RDS Frequently Asked Questions (FAQ)

The Radiological Detection System is a suite of equipment that is used for detection, classification, and quantification of gamma (photon), beta, alpha, x-ray, and neutron radiation. The equipment utilizes Geiger-Mueller (GM) tube, scintillation, photomultiplier tube (PMT), and solid-state semiconductor-based technology to detect the various forms of radiation. Detection capabilities are found in the Base Unit and in six different probes, each suited to different missions or purposes.

Top row left to right:

• Alpha-Beta Probe (DT-727/PD PROBE RADIAC)

• Beta Photon Probe (DT-728/PD PROBE RADIAC)

• Field Instrument for Detection of Low Energy Radiation (FIDLER) Probe (DT-724/PD PROBE RADIAC)

• Neutron Probe (DT-725/PD PROBE RADIAC)

• Sensitive Gamma Probe (DT-726/PD PROBE RADIAC)

• Small Area Gamma Probe (DT-729/PD PROBE RADIAC)

Bottom row:

• Base Unit (IM-281/PD RADIACMETER)

The initial systems fielded to U.S. Army came with compact disc (CD) containing two draft manuals, TM 3-6665-381-13&P Operator and Field Maintenance manual Including Repair Parts and Special Tools List for Base Unit Radiological Detection System , NSN 6665-01-671-4539 and TM 3-6665-382-13&P Operator and Field Maintenance manual Including Repair Parts and Special Tools List for Probes, Radiological Detection System.

The final manual, to be published late 2024 or early 2025 will be Army TM 3-6665-383-14&P; Air Force TO 11H4-2-22-1; Marine Corps TM 00385A-13 Technical Manual Operator, Field and Sustainment Maintenance Manual Including Repair Parts and Special Tools List for Base Unit Radiological Detection System (RDS) AN/PDR-83.  This manual will include the Base Unit and all Probes as well as ancillary equipment that is a part of the RDS System.

For US manuals, log in to the Joint Acquisition CBRN Knowledge System (JACKS) at https://jacks.jpeocbrnd.army.mil/ to find the draft manuals. Once published, please access them through https://armypubs.army.mil/.

The US Navy is producing a separate technical manual, refer to the organization in your Service that fielded the RDS to you for receipt of the proper technical manual.

Canada military units shall receive both an English and Canadian French version of Operator Manual for Canadian Radiological Detection System (CRDS) Base Unit and Probes. English CRDS Operator Manual is manufacturer part number V062904, Canadian French CRDS Operator manual is manufacturer part number V072065.

For Canada manuals, please submit a request to your First Line Maintenance provider.

The Base Unit and probes do not contain internal radioactive sources.  The configuration issued may contain individual check sources, a button check source of less than 1 microCurie (µCi) of cesium (Cs)-137 and some sets may contain a check source of less than 30 nanoCurie (nCi) of thorium (Th)-232. Please refer to the following Warning statements when using a check source:

WARNING: Avoid prolonged use of Check Sources, return them to case or other protective location promptly after each use to minimize exposure. Do not ingest source. Do not attempt to open or crush source housing. Do not handle damaged sources. The cesium (Cs-137) check source contains less than 1 microCurie (μCi) of Cs-137.

Coordinate disposal with unit Radiation Safety Officer (RSO). Failure to follow precautions may result in injury or death.

WARNING: Avoid prolonged use of Check Sources, return them to case or other protective location promptly after each use to minimize exposure. Do not ingest source. Do not attempt to open or crush source housing. Do not handle damaged sources. The thorium (Th-232) check source contains less than 30 nanoCurie (nCi) of Th-232. Coordinate disposal with unit Radiation Safety Officer (RSO). Failure to follow precautions may result in injury or death.

The only hazardous materials, other than the check sources, used in operation of the RDS are batteries. These are standard commercial batteries.  Internally and not handled by the operator is one button cell BR2032 battery that maintains the clock in the Base Unit. Changing of the internal clock battery is done by qualified maintainers only. Operators will be required to change the batteries that power the system while operating the RDS.  It requires four (4) AA batteries.  Although Nickel Metal Hydride (NiMH) are recommended for longer operating time, and they are rechargeable, alkaline AA batteries may be used as well. Do not mix battery types. Please refer to the following WARNING statement for handling of batteries:

WARNING: Batteries, under normal conditions of use, are hermetically sealed. Potential for exposure should not exist unless the battery leaks, is exposed to high temperature, is accidentally swallowed or is mechanically, physically, or electrically abused. Batteries should not be opened or burned. Exposure to the ingredients contained within or their combustion products could be harmful causing respiratory irritation, skin irritation, eye irritation and chemical burns. Do not handle leaking or damaged batteries without neoprene or rubber gloves. Do not puncture, mutilate, or attempt to disassemble batteries. Do not heat them above 212°F (100°C). Failure to follow precautions may result in injury or death.

Maintainers may encounter additional hazardous chemicals such as solvents, adhesives, and lubricants while conducting maintenance, please ensure to follow all WARNING and CAUTION statements found in the technical manual.

The Radiological Detection System is a versatile suite of equipment and not all operators may need the capability of every probe or piece of ancillary equipment. The US Military Services and Canada Department of Defense have analyzed the needs based on the unit’s mission and operating parameters and created different configurations based on their needs.

For USMC and USA, configurations are laid out in the Introduction to Repair Parts and Special Tools List (RPSTL), Chapter 12. Both Services have National Stock Numbers (NSN) assigned and type designators for their configurations.

For USAF and USN, multiple configuration types have been defined.  Please refer to the organization in your Service that fielded the RDS to you for additional details on those configurations.

For Canada, the CRDS Operator’s Manual, Chapter 1 provides a picture and table of all items found in each of the types of kits that are fielded. 

Please note for all Services, there are some configurations that contain multiple transit cases, your FIDLER Probe, Neutron Probe and for Canada Sensitive Gamma Probe may be in a separate transit case from the rest of your configuration. Transit cases and their labeling also vary for each of the US Services and Canada.

The procurement of additional RDS equipment must go through your Military Service following the proper channels for your requests based on the Service you are a part of. If you are unsure of who to contact, try the following:

• For US – Place an inquiry at Joint Acquisition CBRN Knowledge System (JACKS) at https://jacks.jpeocbrnd.army.mil/ through the CBRN-Information Resource Center. All military personnel may sign in to the CBRN-IRC using their Common Access Card (CAC).

• For Canada please contact your First Line Maintenance provider.

All RDS operational and maintenance items are assigned a National (or NATO) Stock Number (NSN) and are available through military supply channels. NSNs can be found in TM-3-6665-383-14&P, Chapter 12 and 13 or CRDS Operator’s Manual, Chapter 1.

Follow all proper channels for your Military Service.  Each Service has their own maintenance concept, please ensure you follow the guidance in your technical manual, technical bulletin, or operator’s manual.

Some ancillary equipment and consumables such as the mylar window for the Alpha-Beta Probe may be ordered at the operational unit level. Please refer to the source, maintenance, and recoverability (SMR) codes in TM-3-6665-383-14&P, Chapter 12 for US Army, US Air Force, and US Marine Corp to determine if the item is orderable at the operational unit level and work with your supply and maintenance personnel assigned or supporting your unit.

There are two parts to ensuring your Base Unit or Probe is working correctly. 

1. Performing a quick exterior inspection can rule out damage that might prevent the item from working properly, following the Before Preventive Maintenance Checks and Services (PMCS) will walk you through the inspection process ensuring you check all important items on the exterior.

2. The last step in the Before PMCS will take you to the right Work Package/Section for preparation for use of the item. This will include applying power (batteries or AC/DC Power Adapter), turning it on, attaching a probe to the Base Unit, checking units and thresholds to ensure they are set correctly, and finally a functional check of the detectors in the system. Follow the procedure as written in the technical manual/operator’s manual using the proper check source to see the readings per the given range and performance of the RAD test. Follow the proper troubleshooting steps should the item not meet the requirements given in your technical manual/operator’s manual and seek the next level of maintenance as necessary should it be indicated.

For TM-3-6665-383-14&P, Operator PMCS can be found in Chapter 4.

For CRDS Operator’s Manual, Chapter 10, Section 1 contains the Operator PMCS.