear range of the ECD is not exceeded.

INTERFERENCES: A high concentration of 2-hydroxyethyl nitrate (ethylene glycol mononitrate) tails into the EGDN peak but does not prevent a satisfactory determination of EGDN.

OTHER METHODS: This method combines and replaces Methods S216 [2,5] and P&CAM 203 [4]