The RAD7 radon monitor works most effectively when the incoming air sample has a low relative humidity. The DURRIDGE DRYSTIK Model ADS-3 transfers moisture from the incoming air to the air being pumped out of the RAD7. As the air enters a drying unit (not included) on its way to the RAD7, it will have already lost most of its moisture, greatly extending the life of the desiccant in the drying unit. In certain cases the need for desiccant is eliminated altogether.

The DRYSTIK has at its heart a Nafion humidity exchanger with diaphragm pump, fixed and variable flow limiters, and a programmable Duty Cycle Controller. These are all contained in a compact enclosure. The DRYSTIK’s pump compresses the sample air inside the membrane tubing, initiating the transfer of water molecules to the outer purge flow, drying the incoming air as it moves through the device.

The DRYSTIK is available in two enclosures: a standard case which is suitable for laboratory use, and a ruggedized Pelican case which is ideal for demanding field work. Each is available with three different lengths of Nafion tubing, providing differing rates of humidity reduction. The premium 144-ADS-3 and 144-ADS-3R models are capable of bringing the relative humidity of air flowing at 0.15 L/min down below 10% in less than four hours when operating with a 40% duty cycle, and the humidity can be maintained below 6% indefinitely without any desiccant. This allows a RAD7 to operate under optimum conditions with the highest sensitivity and lowest operating cost. At a higher flow rate of 1.2 L/min, the DRYSTIK can bring the RH down below 12%, which is sufficient for enhanced-sensitivity thoron measurement.

For soil gas measurement, the DRYSTIK provides high flow capability for thoron detection. For radon, the ability to lower the flow with the built-in Duty Cycle Controller means that continuous soil gas readings may be made indefinitely, without any risk of fresh air diluting the soil gas sample by diffusing down to the extraction point.

Principle of Operation

The DRYSTIK operates on a principle involving two tubes, one inside the other. The inner tube is made of NAFION, a Teflon based material that permits the movement of water molecules, while blocking air and radon. The air sample flows along the inner tube on its way to a drying unit, while the space around the inner tube is purged with dry air coming from the outlet of the RAD7.

Summary of Benefits

The DRYSTIK enables users to enjoy the full capabilities provided by the superior RAD7 technology, with its rapid response and recovery, vanishingly small background, thoron specific sniffing, and radon-in-water accessories, with the need to replace and/or regenerate the desiccant only after a long period. The cost of replacing used desiccant becomes insignificant.

With a pump upstream and a needle valve downstream of the NAFION tube, compressing the air inside the tube, the DRYSTIK works regeneratively, and can even eliminate the need for desiccant altogether.

DRYSTIK Performance
DRYSTIK Model* Initial Humidity Humidity after 300 min.**
ADS-3-12 32% 17%
ADS-3-48 34% 10%
ADS-3-144 48% 7%
*Applies to both ruggedized and non-ruggedized DRYSTIK models.
**Humidity level achieved after 300 minutes at 22-28° C with 100% internal pump duty cycle and no desiccant.
DRYSTIK Performance Graphs

The following diagram shows the equipment configuration used to conduct DRYSTIK performance tests. In tests requiring desiccant, a large drying tube containing fresh desiccant was placed between the RAD7 Outlet and the DRYSTIK’s Purge In port. Each test ran for 1200 minutes, with 10 minute cycle intervals. Changes in the reported relative humidity were observed over time and graphed. These test results apply to all DRYSTIK ADS-2, ADS-3 and ADS-3R models, with both standard and brushless pumps.

DURRIDGE DRYSTIK humidity test configuration

DRYSTIK Configurations (Click Test ID number for graph)

Test ID Desiccant Flow Rate Duty Cycle Ambient Temperature Ambient Relative Humidity
01

Yes High Flow 100% 28° C (144″), 24° C (48″), 22° C (12″) 42% (144″), 34% (48″), 31% (12″)
02 Yes High Flow 30% 29° C (144″), 24° C (48″), 23° C (12″) 40% (144″), 34% (48″), 32% (12″)
03 Yes Low Flow 100% 33° C (144″), 24° C (48″), 23° C (12″) 43% (144″), 34% (48″), 31% (12″)
04 Yes Low Flow 30% 29° C (144″), 23° C (48″), 23° C (12″) 41% (144″), 34% (48″), 30% (12″)
05 No High Flow 100% 28° C (144″), 24° C (48″), 23° C (12″) 48% (144″), 34% (48″), 32% (12″)
06 No High Flow 30% 29° C (144″), 23° C (48″), 23° C (12″) 40% (144″), 34% (48″), 30% (12″)
07 No Low Flow 100% 29° C (144″), 24° C (48″), 22° C (12″) 39% (144″), 34% (48″), 27% (12″)
08 No Low Flow 30% 28° C (144″), 24° C (48″), 23° C (12″) 48% (144″), 30% (48″), 32% (12″)

Ruggedized DURRIDGE DRYSTIK ADS-3R (Open)

Ruggedized DURRIDGE DRYSTIK ADS-3R (Open)

Ruggedized DURRIDGE DRYSTIK ADS-3R (Closed)

Ruggedized DURRIDGE DRYSTIK ADS-3R (Closed)

DURRIDGE DRYSTIK ADS-3R Faceplate

DURRIDGE DRYSTIK ADS-3R Faceplate


Documentation

DRYSTIK User’s Manual (PDF)


Media

DRYSTIK Model ADS-3 Standard Configuration Diagram

DRYSTIK Model ADS-3 Standard Configuration Diagram

DRYSTIK Model ADS-3: Alternative Drying Tube Placement Diagram

DRYSTIK Model ADS-3: Alternative Drying Tube Placement Diagram

DRYSTIK ADS-3 Physical and Technical Specifications
Dimensions 11.5″ x 7.75″ x 3.25″ (29 cm x 20 cm x 8 cm)
Weight 4.40 pounds (1.54 kg)
Shipping Dimensions 14″ x 14″ x 14″ (36 cm x 36 cm x 36 cm)
Shipping Weight 12 pounds (5.4 kg)
LCD Display Output 2 line x 16 character alpha-numeric display
Case Material Beige ABS Plastic Enclosure
Power 12V DC in (1.25A)
ADS-3-12-P1 12-inch DRYSTIK

$1,146.00Add to order

ADS-3-48-P1 48-inch DRYSTIK

$1,221.00Add to order

ADS-3-144-P1 144-inch DRYSTIK

$1,495.00Add to order

Optional Brushless Pump for the ADS-3

$112.00Add to order

DURRIDGE DRYSTIK ADS-3

DURRIDGE DRYSTIK ADS-3

DURRIDGE DRYSTIK ADS-3 Faceplate

DURRIDGE DRYSTIK ADS-3 Faceplate

DRYSTIK ADS-3R (Ruggedized) Physical and Technical Specifications
Dimensions 13.75″ x 11.5″ x 5.75″ (35 cm x 29 cm x 15 cm)
Weight 7.20 pounds (3.27 kg)
Shipping Dimensions 14″ x 14″ x 14″ (36 cm x 36 cm x 36 cm)
Shipping Weight 15 pounds (6.8 kg)
LCD Display Output 2 line x 16 character alpha-numeric display
Case Material Rugged Black Pelican Case
Power 12V DC in (1.25A)
ADS-3R-12-P2 12-inch Ruggedized DRYSTIK

$1,612.00Add to order

ADS-3R-48-P2 48-inch Ruggedized DRYSTIK

$1,652.00Add to order

ADS-3R-144-P2 144-inch Ruggedized DRYSTIK

$1,785.00Add to order

Ruggedized DURRIDGE DRYSTIK ADS-3R (Closed)

Ruggedized DURRIDGE DRYSTIK ADS-3R (Closed)

High Quality Pumps and Mounting

In 2013 the DRYSTIK design was updated with a high quality pump, mounted on a shock- and sound-absorbing bridge plate. The new pumps increase the expected life span of newly assembled DRYSTIK devices to 5,000 hours of constant use (or 25,000 hours assuming a typical 20% pump duty cycle). The improved pump is offered in both brushed and brushless varieties. Existing DRYSTIKs may be shipped back to DURRIDGE to be upgraded to the pump of your choice.

Improved Brushed Pump Installation

$270.00Add to order

Improved Brushless Pump Installation

$344.00Add to order

 
Related Products
12-inch Passive DRYSTIK

(not in case, without pump or Duty Cycle Controller)

Passive DRYSTIK wand to detect radon entry points

The 12-Inch Passive DRYSTIK consists of open tubing with a wand-like handle that can be aimed at possible radon sources. The Passive DRYSTIK will preserve a container of desiccant for two months of continuous use, a significant improvement over its standard useful life span of 10 days.

Principle of Operation

The Passive DRYSTIK operates on a principle involving two tubes, one inside the other. The inner tube is made of NAFION, a Teflon based material that permits the movement of water molecules, while blocking air and radon. The air sample flows along the inner tube on its way to a drying unit, while the space around the inner tube is purged with dry air coming from the outlet of the RAD7.

$342.00Add to order

DURRIDGE 12-Inch Passive DRYSTIK

12-inch Passive DRYSTIK

Water Switch

Prevent water from entering the DRYSTIK and other sensitive devices

The DRYSTIK is very effective at removing moisture from the air, but it is not effective if liquid water is allowed to enter the device. The optional Water Switch accessory addresses this. The Water Switch is a reed switch with a magnet embedded in a float around it. The device is packaged in a small, airtight container with hose connections, and is placed upstream of the DRYSTIK Model ADS-3. When the Water Switch fills up, it cuts the power to the DRYSTIK, preventing its pump from sucking in liquid water.

$119.00Add to order

  • DURRIDGE Water Switch Accessory
    Water Switch Accessory
  • DURRIDGE Water Switch configuration diagram
    Water Switch Configuration Diagram
Documentation

Water Switch Manual (PDF)

External Solenoid Valve Accessory

To activate higher airflows triggered by the ADS-3R

The optional External Solenoid Valve Accessory temporarily activates higher airflows which may be triggered by the DRYSTIK ADS-3R at regular intervals. This is useful for pumping short-lived thoron into the RAD7 before it decays. Using CAPTURE software, the DRYSTIK can be configured to enable and disable the Solenoid Valve as needed.

External Solenoid Valve Technical Specifications
Normally closed Coming Soon
Turn On Voltage and Peak Current Coming Soon
Hold On voltage and Current Coming Soon
Dimensions 4.25″ x 2″ x 1.25″ (10.8 cm x 5.1 cm x 3.2 cm)
Weight 4.9 ounces (1.40 g)
Power Socket Coming Soon
Hose Socket Coming Soon
On Air Flow Resistance

Coming Soon

$230.00Add to order