United States
                 Environmental Protection
                 Agency
Office of
Underground Storage Tanks
Washington, D.C. 20460
EPA/530/UST-88/006
August 1988
SEPA       Leak  Lookout
                                                            , -  .... ... ..

                                             ij/ii^Iiisiis;;.-.^:;^;,1 \.rj',,:^ff^:9>l Recycled Paper


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     LEAK LOOKOUT
 Using External Leak Detectors to
Prevent Petroleum Contamination
from Underground Storage Tanks
   U.S. Environmental Protection Agency
   Office of Underground Storage Tanks
           August 1988

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                           Acknowledgement

The text of this brochure was prepared by John D. Kofler for EPA's Office of
Underground Storage Tanks.

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LEAK LOOKOUT
                                                                             PAGE1
Why Worry About Leak
Detection?
Because your tank or its piping may leak.
As many as 25 percent of all underground
storage tanks (USTs) may how be leaking.
Many more will leak in the near future—
possibly yours. In fact, your tank or its
piping might be leaking now, although you
may not know it.  If a tank system is past
its prime (that is, over 10 years old), espe-
cially if it's not protected against corrosion,
the potential for leaking increases dramati-
cally. Newer tank systems, particularly the
piping, can also leak. Don't let your profits
drain away.

Because it's the law. And it's the law for
a good reason.  Much of our country
depends upon ground water for drinking
water, and leaked or spilled petroleum can
contaminate this vital resource. Explo-
sions are another potential hazard of leaks.
Federal requirements for tank systems,
excluding home heating and small farm
tanks, will become effective at the end of
1988. Many State and local governments
already require specific steps to prevent,
detect, or clean up leaks; and others will
soon have similar requirements. Check
with your State and local governments to
learn what requirements apply to you.
                 *«  j«LJ
       uttiSw  **£**il
Because it's in your best interest. Leak-
ing UST sites can be very costly to clean
up. Imagine how much money you'd lose
if your tank could not be used for weeks
during lengthy cleanups or if local resi-
dents sued you for property damages. The
costs can run into the thousands—perhaps
as much as $500,000 and more. Detect
and clean up leaks before they hurt you
financially.

Because it's for the good of your commu-
nity and the environment. Petroleum
leaks can have serious .and far-reaching
consequences, such as the contamination
of soil, drinking water supplies, and air.
Petroleum and its resulting poisonous
vapors can also accumulate in nearby
confined spaces, such as septic tanks and
home basements, and can cause fires or
explosions. Communities across the
nation have suffered disasters resulting
from petroleum leaks. Don't let it happen
to yours.

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PAGB2
How Can This Brochure
Help Me?

If you own or operate an underground
storage tank that holds petroleum products
such as gasoline, diesel fuel, or oil, you
should know that there are detectors on the
market that can warn you about a leak. If
you choose an external leak detector, this
brochure will help you select the best one
for your underground storage tank. It
won't tell you which product to buy or
rank equipment from best to worst, but it
will give you the background you need on
external devices to ask the right questions
when you speak with vendors about their
products. You should also check with the
State or local agency responsible for
underground storage tanks in your area to
find out what rules apply to you. Qf you
are not sure which agency to contact, start
with your local fire department.)

This brochure will answer questions
about:

    • The purpose of external leak
      detectors;

    • Equipment and installation costs;
    • Compatibility with your current
      tank;
    • The types of detectors on the
      market;
    • How external leak detectors work;

    • The pros and cons of various
      types of equipment; and
    • What companies sell external
      leak detectors.
  What Companies Sell
  External Leak Detectors?
    '' "   •>       ''"'"
who t;0
                         to *
 . Protection Agency are Isted at the
  end of Msb>octee,,
  does not endorse any specific
  product or company, nor does ibis,
 vlist inciucte all 
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                                                                               PAGES
How Does an External Leak
Detection System Work?

An external leak detection system has two
main components: (1) the leak detector
itself, and (2) one or more monitoring
wells. External detectors range from
simple, hand-held devices to sophisticated
automatic equipment If a leak occurs,
petroleum liquid and vapor flow into
nearby monitoring wells near the tank,
where they are detected by the leak detec-
tion device. Some detectors use sensors
located inside the monitoring wells to
trigger an alarm in a central control panel;
others test samples of water or air taken
from the wells. (See Figure 1, below).
                Vapor
            •^-Monitoring
                in the Soil
                                                         Ground-Water
                                                         Monitoring Well
                 Figure 1. Underground Storage Tank System with Monitoring Wells

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PAGE 4
How Much Will It Cost?

External leak detectors range in price from
about $100 for a basic manual detector to
more than $14,000 for a high-end auto-
matic system. Detectors
that respond to petro-
leum vapors are usually
more expensive than
those that respond to
liquid.

Installation costs, which include the cost
of putting in the monitoring wells, vary
considerably. But maintenance is rela-
tively inexpensive for most models. By
doing some comparison shopping, you can
find an external leak detector that does the
job and fits your budget.
 How Do I Know I'm Getting a
 Good System?

 Although some external leak detectors
 have been used with petroleum under-
 ground storage tanks for a number of
 years, many are new or have been used for
 other purposes. The newer models may
 work as well as those used in the past, but
 you'll need to make an extra effort to
 ensure that you're getting the right system.
 That's why it's important to talk with
 several vendors and obtain as much infor-
 mation as possible about their products.
 Find out how long their equipment has
 been on the market and how it has been
 used in the past. You'll also want to check
 to make sure the equipment you purchase-
 meets State and local requirements.
Your leak detector should come with
detailed operating instructions and be
backed by a warranty. You should have
the detector checked every year by the
company that sold you the equipment to
ensure that it is working properly.
Can I Install the Leak Detector
Myself?

No, it takes someone with specific techni-
cal knowledge to install monitoring wells
and leak detection equipment. In addition,
some States require installer certification,
and others may do so in the future. Many
vendors install leak detectors and monitor-
ing wells themselves.  If not, they can
usually recommend an experienced con-
tractor to do the installation. Remember,
this is a lifetime investment that can save
you trouble and money in the future.
Don't try to cut corners on installation
and end up with a system that doesn't
do the job.


Do  I Need Special Training to
Operate the System?

If the company that sold you the equip-
ment offers a training class,, it would be
worthwhile to attend.  If not, ask the
company's representative to walk you
through the testing procedures, and see if
there is a' 'hotline'' number to call if you
have a problem. Be sure to read and
follow all instructions that come with the
detector whether you have a manual or
automatic device.

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                                                                               PAGE 5
Who Should Be Responsible
for the Leak Detector?

If you can't do it yourself, you should
depend on a person who will follow the
monitoring and testing procedures out-
lined in the instructions and record all
readings accurately. The benefit to you is
protection against ground water contami-
nation, which can be very costly to clean
up.
Can I Use an External Detector
with My Current Tank?

In most cases, the answer is yes. But you
have to consider two key factors: (1) the
type of backfill in the excavation zone
surrounding the tank (tank systems are
buried in an ' 'excavation zone,'' which
extends from 1 to 3 feet beyond the tank
on all sides), and (2) whether the soil
around the tank has been contaminated
by petroleum.

Backfill: Leak detectors work best when
a porous material such as pea gravel or
sand is used for backfill within the excava-
tion zone. Leaking liquids and vapors
flow rapidly through this type of soil to
monitoring wells.

Clay soils, which are not porous, should
not be used as backfill with an external
detection system, because clay will delay
leaking petroleum-particularly liquid
petroleum—from reaching monitoring
wells. However, an external detector can
 be used in an area with clay soil as long as
 a porous material is used as backfill. Most
 underground storage tanks installed in
 recent years have a pea gravel backfill, but
 many older tanks are surrounded by
 whatever type of soil happens to be at
 the site.

 The equipment installer should check the
 type of backfill and the level of existing
 contamination before installing your leak
 detector. You should check with the
 vendor or installer to make sure that these
 tests are performed and that the device you
 plan to buy will work under the conditions
 at your site.  Find out if your vendor has
 installed other leak detectors in your area
 and whether there have been any problems.

 Existing contamination: If you install a
 leak detector at your existing tank site, it
 must be able to detect any new leaks even
 though there may already be contamination
 from a prior leak or spill. External leak de-
 tectors work best when the soil and ground
 water near the tank are clean.
What Kind of Equipment
Do I Need?

There is a wide range of equipment to
choose from. In the survey of vendors, the
U.S. Environmental Protection Agency
identified nearly 50 companies that sell
external leak detectors, and many of them
offer several models. There are other com-
panies that sell external leak detectors that
were not covered by the survey.

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PAGE 6
External leak detectors come in two
categories-those triggered by liquid fuel
and those that react to vapor.
 In addition, some leak detectors are
"intermittent," which means you must
perform manual tests at regular intervals,
while others are "continuous"--they
operate automatically. Here are some
things to consider when deciding which
type will best suit your needs:
        Liquid vs.
Vapor
Liquid detectors: Liquid detectors work
best in areas where the ground water is
close to the surface, making the soil
around the tank wet Leaking fuel seeps
down through the soil to the ground water
and floats on the surface of the water as it
is carried to monitoring wells.  Liquid
detectors are suitable for use with most
petroleum products.

Vapor detectors: Vapor detectors work
best in places where the ground water is
deep and the soil around the tank is dry.
However, vapor detectors will work in
shallow ground water conditions if sensors
installed in the monitoring wells are not
actually under water.  Vapor detectors
react more quickly to leaks man liquid
detectors, because vapor spreads more
quickly than liquid. But vapor detectors
are highly sensitive and, therefore, more
likely to give false readings, and they may
require more maintenance than liquid
devices. Vapor detectors work best with
fuels that produce a large amount of
fumes, such as gasoline.
Manual vs. Automatic

There is no simple rule to help you decide
whether to use a manual leaik detector or
an automatic one. The decision depends
on a number of factors incMding your
financial resources, the soil around your
tank, the number of tanks and sites, and
the fuels being stored. Here are some
things to consider:

Manual detectors: Manual, detectors are
easier to use and less expensive than
automatic devices; but they require
monthly tests at all tank locations, and a
record must be kept of the results. Manual
detectors let you know immediately if
petroleum liquid or vapor is present in a
monitoring well, although iftey only work
when you are testing.

If you can take the time to do the tests and
keep accurate records of the results, a
manual system may be cost-effective.  If
not, you're probably better off with an
automatic system.

Automatic detectors: Automatic detectors
are usually more expensive: than hand
operated ones; but they cam be less time
consuming to operate, because you don't
have to perform routine tests as you do
with manual devices. Automatic detectors
are working all the time and will send a
warning signal if petroleum liquid or
vapor enters a monitoring well.  Some
devices send the signal within minutes
after petroleum is detected, others can take
as long as 20 minutes. Except for regular
maintenance, you don't have to spend
much time monitoring the system.

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                                                                                         PAGE7;
However, just as vapor detectors are more
likely to give false;readings than liquid
detectors, sophisljeMed;automatic devices
are more likely to r^fifujjction than sim- -,.
pier manual detectorsf: Ypu could think of
an automatic detector |s a race car that
needs to be kept in tjip|tpp lioridltiioia roF
peak performance, while a manual detec-
                     fci'
tor is more like the basic '•• , •>-'<."  X  •• 'v^^'l." -. I  f Mf, A
 '„ , V^ ->";:;'^<./   V^ ' '^?*. •r?-.^" \ t,."-s-'L '"l-|A.i.>^^iJll::'l!k*iXi. -CA^J;^ /^""i ^
                           f vanes ~v-
greatly depending up6n sbll and water-, ~
conditions and the location of the wells.
The more porous the soil around the tank
and the closer the monitoring Tyelts are to
the tank, thelnorefluicJdy leaking' " -*"
pefroleom wflt reach the well.
                     automatic leak  ,    ,
  ^etebtQrs^and-someipanufidevices/re^ct
  ,JO cheaiical$tvap6i5S, and other substances, '
 *  inihegto^uldorvairtiiatateu'nrelated't&! '  *
   your petrbleUrrt underground storage-tank, ,
   When i|iis occor^s it can cause the detector .-.
   to send a false warnm^ or rniss_a real tank:  ,'
   leak* _,^k j^our vendor wfiat interference|'
   mayaffect the lealk detecWyou plan to^"" '
   6uy and find Oiit what yb'ucaif do'aBout- -^
                                                         Hgure "$.' Details of 'a Manltoring Wiiil "
                                                        ^ 1U 05^7'. ii' cl 1;;anq i.5;;i5f|i; r?2m  DiilS^t
                                                   How Many Monitoring Wells Do
Naturally, the more you have the better
yourctiahces "of finding a Ibak^ ' WT^ai^r '
'  -,.: ' Vr--a./;-r«fS^ '*Tfl- ysrjj^jj,! ,ri' '--rt Vl*»-i/f , f i-5.*-. .-..,
the number of moni|6nng wells, hbwever,
you do not necessarily need rnore     '
aetector, you pan test
the5 same e^rpnifentj If ^cfei^vfe airi;"s'v a
automafic" detector, serisors in eaBh well
 ;sr;si«£.f0 afH^Ft^nof-^ n.^-'i ?;--Hi--v:' .!».'is'r*^rf-<
are connecfejq,:tp ja cpntral control panel.  "
Howe^Hr^yqu m^'h^^ ad^tional 10^!"
detectors ^oulh^^iy^^seyertr '°'"
locatiohsf figure; 2 aibove^ iilustrates 'tlte
     -'•f^t 3^-jJnJlt (n'fi"i"•:•••.?» .-:* «r.-.Tt -,-,•:»» ?^tt«.-•?•.
components of ia typical monitoring well.)

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PAGES
How Do External Leak
Detectors Work?

Here is a brief description of the main
types of external leak detectors and their
strengths and weaknesses:
Manual Liquid Detectors

The two most commonly used manual
liquid leak detectors are "grab samplers"
and chemical-sensitive pastes. In grab
sampling, a clear container with a valve on
one end-known as a bailer-is lowered
into a monitoring well and then removed.
If fuel is present, layers of petroleum will
be suspended in the water like an oil slick.
In the second method, a tape measure
treated with special paste is placed in a
monitoring well. If fuel is present, the
paste changes color. (See Figure 3,  next
 column.)

 Strengths: Manual liquid detectors are
 widely used because they are inexpensive,
 accurate, and easy to operate.

 Weaknesses: Manual liquid detectors
 provide limited information about the type
 of contamination found. (However,
 chemical analysis can identify the material
 collected by grab sampling.) They do not
 allow for continuous monitoring as do
 automatic devices; therefore, someone
 must take time to perform routine tests.
    Figure 3. Chemical-Sensitive! Pastes with
             Tape Measure
Automatic Liquid Detectors

There are three types of automatic liquid
detectors. Interface probes operate by
beaming light through a probe located in a
shaft near the tank. If there is liquid in the
shaft, the light beam is interrupted and a
signal goes off in the control panel;
another sensor determines whether the
liquid is water or petroleum. Another
type, known as a product soluble device,
has a cable or hose made of material that
dissolves in petroleum. The cable or hose

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                                                                                  PAGE 9
     Ground Laval   To Control Box
                            Probe Tips
                         (Adjustable Length)
     Figure 4. Thermal Conductivity Sensor
is suspended in a monitoring well, and if
petroleum is present, it will dissolve the
material and trigger an alarm. A third, the
thermal conductor, uses a sensor with a
heating element that floats in a monitoring
well. If petroleum is present, a change in
the rate of heat loss triggers an alarm.
(See Figure 4, above.)
Strengths: Some automatic liquid detec-
tors have been on the market for 15 years,
and thousands of them are in use. The
central control panels have a long service
life and can accommodate multiple sen-
sors. One type~the product soluble
device-detects both petroleum liquid and
vapor.
 Weaknesses: Interference by ultraviolet
 light, water vapor, ice, and other sub-
 stances can trigger false readings. The
 response time varies from one model to
 another.

 Manual Vapor Detectors

 There are at least six different categories
 of manual vapor detectors. The basic
 mechanism is that a sample of water or air
 from a monitoring well comes into contact
 with a flame, heating element, ultraviolet
 light, or other material within the detector.
 If petroleum is present, an electrical or
 chemical change occurs and can be seen
 by reading a meter or gauge.

 Strengths: Some manual vapor detectors
 have been commercially available for 10
 years, and many are currently in use,
 although not necessarily for petroleum
 underground storage tank leak detection.
 They are highly sensitive and respond
 within seconds.  Some models can identify
 the exact material that has been detected.
 Control panels have a long service life.

 Weaknesses: Manual vapor detectors
 require special maintenance, making them
 time consuming to operate. They are
 subject to interference, which can result in
 false readings. The central control panels
 usually support only one sensor; if you
 have more than one monitoring well, you
 will need additional devices.  However
 some devices are portable so you only
need one even if you have more than one
monitoring well.

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PAGB10
Automatic Vapor Detectors^  Ai-itiSKti
There; are three; main jtypes of jautomatic ,K-E
vapor detectors. . The flae^alroxjde. serni^ -•;
conductor works on the principle that;   ; ;.;
petroleum vapor will cause a change in the
electrical current ip acellinsid^jhe^ -^^ --_
detector. A variation on this model, called
an adsistor or diffusion sensor.ruses the , „ r
   •  or^; V, :'V"-^-:-- -"•— Jb™Si is ;^rt ;;ji-~"'
same principle butpperates somewhat ., J; -
          ' ''''
differently.'                           .  .
  •V, ••".  ;*Ji:, •  al 4--.KI-K 3 tatti c; HV.EnSjV.iiH
product permeable device, uses matenals  .A
V- '..tf-.v i •••.*.« 3ft.->jfvv ;-t-:* smvytno/n s moil
that allow vapor but not water to penetrate
   •• • .„•• •.•'-'•'•I  •^--."if-t* •"'Vl'1:S»f' -Affy^s a ryrw
into the detector. Once the vapor is inside,
 , -i. •„-  ..•-•.»,,•», .•.;-,•';: ..,- li-h--*'^ •pjm's'rf* J?!if!
the detector operates the same ,way as a_' ,.
metalM5xide'seriqaconductb£
the catalytic sensor, works 6y brmgtog5 an "'
air sample into coni&ct with Heated fiia-
ments.  If vapor is present, the temperature
inside the^detectdr-will nse"Sfd:triggeran" c
Strengths: Autdmatj^apoVdetectors1- ?> * ^
are new to the underground stofage lafik • ' "
market, but thousands of thes^devices ^f
have been used during the"pastdecade:J A ^ *
for Other applications. :Some models can: I
tell ypu:what type.ofjnaterial has;beeaj -,
detected. They are highly sensitive and
have a^apid response time.,: The cpnttol
panels have ia long service life and c.an^:-: -.
accommodate multiple senso|Si wMch4ast
from 1 to 10 years. -;.  ^,^-^swi or ryy^
   -•'--•-  •  -:i-,;.:)^Lr":~s? sriT .mrn'mm 321^
Weaknesses:, Automatic -y.appr detects, , .i:
are subje^t,tom^ere.n.QB-^mj!5rjd^ sv^
range of substances, which can;cause false.,
      * "* " • J-Y* " '-: i - (• ""h * j .'".'.:'/ .'^r-i .\«' I » li iX""> iiTMfWit il|i-l
readings.,' "1  _." _:,...„,.,„ ,-, . v^;,,t« .:,-,-r,
       ....'- ».-J\'O;' -ll:',,K;j-l,i..'*4 J.JAM ,»,„?.;;,! 'r-jjj./jti ;|.":
                          M 113^3 *ftv s^p
 • tion Agency does not endorse companies or
          lite vendor Jist&<0judted III fias ,
  itdoesnotincludealUptnipaniiJsthatseU
  external leak detectors.
How Can 1 Get More     >-jr
Information?            ^       -   r

A more detailed description of the devices
discussed in this brochure plus additional
informatioaon external leak detection are
available. You majTorder the U.S. Envi-
ronmental Protection Agency's complete
report, "Survey of Vendors of External
Pe^eum^ak.D^tection Devic|s,fpr,sl|set
witn^nder^iind Stprag4.Tan|s," |gM?JU;
the,$u^nnten4pnt pf^Dp^uEiienjt^.Gpy^^g,,
ernm|^f)^tm|.jQffic^, Washington, D£;i.
1116
                    ^       ,
For specific requirements that apply to
your tank, please call your State or local
agencylp contact, start, with ypjw local
      Oil It  ,*S!J i»J >>s-f> il.itiiij ,i^ trf^lSMKiJWl
                   ri aianaq l
For generai'infpjmatipn pnjhe natipnal  ,,
	   a.iij«sOs i~?UtHJ*'-i 'J'iv^zS-V.* —*-">>i* „' - "'
               ^Ott

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 Detector Type
 Company       Address
                        Phone
                Product
           Liquid  Sensors
MANUAL
Grab Samplers
 Chemical-Sensitive
 Paste
AUTOMATIC
Interface Probe
Monitor

Monitor
 NEPCCO
 Norton
 Chemplast

 (many others)

 Kolor Kut
 Products

 J.H.McCabe
 Co., Inc.
Comar, Inc.
29 Wall St
Foxboro, MA 02035

150 Dey Rd.
Wayne, NJ 07470
P.O. Box 5415
Houston, TX 77262

P.O. Box 822
Short Hills, NJ 07078
P.O. Box 832676
Richardson, TX 75083
617-543-8458   Liquid Samplers
               and Bailers

201-696-4700   Bailers
713-926-4780    Water & Gasoline
               Finding Pastes

201-635-0963    Water & Gasoline
               Indicator Pastes
214-238-7691    *Models 807,808,
               & 809 Tank Monitors
               *PLD-17 Pipeline
Gauging
                        EMTEK,Lic.
                27 Harvey Rd.
                Bedford, NH 03210
                       603-627-3131   Electronic Well
                                      Light (EWGL-12)
                        Marine Moisture  60 Inip Dr.
                        Control         Inwood, NY 11696
                                       718-327-3430    Sonic Ullage Interface
                                       800-645-7339    Probe
                        Groundwater     220 Norwood Park S.       617-769-7600    Interface Probe
                        Technology, Inc.  Norwood, MA 02062
Product Soluble
Devices
EMTEK,Inc.     27 Harvey Rd.
                Bedford, NH 03102

IFP Enterprise    680 Fifth Ave.
                New York, NY 10019
                        In-Situ, Inc.
                210 South 3rd St
                Laramie, WY 82070
                       603-627-3131    Detection
                                                              212-265-3800    Oil Fuse
                       307-742-8213    Petrochemical Release
                                      Monitors
                       K&E Associates   3312 Industry Dr.         213-424-1517   PMS-800
                                       Long Beach, CA 90806

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Detector Type
Company
Address
                                                               Phone
                                                      Product
Product Soluble
Devices (Cent.)
Electrical
Resistivity
Sensors
 Thermal
 Conductivity
 Devices
Pump Engineer   921 National Ave.
Associates       Addison, EL 60101
Technology
2000, Inc.

Control
Devices
                        Total
                        Containment

                        FCI
                         Leak-X
                                       265 Ballardvale St.
                                       Wilmington, MA 01887
                       312-543-2214   Sentinel


                       617-658-2900   TOLTECH Hydrocarbon
                                      Monitor
2009-A West Detroit St    918-251-0387   Wik-Stik
Broken Arrow, OK 74012
                15 E. Uwchlan Ave.
                Exton,PA  19341
                                                               215-524-9274
                                      Total Containment
                                      Cable-TC3000
                1755 LaCosta Meadows Dr. 800-854-1993   785 Leak Detection
                San Marcos, CA 92069    615-744-6950   Systems
                560 Sylvan Ave.          201-569-8989   Leak-X Syslem
                Englewood Cliff, NJ 07632
 Pollulert Systems
 (Mallory)
 Groundwater     220 Norwood Park S.
 Technology, Inc.  Norwood, MA 02062

                P.O. Box 706
                Indianapolis, IN 46206
                        617-769-7600    CMS Variable
                                       Level System

                        800-343-2126   FD102and
                                       FD103
                        Universal Sensors 9205 Alabama Ave, Unit C 818-998-7121    Leak Alert System
                        and Devices, Inc.  Chatsworth, CA 91311
           Vapor Sensors
 MANUAL
 Detector Tubes
 Combustible Gas
 Detectors
  MSA
 National
 Draeger, Inc.

 MSA
 10770 Moss Ridge Road   800-672-2222    Samplair Pimp &
 Houston, TX 77043        713-690-6268    Test Kit
 P.O. Box 120
 Pittsburgh, PA 15230

 P.O. Box 426
 Pittsburgh, PA 15230
                                                               412-787-8383
800-672-2222
412-967-3000
Gas & Vapor
Detection Products

Several models

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aK388838S83SS88£3£SB«!SSS8KS?l
Detector Type
Photoionization
Detectors



Portable GCs





FIDs
Infrared

AUTOMATIC
Catalytic Sensor
Devices
Company
AID, Inc.
Astro Int
Corp.
HNU
Photovac
International
AID, Inc.
HNU
Microsensor
Technology Lie.
Photovac, Inc.
Sentex Sensing
Tech., Inc.
XONTech
Foxboro
Analytical
Foxboro
Analytical
Horiba
Instrumental
Bacharach
Instrument Co.
Address
Rt 41 & Newark Rd.
Avondale, PA 19311
100 Park Ave.
League City, TX 77573
160 Charlemont St
Newton Highlands, MA 02161
741 Park Ave.
Huntington, NY 11743
Rt. 41 & Newark Rd.
Avondale, PA 19311
160 Charlemont St
Newton Highlands, MA 02161
41762 Christy St
Fremont, CA 94538
739BParkAve.
Long Island, NY 11743
553 Broad Ave.
Ridgefield,NJ 07657
6862 Hayvenhurst Ave.
VanNuys,CA91406
330 Neponset Ave.
Foxboro, MA 02035
330 Neponset Ave.
Foxboro, MA 02035
121 Duryea Ave.
Irvine, CA 92714
625 Alpha Dr.
Pittsburgh, PA 15238
Phone
215-268-3181
713-332-2484
617-964-6690
516-351-5809
215-268-3181
617-964-6690
415-490-0900
516-351-5809
201-945-3694
818-787-7380
617-543-8750
617-543-8750
800-446-7422
412-963-2235
Product
Model 580
Trace Gas
Analyzer-1010
Model PI 101
TIP
*Underground Tank
Monitor
Model 590
Models 201.301D,
501
Michromonitor
Photovac 10A10
Scentor
GC-810
Century OVA
Miran
IR Hydrocarbon
Gas Analyzer
*TLV Sniffer
*Model303
Gaspointer
Gas Tech, Inc.
8445 Central Ave.
Newark, CA 94560
                                                                                *ModelH
415-794-6200   Model 1238

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Detector Type
Company      Address
                                                                 Phone
                                                        Product
Catalytic Sensor
Devices (Cont.)
 Metal Oxide
 Semiconductors
Industrial
Scientific
Devices Corp.

Intek Corp.
                         Lumidor
                         Safety Products

                         Detector
                         Electronics
API/Ronan
                         Armstrong
                         Monitoring
                         Azonic
                         Technology Corp.

                         Calibrated
                         Instrument, Inc.

                         EnmetCorp.
                         Genelco, Inc.
                          Harco
                          Technologies
                          Corp.

                          International
                          Sensor
                          Technology

                          MSA
                          Groundwater
                          Technology, Inc.
355 Steubenvffle Pike
Oakdale, PA 15071
P.O. Box 42821/606
Houston, TX 77042

5364 NW 167th St.
Miami, Florida 33014

207 East Java Dr.
P.O. Box 3566
Sunnyvale, CA 94088

12410 Benedict Ave.
Downey, CA 90242

2l5Col6HadeRd.S.
Nepean, Ontario
Canada K2E7K3

1671 Mabury Rd.
San Jose, CA 95133

731 Saw Mill River Rd.
Aidsley, NY 10502

2308 S. Industrial Hwy.
 Ann Arbor, MI 48104

 11649 Chairman Dr.
Dallas, TX 75243

 1216 E. Tower Rd.
 Schaumberg, IL 60195
                 17771 Fitch St
                 Irvine, CA 92714
                 600 Penn Center Blvd.
                 Pittsburgh, PA 15235

                 220 Norwood ParkS.
                 Norwood, MA 02062
                                                                 412-788-4353    LD-222
                                                                 713-498-5855   IGD
                                                                 305-625-6511    Model CRP-1
                                        408-734-1221    Combustible Gas
                                                        Detection System
                                                                 213-803-1497   TRS76
                                                                 613-225-9531    4200 Sensor
                                                                 408-729-4900    Enviro-Ranger
                                         914-693-9232    Pure Air Monitor
                                          313-761T1270   Several models
                                         214-341-8410    Soil Sentry
                                                                  312-882-3777    Multi Ram 12
                         714-863-9999   AG5000 & AG5100
                         412-776-8802   Tankgard
                          617-769-7600    Vapcir CMS
 Metal Oxide
                          Sierra Monitor ,   1991 Tarob Court
                                          Milpitas.CA 95035
                          Universal        9205 Alabama Ave.
                                         408-262-6611    Model 201

                                         818-998-7121    Leak Alert

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Detector Type
Company
 Address
Phone
Product
Semiconductors
(Cont.)
Product
Permeable
Devices
Sensors and
Devices, Inc.

U.S. Industrial
Products Co.

Teledyne
Geotech
UnitC
 Chatsworth, CA 91311

13564 Pumice St
Norwalk,CA 90650

3401ShilohRd.
 Garland, TX 75041
                                                                 213-921-4342    Tank Monitor
 214-271-2561    LASP System
Diffusion
Sensors
                        W.L. Gore
Adsistor
Technology
1505 N. 4th St
Flagstaff, AZ 86002

11300 N.E. 25th St.
P.O. Box 98115
Seattle, WA 98125
                        EmcoWheaton    Chamberlain Rd.
                                         Conneaut, OH 44030
                        EMMCO, Lie.
                2525LehighPl.
                Costa Mesa, C A 92626
                                                                 602-526-1290   LEAKLEARN
206-523-6468    Adsistor Sensor
                        216-599-8151    Leak Sensor E
                                        Vapor Probe

                        714-545-6030    Env. Control Safety
                                        Monitoring System
                        Spearhead
                        Tech., Inc.
                P.O. Box 51160
                Seattle, WA 98115
                        604-688-8245    STI2X12 Inground
                                        Tank Monitor
                              *U.S. GOVERNMENT PRINTING OFFICE: 1990-0-720-137

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