
Overview Back to Top
The Atmospheric Research Laboratory (ARL) at the University of Colorado Boulder’s Institute of Arctic and Alpine Research (INSTAAR) operates several analytical systems for qualitative and quantitative analyses of volatile organic compounds (VOC) in air samples. Since 2004, the ARL, in collaboration with the NOAA Global Monitoring Division, has been monitoring VOCs in weekly pairs of samples received from over 45 sites around the world. This is the most extensive global VOC monitoring currently operated around the world. A detailed program description is presented here.
On a second analytical system, VOCs and methane can be analyzed from glass flasks, Summa stainless steel canisters, and programmable flask packages. In recent years, these tools have been extensively applied in both background monitoring and research of VOC emissions from traffic, industrial operations, and oil and natural gas operations.
The ARL offers these VOC analyses to agencies and community members on a per sample or contract basis. We have ~25 years of experience in atmospheric VOC monitoring. We can provide guidance in sampling plans and make available sampling apparatus, glass flasks, and Summa canisters, or analyze VOC in whole air samples provided to us. We are capable of working with other collection methods on a case by case basis, as well.
Capabilities Back to Top
Samples are analyzed using an automated instrument with drying/pre-focusing of VOC in sample air followed by gas chromatography separation with mass spectrometry/flame ionization detection (GC-MS/FID). A wide range of VOC can be identified using the MS. Quantification is typically accomplished using the higher accuracy FID. Quantified chemical VOC species include saturated and unsaturated hydrocarbons, light alkanes, heavy alkanes, and aromatics.
Summa Cannisters Back to Top
Summa
Canisters
are
6
liter
stainless
steel
containers.
We
have
a
series
of
passive
flow
controllers
that
can
be
used
for
time-integrated
sampling
by
gradually
filling
canisters
over
periods
from
3
hours
up
to
several
days.
Flow
controlling
regulators
are
attached
to
the
top
of
the
canister
(see
picture
below).
Programmable
timers
can
be
added
to
this
sampling
package
to
allow
filling
canisters
only
during
certain
time
intervals
or
times
of
day.



Programmable Flask Packages Back to Top
Programmable
Flask
Packages (PFPs)
contain
twelve
0.7
L
borosilicate
glass
flasks,
stacked
in
two
rows
of
six.
PFPs
are
filled
using
a
programmable
compressor
package
(PCP)
that
includes
two
pumps
that
control
flow
rates
and
the
flasks
filling
pressure.
A
data
logging
and
control
system
controls
when
the
flasks
open
and
close,
and
can
store
a
sampling
plan
and
fill
pressure
for
all
samples.
These
air
samples
are
analyzed
on
the
same
analytical
system
as
for
the
Summa
cannisters.
Uncertainties and Precision Back to Top
We maintain a series of quantitative calibration standards for high accuracy quantification of methane and VOCs. Standards include whole air and synthetic mixtures. We maintain several standards at higher than (typical) ambient VOC mole fractions for accurate quantification of elevated VOC that can be observed in the vicinity of oil and natural gas operations. Currently, nine standards are available with a wide range of VOC. Our calibration scale is regularly compared with national and international partners to ascertain our lab’s calibration scale. ARL has been audited two times by the World Calibration Centre for VOC. During both audits all reported VOC were quantified within the quality objectives of the World Meteorological Organization Global Atmospheric Watch.
Most
of
the
VOC
species
are
quantifiable
at
detection
limits
down
to
single
parts
per
trillion
levels
(pptv),
Measurement
uncertainties
for
glass
flasks,
Summa
canisters,
and
PFPs
for
C2-C6
alkanes
are
between
2–5%
at
mixing
ratios
>100
ppt,
and
≤5
ppt
for
results
<100
ppt.
Measurement
uncertainties
are
approximately
2x
higher
for
acetylene
and
benzene.
Methane
quantification
results
have
a
~0.3%
uncertainty
for
single
injections,
and
at
<0.1%
uncertainty
for
multiple
runs.
Posters from our VOC monitoring work Back to Top

Evaluation and Application of a Solid Adsorbent Method for Monitoring Exposure to Volatile Organic Compounds from Oil and Gas Operations, 2014. K. R. Smith, D. Helmig, A. Lewis, C. R. Thompson, J. M. Evans, W. Wang, and J. Hueber.

Influence of Emissions from Oil and Gas Development on Elevated Ozone in the Northern Colorado Front Range, 2014. Jason Evans, Detlev Helmig, and Chelsea Thompson.

Influence of Oil and Gas Emissions on Ambient Atmospheric Volatile Organic Compounds in Residential Areas of Northeastern Colorado, 2014. C. R. Thompson, J. M. Evans, K. R. Smith, W. Wang, J. Hueber, and D. Helmig.
Publications from our VOC monitoring work Back to Top
Helmig
D.,
Rossabi
S.,
Hueber
J.,
Tans
P.,
Montzka
S.A.,
Masarie
K.,
Thoning
K.,
Plass-Duelmer
C.,
Claude
A.,
Carpenter
L.J.,
Lewis
A.C.,
Punjabi
S.,
Reimann
S.,
Vollmer
M.K.,
Steinbrecher
R.,
Hannigan
J.W.,
Emmons
L.K.,
Mahieu
E.,
Franco
B.,
Smale
D.,
and
Pozzer
A.
(2016)
Reversal
of
global
atmospheric
ethane
and
propane
trends
largely
due
to
US
oil
and
natural
gas
production,
Nature
Geosci,
9,
490-495.
(link
to
article)
Oltmans
S.J.,
Karion
A.,
Schnell
R.C.,
Pétron
G.,
Sweeney
C.,
Helmig
D.,
Montzka
S.A.,
Wolter
S.,
Neff
D.,
Miller
B.R.,
Hueber
J.,
Conely
S.,
and
Johnson
B.J.
(2016)
O3,
CH4,
CO2,
CO,
NO2,
and
NMHC
aircraft
measurements
in
the
Uinta
Basin
oil
and
gas
development
region
under
exceptional
high
ozone
and
non-ozone
producing
winter
conditions.
Elementa,
in
press.
Ahmadov R. et al. (2015) Understanding high wintertime ozone pollution events in an oil- and natural gas-producing region of the western US. Atmos. Chem. Phys. 15, 411-429. (Link to article)
Thompson C., Hueber J., and Helmig D. (2014) Influence of oil and gas emissions on ambient atmospheric non-methane hydrocarbons in residential areas of Northeastern Colorado. Elem. Sci. Anth. 3, 000035, 1-17, doi: 10.12952/journal.elementa.000035. (Link to article)
Edwards P.M. et al. (2014) High winter ozone pollution from carbonyl photolysis in an oil and gas basin. Nature 514, 351-354. (Link to article)
Oltmans S.J., Karion A., Schnel, R.C., Pétron G., Sweene, C., Wolter S., Neff D., Montzka S.A., Miller B. R., Helmig D., Johnson B.J., and Hueber J. (2014) A high ozone episode in winter 2013 in the Uinta Basin oil and gas region characterized by aircraft measurements, Atmos. Chem. Phys. Discuss. 14, 20117-20157, doi:10.5194/acpd-14-20117-2014. (Link to article)
Pétron G. et al. (2014) A new look at hydrocarbons emissions from oil and gas operations in the Colorado Denver-Julesburg Basin. J. Geophys. Res. 119, 6836-6852. (Link to article)
Edwards P.M. et al. (2013) Ozone photochemistry in an oil and natural gas extraction region during winter: simulations of a snow-free season in the Uintah Basin, Utah. Atmos. Chem. Phys. 13, 8955-8971. (Link to article)
Contact Information Back to Top
Detlev
Helmig
Institute
of Arctic
and
Alpine
Research
University
of Colorado
4001
Discovery
Drive
Boulder,
CO 80303,
USA
001
303
492-2509
detlev.helmig@colorado.edu