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GrowFAQ : Security

How can I minimize my heat signature?

Added by:
snoofer  Last edited by:
~shabang~  Viewed: 21 times

Rated by 8 users:
9.25/10

Contributed by: snoofer

Infrared cameras are widely used by
law enforcement for border patrol, grow room
confirmation, and other surveillance operations. The
courts approved the use of this technology as it is
considered non-invasive.

Growers fear IR because
it’s difficult to ‘hide’ invisible heat. Protecting
yourself against excessive heat emissions is a good
defensive measure. This FAQ focuses on masking heat
emissions.

What is infrared?
Light
and heat energy warm objects, which then re-radiate
excess energy. Some of this excess energy is emitted as
low-energy infrared. IR is invisible to the naked eye,
but can be displayed and measured by specialized
cameras.

What does Leo look for?
Officers are trained to look
for hot spots on walls and windows, unusually warm
foundations, exhaust emissions from vents and chimneys,
and warming trends typical of marijuana grow operations.
Leo will wait until evening or early morning (when the
grow is up to full temperature and the air is cool). He
will also look for light leaks, smells and other info at
this time.

Note: Leo will try to image a
suspected grow-op from all angles, but is only legally
able to do so from public property (ie. Sidewalks,
roads, public paths, etc).

Note: power companies
occasionally image power pole transformers to see if
they are abnormally hot (problems), and to source power
theft.

Legal implications

(ExpensiveCloset) "A thermal imaging scan does not
intrude in any way into the privacy and sanctity of a
home…the privacy associated with a home, are (not)
threatened by thermal imagery." (US supreme court
ruling)

"The Supreme Court ruled 5 to 4 on June
11 [2001] that police cannot use infrared heat-detecting
technology to gather evidence from a private home
without a search warrant" High Times, October 2001
(Pg.20)

In Canada, IR is used in the
pre-investigation phase. Positive results can then be
used to obtain a search warrant.

Will
Insulation help?
Conventional insulation will
help block IR, but it is probably not enough by itself.
A fully insulated wall (R 40) will hold heat much longer
than a window (R 2). Concrete is a good conductor of
heat; after hours of HID lighting, foundations will
become abnormally warm.

Most growers flower at
night to take advantage of the naturally cooler air;
unfortunately, a warm grow house will radiate lots of
thermal energy compared to the cool night air.

How do I mask my heat emissions?

Note: Small grows (under 2000w) would probably not
emit enough heat to warrant the effort or expense.

Note: Reducing grow room temperature will reduce
heat emissions; however, the grow room will still be
warmer than surrounding basement rooms.

This
technique creates a false wall to contain cold air.
Interlocking rigid foam panels prevent hot grow room air
from contacting and warming house walls. Cold air is
blown into the gap between the foam and the walls for
maximum protection. The wall’s exterior will appear
‘cold’ to an IR camera, indicating a negative for
internal heat.

· "Partial room" (insulate
exposed walls only)
· "Room in a room" (entire rooms
are insulated)

*Floor. Concrete foundations
absorb heat readily. Build a sub floor to raise the
entire grow off the floor.

*Walls. Use
interlocking 1.5 or 2” foam insulation along all exposed
walls. Place the insulation 1-4” away from walls, fit
foam panels from floor to ceiling (some cutting may be
required), and blow cold air into the gap. Seal seams
and corners with tape. Cover walls with Mylar to reflect
heat back into the room.

*Windows. Windows are
essentially uninsulated, so you must fill the gap with
insulation. Draw the curtains/blinds, add black poly
behind, then add insulation.

Drawing
description
A – Public property that Leo
can image from

B – Internal basement room. Grow
room heat will still be noticeable, and this side needs
protection.

C -- ‘Safe’ basement rooms. Put
ballasts and reservoir outside to minimize heat

D – Partially insulated growroom. The pink band
is the interlocking foam insulation, the blue band is
the cold air contained between the insulation and the
house walls. The window on the bottom of the picture can
be open to allow cold air to enter the air gap. Room
temperature air can also be blown in from an adjacent
basement room through a hole in the foam panels.

Hiding the Exhaust
Safely
exhausting hot air is difficult; Leo looks for unusual
heat emissions coming from opened windows, chimneys,
dryer vents and other handy places. Note: running
exhaust to outside sheds, barns and tree stumps is well
known to Leo.

Exhaust down the sewer
Every house has a sewer vent
standpipe. By venting down the sewer, the exhaust will
be chilled and smell is distributed amongst you and your
neighbors. The sewer cleanout access is often a 3-way 4”
abs “T” with a threaded cap somewhere in the basement.
Remove cap, and hook your blower to the T (A 4” to 3”
adapter funnel may be required) and run blower 24/7.
This will not affect normal use of the sewer

Cool exhaust with water
Place a wet
towel (wicking water from a tray underneath) partially
over the end of the exhaust. Spraying water inside the
exhaust pipe works as well.

Underground
exhaust
Running the exhaust through a long,
buried pipe helps to cool the air. Perimeter drains can
be used for this.

Tools for the grower:

Note: most “night vision” devices use UV
(ultraviolet) and not longwave IR detection.

Engine heat “guns”. +/- 1F. Numerical readout,
laser pointer.
"Night Vision" scopes, cameras and
camcorders.
Infrared film (Kodak High Speed Infrared
Film 2481)

Links:
Legal:
Consumer IR engine guns:
Infrared film usage:

Last modified: 17:55 - Sep 18,
2002

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