DP-12

[marconmeteo]

DP-12 Radiometer

69fieldgear_DP12main.jpg

DP-12 Technical Data:
Russian Designation: дегазационный прибор, дп- 12 (Decontaminating Device, DP-12)
Manufacturer: State Factories
Year Adopted: Uncertain at Present
Operational Status (1996): Russia – In active service. Other Users – Various Eastern European nations and former Soviet Republics.
Radiation Types Detected: Beta and Gamma
Detection Range: 0.05 - 200 Rads (0.5 - 2000 cGy)
Operation Principle: Geiger-Muller Tube
Power Source: 1x Type 3336 battery (4.5 volt)
Dimensions (as carried w/o transit case)

Length: 24 cm 9.45 inches
Height: 13 cm 5.12 inches
Width: 20.4 cm 8.03 inches
Cable Length: 158 cm 62.2 inches


Brief Operational History

The DP-12 radiation meter is designed monitor radioactive contamination of vehicles, personnel, and equipment. It can also be used on board aircraft for rapid area surveys of contaminated areas. The Chinese M-78 is very similar to the DP-12 in outward appearance.

The operational history of the DP-12 Radiometer is very difficult to reconstruct largely due to two factors: the tendency for Russian sources to omit its date of introduction, and the general lack of specificity regarding it in Western sources. What we have been able to reconstruct is that the device entered service at least as early as 1961. The device has also been observed in several Soviet photographs in our possession dating from the 1960's or 1970's. The American Army field manual FM-100-2-3 also lists the device as being in the Soviet inventory in 1984. It was also noted in three editions of Jane's NBC Protection Equipment, the latest being 2002-2003. Given the sweeping changes that the Russian army underwent in the mid-2000's it would not be surprising to find that the device has either been replaced or moved to reserve status.

Method of Operation

The DP-12 operates by using a Geiger-Muller tube mounted inside a hand-held probe. The probe is connected by a flexible cable to the control box which provides the actual measurement. It is sensitive to both Gamma and Beta radiation. It is fitted with a metal collar over the probe with openings of different sizes. This collar can be rotated around the probe to shield out Beta 1, Beta 2, or all Beta radiation depending on the readings required. The probe can also be attached to a retractable shaft which enables it to be placed close to difficult to reach objects - such as the underside of contaminated vehicles. The unit is powered by a single rectangular 4.5 volt cell known as a Type 3336 battery. The battery measures approximately 67mm long, 62mm wide, and 22mm thick. They are most commonly found in Europe and the former Soviet Union.

Another feature of the control box is a six setting analog display panel, which can be illuminated by flipping a switch. A spare light bulb is included for this purpose. A headset can also be used with the unit to allow the operator to hear when the device detects radiation.

When in use the DP-12 survey meter is worn on the operator’s chest by means of a plastic carry strap. The unit must then be calibrated. Full operating and calibration instructions are listed on the inside cover of the control device.

They require the user to set the main switch to ‘series’ and then power up the device. He must then move the metal needle over the measuring scale to the indicated position. Then he must reset the device. The operator does this for each of the 5 measuring scales (the first setting is not used).

The Scale Settings

The DP-12 is highly sensitive and can measure both Beta particles and Gamma radiation. The device has six settings that allow it to measure a range between 0.05 and 200 Rads. These scales are each color coded and can be seen on this table.

Setting Color Monitoring Range Radiation Type
1 White Device Off None
2 Black 0 - 5 Beta 2
3 Red 0 - 500 Beta 2
4 Blue 0 - 125 Beta 1 / Gamma
5 Green 0 - 25 Beta 1 / Gamma
6 White 0 - 5 Beta 1 / Gamma


Once calibrated the user then moves to the area of suspected contamination and holds the probe unit is held about one inch (25mm) away from the surface to be measured. The operator then checks the reading on the control device. The probe also has the ability to monitor the contamination of fluids since the metal probe unit is waterproof.