PIDs As HazMat Response Tools

Technical Note TN-163
rev 5 ab.05-07
cleaner from a department store can be used. To
clean the sensor, remove it from the instrument
and
immerse it in lamp-cleaning solution (anhydrous
methanol) in a small beaker or baby food jar. Fill the
ultrasonic cleaning bath with water. Place the beaker
containing the sensor into the water bath of the
ultrasonic cleaner. The ultrasonic waves pass through
the water and container and assist in cleaning the
sensor. The lamp-cleaning solution in the jar can be
reused a few times until it becomes dirty. Remove the
through the tube easily. Some heavy vapors such as
diesel fuel or polar compounds such as acetone and
alcohols require extended sampling times. See
Technical Note TN-178 for more details and cautions
on use. (Note that Type I Humidity Filtering tubes
cannot be used during measurements.)
Flex-I-Probe
Tube Tip Breaker
(p/n 021-2400-100)
Tube Adapter
(p/n 025-3002-000)
Humidity Filtering II Tube
(10-pack, p/n 025-2002-010)
Water Bath
Methanol
in Jar
Ultrasonic Cleaner
sensor and allow it to dry for at least a few hours, and
preferably overnight (warm but not hot air will speed
the drying process).
Caution! Do not overheat the sensor, and never
disassemble the sensor!
It is very important to blow or shake out any residual
lamp-cleaning solution from the sensor before letting it
air dry. Otherwise, some of the dirt that was just
extracted into the cleaning solvent could be deposited
back onto the sensor components as they dry.
Reinstall the clean, dry sensor into the MiniRAE 2000.
Exhale into the instrument and check the response. If it
shows no response to the moisture in your breath,
calibrate the instrument and return it to service.
Using Humidity Filtering II tubes
Humidity Filtering Tubes (Type II) can be used to dry
the sample gas and measure many VOCs for about 15
minutes to 1 hour. Their use prevents moisture effects,
even on a dirty sensor. The tubes (p/n 025-2002-010)
are inserted into an adapter (PN 025-3002-000) attached
to a Flex-I-Probe (PN 021-2400-000). Many
compounds such as trichloroethylene and gasoline pass
MultiRAE Plus and EntryRAE
While the MultiRAE and EntryRAE do not normally
have as many issues with dirt in PID sensor,
contamination is possible. The moisture test is done
by cupping your hand over the end or breathing
gently into the end, being careful not to block the air
flow. If the VOC reading increases over 5 ppm
isobutylene, there is a problem with dirt.
Filters
The MultiRAE uses a smaller external filter (PN 008-
3022-001 for a pack of 3, PN 008-3022-010 for a
pack of 10, PN 008-3022-100 for a pack of 100, and
PN 008-3014-000 for a single external filter with
adapter for the silver MultiRAE). This white filter
should be replaced when it is dirty and when the
instrument responds to moisture. If the instrument
goes into pump alarm with the filter attached and is
able to run without any problems when it is not
attached, it is time to replace the filter.
The EntryRAE uses a small external filter (PN 490-
0122-000), which should be replaced when it appears
dirty or when the instrument goes into pump alarm
with the filter attached and clears the pump alarm
when the filter is removed.
MultiRAE PLUS
There are two versions of the MultiRAE Plus, silver
housing and black housing. There are small differences
when cleaning them. If there is a response to moisture,
dirt has gotten to the lamp. Due to the gas flow within
the instrument, if dirt has gotten to the lamp, it has
probably gotten into the filter, pump, tubing (silver
MultiRAE only) and the gas plate.
4
RAE Systems Inc.
3775 N. First St., San Jose, CA 95134-1708 USA
Phone: +1.888.723.8823
Email: raesales@raesystems.com
Web Site: www.raesystems.com