Page:NIOSH Manual of Analytical Methods - 2550.pdf/1
BENZOTHIAZOLE IN ASPHALT FUME
C7H5SN
MW: 135.19
METHOD: 2550, Issue 1
CAS: 95-16-9
2550
RTECS: DL0875000
EVALUATION: PARTIAL
OSHA : no PEL NIOSH: no REL ACGIH: no TLV
PROPERTIES:
Issue 1: 15 January 1998
liquid; d 1.246 g/mL @ 20 C; MP 2 C; BP 231 C; vp 4.5 kPa (34.0 mm Hg) @ 131 C; vapor density 4.7 (air = 1)
SYNONYMS: Benzosulfonazole; 1-Thia-3-azaindene SAMPLING SAMPLER:
FILTER + SORBENT TUBE (2-µm, 37-mm, PTFE + XAD-2, 100/50 mg)
FLOW RATE:
1.0 to 2.0 L/min
VOL-MIN: -MAX: 960 L
480 L
SHIPMENT:
Ship samples with refrigerant packs
SAMPLE STABILITY:
ca. 28 days @ 4 C [1]
BLANKS:
2 to 10 field blanks per set
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, SULFUR CHEMILUMINESCENCE DETECTOR
ANALYTE:
benzothiazole
DESORPTION:
4 mL hexane; stand 30 minutes
INJECTION VOLUME:
1 µL
TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:
275 C 1000 C 50 C, 1.0 min; 15 C/min to 225 C, hold 15 min; 6 C/min to 320 C
CARRIER GAS:
Helium @ 2.4 mL/min (splitless)
COLUMN:
capillary, 30 m, 0.32-mm ID, 1.0-µm film, 100% dimethyl polysiloxane, Rtx-1® or equivalent
CALIBRATION:
solutions of benzothiazole in hexane
RANGE:
1.0 to 250 µg per sample
ACCURACY
RANGE STUDIED:
not studied
BIAS:
not determined
OVERALL PRECISION ( ACCURACY:
rT
): not determined not determined
ESTIMATED LOD: 0.30 µg per sample (instrumental) [1] PRECISION ( r):
0.5 @ 1.0 to 20 µg per sample
APPLICABILITY: The working range is 0.002 to 0.5 mg/m3 for a 480-L air sample. This method was developed to determine benzothiazole in the presence of other sulfur compounds in asphalt fume samples (see Figure 1). This method may be used in conjunction with method 5800, Polycyclic Aromatic Compounds, Total [2]. An aliquot of the desorbed sample from method 5800 can be analyzed for benzothiazole by this method, since the sampler and desorbing solvent are the same.
INTERFERENCES: None identified; however, compounds with a similar retention time may interfere. Positive identification may be confirmed by dual column chromatography using an appropriate alternative capillary column. Identification can also be confirmed by mass spectrometry.
OTHER METHODS:None identified.
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition