Maintenance Instructions for Prometheus Humidor, Optima and SCS
1. Storage of Cigars
Your cigars will taste best if they are kept in the
environment which provides Relative Humidity range
of 68 - 70% and temperature range of 68 - 70 degrees
Fahrenheit (20 - 21 degrees Celsius). If your cigars go
through harsh temperature and humidity variations,
they will lose their flavor. Prometheus humidors
equipped with a Prometheus Optima humidifier
provide an optimally controlled environment (Relative
Humidity of 68% - 70%) for your priceless cigars.
2. Relative Humidity
The Relative Humidity (RH) is defined as the amount
of moisture in the atmosphere in comparison with
that at the saturation point at a given temperature.
Water exposed to air gradually evaporates until the
saturation point at which the air may retain the
highest quantity of evaporated water. At the
saturation point, the slightest drop in temperature will
cause condensation. This is known as the dew point
and corresponds to 100% RH. At 20 degrees Celsius
(68 degrees Fahrenheit) and a normal atmospheric
pressure, the amount of water present in the air at
100% RH is approximately 15 grams per cubic meter.
At a Relative Humidity of 70%, the amount of
evaporated water is approximately 10.5 grams per
3. Why Create a Humid Environment with a Constant Relative Humidity of 68% - 70%?
In common with many organic substances, cigars
dry out in the absence of humidity in the air, or
absorb moisture when air humidity is high. They
establish equilibrium with the surrounding humidity.
A dry cigar burns too quickly. The temperature at
which burning occurs is too high because it is not
tempered by the natural moisture of the cigar. The
smoke is hot and bitter, and the cigar becomes
harsh. In contrast, a damp cigar does not burn
easily. It becomes difficult to draw.
For a pleasant smoke, a cigar should contain a
certain amount of moisture which corresponds to 13
- 14% of its total weight. When this is the moisture
content, the cigars burn smoothly; and the draw is
easy. The aroma of tobacco is fully developed while
the irritating effect of the smoke is moderated by the
humidity of the cigar itself. The ideal moisture
content of a cigar (13 - 14%) corresponds to a
Relative Humidity of 70%.
4. How to Create and Maintain a Constant Relative Humidity of 68% - 70%?
If you place a water reservoir inside the humidor, the
water will evaporate right away. As a result, the air
inside of the humidor becomes quickly saturated by
evaporated water and the humidity inside of the
humidor will shoot up in a short period of time.
However, as you open and close the humidor, the
humidity inside the humidor will disappear rapidly.
This means that your cigars will dry up shortly after all
water in the reservoir has completely evaporated.
In the above environment, your cigars will go through
sudden humidity change. Many humidors come
with a humidifier containing a foam, which soaks up
water and lets its water evaporate rapidly just like the
above water reservoir example.
Prometheus Optima humidifier comes pretreated
with 1) a special chemical mixture including
propylene glycol; and 2) distilled water. This special
chemical mixture controls the evaporation of distilled
water. The Prometheus Optima humidifier lets its
water evaporate when the Relative Humidity falls
below 68% - 70%.
Prometheus Optima humidifier, which is
pretreated at our factory in France, comes sealed
to preserve its pretreatment. Please do not break
its seal until you are ready to use it. Once you
open the seal, you just have to fill it with distilled water
and your Prometheus Optima humidifier is ready to
Also, a Special Care Solution has been developed by
our laboratory to ensure proper performance of the
Prometheus Optima humidifier. This solution
regenerates the special chemical mixture.
We advise you to treat your Prometheus Optima
humidifier with our Special Care Solution
(Prometheus SCS) once every six months so that your
Prometheus Optima will continuously deliver
controlled evaporation of distilled water. You can
purchase Prometheus SCS at premium tobacco
5. Prometheus Optima and How to Maintain Proper Humidity inside Humidor?
By adding distilled water to the Prometheus Optima
humidifier periodically, you can maintain the Relative
Humidity of 68% - 70%. Under normal use, your
Prometheus Optima humidifier should be refilled with
distilled water approximately once every month.
Make sure to use distilled water only so that no
bacteria will develop inside your humidor.
When you set up your Prometheus humidor for the
first time, you might have to refill your Prometheus
Optima humidifier more than once a month
because the inside veneer of a new humidor is quite
dry. In addition, you might want to wet a paper or
cotton towel with distilled water and gently press it
against the inside surface of your new Prometheus
humidor. Do not rub the wet paper or cotton towel
harshly against the inside surface. This will damage
the inside veneer of your Prometheus humidor.
In setting up your new humidor, do not shock your
new humidor by overhumidifying it in order to get
the humidity level up quickly. This might damage
your humidor and the lid might warp. It usually
takes about a week to achieve the ideal humidity
level in your new humidor.
The hygrometer will enable you to determine whether
you need to refill your humidifier.
Many years ago, the old models of Prometheus
humidors came with an analog hygrometer (the kind
with a needle and a dial). The analog hygrometer
does not accurately measure the humidity level.
Consequently, starting in 2001, Prometheus has
begun offering its humidors with a complementary
digital hygrometer/thermometer whose
measurement of humidity is more accurate.
You can purchase a Prometheus digital
hygrometer/thermometer at premium tobacco
shops near you or contact us.
The instruction on how to use the Prometheus digital
hygrometer/thermometer is enclosed inside the
packaging box, or visit our website: www.prometheuskkp.com
Please note that digital hygrometers have a
margin of error of +/-3%. The best way to
determine how well cigars are humidified inside
the humidor is to monitor your cigars regularly,
and feel and smoke them.
7. Tobacco Beetles
When the humidity inside of your humidor falls below
the ideal Relative Humidity range of 68% - 70%,please
refill Prometheus Optima humidifier with distilled
water (about once a month).
During the humid summertime, the humidity inside
your humidor can go up significantly. If the humidity
goes higher than 70%, leave the humidor lid open
until the inside humidity goes down.
In addition, please make sure that your humidor is
kept in the temperature range of 68 - 70 degrees
Fahrenheit (20 - 21 degrees Celsius).
During the winter months, do not put your
Prometheus humidor next to a heater. During the
summer months, try to keep your Prometheus
humidor in an air-conditioned room which maintains
a temperature range of 68°F - 70°F (20°C - 21°C).
If the humidity and temperature of your humidor
move above the ideal range (68% - 70% and 68°F -
70°F), tobacco beetles, which exist in larvae form
inside of tobacco leaves, can hatch. If the outbreak
of tobacco beetles occurs, you will find your cigars
with circular pinholes. This is the evidence of
tobacco beetle infestation. In two days, the fullfledged
beetle infestation can destroy every cigar in
In the first place, you must prevent the inside
environment of your humidors from getting too moist
or too hot by keeping it in the ideal range (68% - 70%
and 20°C - 21°C).
If beetle infestation occurs, discard all of your cigars
with the circular pinholes and put the ones without
the pinholes in a sealed plastic bag. Then place
them in the freezer for 72 hours in order to kill the
tobacco beetles and their larvae.
After 72 hours, move the cigars to the refrigerator for
one day, and then back to your humidor. This extra
step will protect your cigars from the shock of sudden
Before you put the cigars back in your humidor,
clean the inside of your humidor with a paper or
cotton towel dampened with distilled water.
8. Mahogany or Spanish Cedar
The inside veneer of Prometheus humidor is
mahogany. Some humidors come lined with Spanish
cedar. We have chosen mahogany because it will
not affect the flavor of your cigars, whereas Spanish
cedar will give your cigars a cedar taste and aroma.
Also, Spanish cedar can bleed sap but mahogany
9. Cleaning of Prometheus Humidor
To clean the inside of your humidor,wet a clean cotton
or paper towel with distilled water and gently wipe the
inside of the humidor. If you would like to remove
fingerprints or stains on the inside mahogany veneer,
use fine grit and paper and gently rub it sideways
along the grain of the veneer but not against.
If you own a Prometheus humidor with glossy
finish, we recommend you to clean the outer
surface with rubbing alcohol. If your Prometheus
humidor has a satin finish, use a clean cotton
towel and gently wipe the outer surface. You must
not use rubbing alcohol or any cleaning solution
in cleaning the satin finished humidors.
WARNING: Warping of Your Humidor Lid
Prometheus stands behind its humidors and if a Prometheus humidor has any manufacturing defect, Prometheus will repair it at no charge according to its warranty. However, if the lid of the humidor warps due to improper maintenance by its dealers or consumers, the warped lid will not be covered by Prometheus Humidor Warranty. In order to prevent the lid of the humidor from warping, do not place the humidor under direct sunlight or track/spot lighting. Moreover, if your humidor experiences dramatic temperature changes, the lid of the humidor will also warp. During the winter months, you must not keep your humidor next to heater and during the summer months, prevent your humidor from being exposed to extreme sunlight.