Screening Sorbent Tubes
Multiple Sorbents for Multiple Contaminants
- Cost-effective
- One inexpensive and highly sensitive tube screens for many
compounds
- Time-saving
- Quickly determine what compounds are present
- Sampling for multiple compounds in unknown atmospheres
- Hydrocarbons, alcohols, aromatics, aldehydes, sulfides, ketones,
esters, and halogenated compounds
- Tubes can be used with a personal sampling pump
- Wide range of monitoring applications
Screening
Sorbent Tubes Product Data Bulletin (PDF)
SKC Screening Sorbent Tubes
Designed to collect a wide array of compounds, SKC thermal desorption screening
tubes contain multiple layers of different sorbent materials. This specialized
construction allows for the collection of different classes of compounds including
both polar and non-polar compounds in the C2 to C30 range
to be collected with one tube. After identifying the contaminants, further
sampling using methods for specific compounds can be used for quantification.
Applications
- Workplace background exposure levels
- Personal exposure levels
- Unknown atmospheres
- Sick Building Syndrome (SBS)
- Process changeover/maintenance exposures
- Confined areas
- Stack emissions/vent gases
- Hazmat
Methods for Screening Tubes
NIOSH Method 2549† is
a screening method for sampling volatile organic compounds (VOCs) in the C5 to
C16 range. VOCs are sampled by drawing air through the sorbent tube
using a personal sampling pump at a flow rate of 50 ml/min. Analysis is by
thermal desorption/gas chromatography-mass spectrometry (TD/GC-MS). NIOSH 2549
specifies a thermal desorption tube containing sorbent layers of graphitized
carbon and carbon molecular sieve (CMS), but allows other sorbent combinations
to be used. In particular, if the compounds of interest are known, specific
sorbents that work best for those compounds may be substituted.
† NIOSH Manual
of Analytical Methods, Fourth Edition, May 15, 1996
EPA Method IP-1B* applies to
sampling a variety of VOCs having a boiling point range of approximately 80
to 200 C. The VOCs are sampled by drawing indoor air through the sorbent tube
using a personal sampling pump at a flow rate of 12 to 150 ml/min depending
on the compound. Analysis is by TD/GC-MS. EPA IP-1B specifies a thermal desorption
sorbent tube containing Tenax®, but also includes an alternative multi-bed
sorbent tube containing CMS and graphitized carbon.
* Compendium of Methods
for the Determination of Air Pollutants in Indoor Air (EPA/600/4-90/010 April,
1990)
The TDT Air Scan™ screening tube was developed using
a combination of instrument technology and methodology. Designed to trap both
polar and non-polar compounds in air, this multi-bed sorbent tube containing
CMS, graphitized carbon, and Tenax GR can be used for the qualitative identification
of multiple compounds. The analytical method is used to determine what compounds
are present as well as what compounds are not. Samples are taken using a personal
sampling pump. For analysis using Prism Analytical's sensitive analytical technique,
the tube must be sent to Prism Analytical, Inc., 1200 N. Fancher, Mt. Pleasant,
MI 48858, (989-772-5088).
Custom Screening Tubes
SKC currently manufactures the sorbent combinations listed
below as standard items, but specialty tubes can be made for custom applications
or
different thermal desorbers. Developments in sorbent technology have brought
about superior materials for the collection of VOCs in the environment. SKC
sorbent materials meet stringent specifications and undergo extensive cleaning
procedures
required for screening tube applications.
Sorbents Used in Screening Tubes
Anasorb® CMS (Carbon Molecular Sieve) is a traditional
sorbent for trapping low boiling point compounds (-60 to 80 C) in the C2 through
C5 range. CMS is comparable to Carbosieve® S-III and Carboxen® 1000
and 1003.
Anasorb GCB1 (Graphitized Carbon Black 1) is a sorbent for
sampling intermediate to highly volatile compounds (bp > 75 C) in the C5 through
C14 range. It is equivalent to Carbotrap® B.
Anasorb GCB2 (Graphitized Carbon Black 2) is a sorbent for
sampling semi-volatile compounds in the C8 through C20 range.
It is equivalent to Carbotrap C.
Tenax GR is a 70% Tenax TA/30% graphite composite sorbent
for trapping low, medium, and high boiling point compounds (bp 100 to 450 C)
in the C7 through C30 range
Ordering Information Online
Ordering
Applications†
|
Sorbent
(Amount) |
Description
Size
OD x L |
Desorber
|
Cat. No.
|
EPA IP-1B,
NIOSH 2549 |
Anasorb CMS/GCB1/ GCB2
(100 mg/150 mg/250 mg) |
Glass, open
6 x 115 mm |
Dynatherm
|
226-330 *
|
| Screening Multiple Compounds |
Anasorb CMS/GCB1/Tenax GR
(100 mg/100 mg/100 mg) |
Glass, open
1/4 x 41/2 inches |
#
|
226-352 *
|
| † |
Refer to the method for specific compound listings. |
| * |
Tubes are chemically conditioned before shipping. If not
used within 30 days, they must be reconditioned. |
| # |
Proprietary method for analysis by thermal desorption using
a sensitive analytical technique developed by Prism Analytical Technologies,
Inc, call 989-772-5088 |
Screening
Sorbent Tubes Product Data Bulletin (PDB)
This page was last modified June 28, 2010
