Anaerobic Chamber FAQ

The amount of gas used depends on how often the chamber is in use. A chamber that is used minimally requires 150psi/day. A chamber that is used more heavily will use about 300 PSI per day from the tank.  The passbox is the largest consumer of gas on the chamber, so to save gas try to bring in smaller items through the sleeves and bring larger items in through the passbox.

If you feel the chamber is using an excessive amount of gas, the best way to check is to time how long the chamber sits between adding gas while sealed and not in use. Seal up the chamber and wait until you hear the gas click on momentarily. Start a timer and time how long it takes for the chamber gas to click on again. If the gassing interval is longer than 5 minutes then the chamber is not leaking and is sealed. Any excessive gas usage would be caused by passbox cycles or chamber use. If the gassing interval is under 5 minutes inspect the sleeves or other areas for leaks. You can use an electronic gas leak detector (sometimes supplied with new chambers) to quickly pinpoint the source of any leak.

We recommend a 3-gas mixture of anaerobic gas containing:

90% N2, 5% CO2, and 5% H2

DO NOT EXCEED 5% H2 IN THE CHAMBER DUE TO RISK OF EXPLOSION!

You do not need to use high purity gas, just the standard gas mixture with those ratios are acceptable. The CO2 content of the gas can be changed up or down depending on your preference.

We recommend the Oxoid indicator strip, BR0055, which is available commercially through Fisher Scientific. Alternately, an oxygen meter can be used as long as it is compatible with H2 and CO2. Note that this strip is very sensitive to O2 levels, &will turn a light pink at 100 parts per million oxygen.

When using and observing the strips, it is important that they only be opened after the chamber has not been in use for several hours, such as first thing in the morning. Open the strip inside the chamber, before bringing in anything through the airlock/passbox (the airlock will bring a small amount of O2 into the chamber). Let the strip sit in the chamber for a few minutes and make sure it stays white.

During normal operation of the chamber throughout the day, it is normal for the strip to turn a light pink. That is because bringing supplies into the chamber and going in/out of the chamber will always bring in small amounts of oxygen. The catalyst will scrub the oxygen out, but it takes some time to do it. When the chamber is continually being used, new oxygen will get introduced to the chamber as the catalyst is removing it, causing the strip to remain a light pink.

As long as the strip is white, and stays white for several minutes when opened first thing in the morning (or on first use of the chamber for the day) then you don’t need to worry about your strip turning light pink during chamber use.

Yes, butyl cuffs are available in Small, Medium, Large, and Extra Large. Call 1-800-443-3108 to order.   When ordering, make sure to specify the proper size.

• Open the incubator doors so that there is a 1/2” gap on either side of the incubator.
•  Close the passbox doors.
• Plug the sleeves.
• Remove one of the screws on the front window. We recommend one on the right side in the middle of the window. This will create a small leak of gas out of the chamber, and fresh new gas will be added every ~5 seconds.
• Allow the chamber to purge slowly until it has consumed 50 psi from the gas tank.
• Place an anaerobic indicator strip inside the chamber every hour to check the oxygen level. Let the strip set for 5 minutes and check the color. If it is white or very light pink then it is safe to work in again. The strip will
• When the chamber is anaerobic, remove the object from the cuff.
• Close the incubator doors.

The AS-580 Anaerobic Chamber catalyst should not require maintenance for at least one year. If the anaerobic indicator strip becomes solid/dark pink, purge the chamber. If it remains pink or becomes pink often, call 1-800-443-3108 for assistance. The strip should be pure white first thing in the morning or when opened after the chamber has not been used for 2+ hours.

Heavy operation of the chamber causes the anaerobic indicator strip to change to a very light pink and this is normal. Expect changes when frequently entering and exiting the chamber, during frequent introductions of supplies and immediately after passbox cycles. If the catalyst is functioning, it will scrub out small amounts of oxygen within a few hours.

When ordering a new replacement catalyst we offer two options: either a refurbished catalyst or a new catalyst. Both new and refurbished catalysts contain brand new, never used palladium catalyst pellets. The refurbished catalyst re-uses the stainless steel pipe and catalyst heater from a previously used catalyst that was sent back to Anaerobe Systems. The new catalyst uses new pipe and heater.

B900306N is the part number for the new catalyst. B900306R is the part number for the refurbished catalyst.

Anatox is an activated carbon charcoal which removes some of the hydrogen sulfide and volatile organic acids which are by-products of bacterial growth. This helps to reduce the foul odor and also helps the catalyst remain active. The reason for regenerating and eventually replacing the catalyst is that hydrogen sulfide bonds to the palladium on the catalyst and deactivates it.

We recommend placing a small stainless-steel bowl or container with 1/3 cup (100 ml) anatox inside the chamber incubator. If there is not room in the incubator, place it on the floor of the chamber. The anatox will eventually become saturated and no longer help in scrubbing out volatile compounds. There are two options for replacing or regenerating the anatox:

Option 1: Baking in Oven to Regenerate

• Every 1-2 days, remove the container of anatox and bake for a minimum of 6 hours at a minimum of 160ºC. We recommend using two containers so while one is being used in the chamber, the other can be baking to regenerate. After 1 month of use and regeneration, discard the anatox and replace with fresh anatox.

Option 2: Throw Away & Replenish

• Leave a container of anatox in the chamber for 1 week. After 1 week discard the used anatox and replace with fresh anatox.

Call 1-800-443-3108 and refer to item number B480012 to order.

This depends on how often the chamber is used per day. With heavy, daily use, the cuffs should be replaced monthly. Sleeves only need to be replaced when they are worn or damaged. With proper care, they can last several years.  You should always have several pairs of cuffs on hand in case of an accidental tear.  It is also advised to keep a spare set of sleeves on hand.  Sleeve tears (small ones) can be patched using black electrical tape.

When the incubator is not humid enough, the moisture will leave the plates and condense on the lids.

Always keep a beaker of water inside the incubator to maintain a humid environment and prevent plates from drying out.

• Avoid bubbling excess gas out through the manometer (except when first entering the chamber). If you are going to reach deeper into the chamber where it might cause gas to bubble out, reach with one arm while pulling the other arm out to maintain the gas inside the chamber.
• Always make sure the manometer is filled with 2-3 inches of water. When the manometer is too low, any small movements while in the chamber will push gas to bubble out of the manometer.
• Minimize passbox cycles by making sure all supplies are brought inside in bulk. You can also minimize the cycles by bringing in smaller sized items like small numbers of tubes or plates through the sleeves. You do not have to worry about letting in oxygen in through the sleeves while you put plates or tubes in. The chamber’s positive pressure inside will vent the anaerobic gas out through the sleeves, preventing oxygen from getting in.