The U.S. Navy, its M.O.P.P Procedures, Detection Equipment and Decontamination (Radiation)

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posted on Mar, 16 2011 @ 12:02 PM
The U.S. Navy, its M.O.P.P Procedures, Detection Equipment and Decontamination as relatated to Radiation

With all the rumors going around about this ship doing this and this sailor doing that, I’d like to get some information out to the community regarding the Surface Navy and how they deal with Nuclear Warfare.

** For all you TL;DR types: The Navy’s ships and personnel while at sea are well protected and prepared for any radiation type issues. And below is how they do business.

Warning: Learning Zone Ahead

My Source? This was my job for 7 years on two ships while I was stationed in Japan from 01-07. Anyway, you can look it up too if you want. Start with this link (a PDF) if you must.


First, what is a M.O.P.P level? Mission Orientated Protective Posture. These differ slightly from Sea commands to Shore commands, and here we will be talking about the sea commands.

Note the word “attack” is used throughout. The protective postures are also used in the event a ship passes through a chemical cloud or is exposed to fallout etc…

All operations are conducted under the MOPP system, even when there is no threat. There are four levels of MOPP—from Level-1, the least protection, to Level-4, the most protection.


All ships are at this at all times. General Condition of Readiness.

MOPP Level-1
1. Individual protective equipment and medical supply items are issued to shipboard personnel and maintained at respective battle stations. Protective masks are fitted for immediate use.
2. Inventory stowed chemical/biological defense equipment and supplies.
3. Set readiness Condition III and material condition YOKE, if not already set.


Intelligence suggest an attack using Chemical, Biological or Radiological weapons is possible.

MOPP Level-2
1. For both chemical and biological threats, protective mask is in a carrier and worn on the person.
2. Preposition decontamination supplies in decon stations and at repair lockers. Preposition stowed detection and monitoring equipment, supplies, and empty canteens as specified in the ship’s CBR Defense Bill.
3. Set material condition ZEBRA (modified).


Intelligence suggest an attack using Chemical, Biological or Radiological weapons is probable.

MOPP Level-3
1. Install new filter canisters on protective masks, maintain in a carrier and on the person. Provide wet-weather gear for donning over other protective clothing and equipment for weather deck activities. Don over garment trousers and coat with hood down. Don chemical-protective over boots. Stow personnel decontamination kit in mask carrier. Stow chemical-protective glove set and medical supply items in pocket on over garment coat. Initiate pyridostigmine pretreatment regimen.
2. Go to general quarters (GQ) (readiness Condition I may be relaxed and readiness Condition II set at CO’s discretion); set material condition ZEBRA.
3. Fill prepositioned canteens with potable water.
4. Activate decontamination stations and contamination control areas (CCAs) and assure operability. Post detection and monitoring teams.
5. Post and monitor detection equipment and materials as designated by the ship’s CBR Defense Bill.
6. Activate countermeasures washdown system intermittently.


MOPP 4: Intelligence suggest an attack using Chemical, Biological or Radiological weapons is imminent.

MOPP Level-4
1. Don protective mask and secure hood over head and around mask. Don chemical-protective glove set.
2. Direct ship to GQ (if not previously in effect).
3. Initiate continuous monitoring and operation of detection equipment.
5. Activate countermeasures washdown system to operate continuously. The setting of MOPP levels may be different at various locations around the ship. This depends on the mission, work rate, and heat buildup in these battle station areas (engine rooms, combat information center, flight deck, and so on).

Shipboard Detection Equipment

The AN/PDR-27

A portable, watertight, battery-powered, low-range survey radiac. Two Geiger-Mueller (GM)
tubes are mounted in an extendable probe. A spare GM tube set is included in the carrying case. The probe is fitted with a beta shield. Six alkaline D-cell batteries
(BA-3030/u) power the unit. If the alkaline batteries are unavailable, you may use carbon-zinc, D-cell batteries (BA-30). The AN/PDR-27 provides both visual and audible indications of gamma and beta radiation levels.

The AN/PDR-43

A battery-powered, high-range, beta-gamma RADIAC set used for low- and high-level surveys and, in some cases, personnel monitoring. It uses a GMdetector and has a built-in Krypton-85 source to check for proper operation on all three operating ranges: 0-5 R/hr (gamma), 0-50 R/hr (gamma), and 0-500 R/hr (gamma). GM detectors, such as the AN/PDR-43 adjust quickly to changes in the level of radiation intensity. Even when shifting to a different range scale, only 1 second is required for meter adjustment. At intensities above 500 R/hr, the meter pegs but does not become saturated.

The AN/PDR-65

(This is what detected the radiation in Yokosuka after the reactor explosions)

Designed to detect and measure gamma radiation. The set consists of two primary elements as follows:

1. The DETECTOR UNIT. The detector unit must be located at or near a masthead. The field of view for the detector of an enveloping base surge cloud and resultant fallout must be relatively unobscured. As a result, if suitable scaling factors are available, gamma dose rates at any location inside the ship can be estimated from the masthead radiation intensity data.

2. The RADIAC METER. The radiac meter is installed on the bridge. One or more auxiliary readouts are located in DCC and other prime locations. The radiac meter has two types of displays—one is for dose rate and the other is for accumulated dose. The primary
meter displays the dose rate. The small counter registers the accumulated dose in rads by counting the rad pulses from the detector. Each time a dose of 1 rad is accumulated, the radiac meter sounds a loud beep. The range of the small counter is 0 to 9,999 rad. Gamma
intensity is indicated on one of the following four ranges: 0 to 10 rad/hr, 0 to 100 rad/hr, 0 to 1,000 rad/hr, and 0 to 10,000 rad/hr.

The DT-60/PD

A gamma radiation dosimeter with a usable range of 10 to 600 R.The DT-60/PD is a solid-state package in the form of a locket designed to be worn on a chain around the neck. Inside the black plastic casing of the DT-60/PD is a phosphate glass. When the phosphate glass is exposed to ultraviolet light, it emits an orange light. The intensity of the orange light is proportional to the amount of radiation the glass has received. The DT-60/PD stores the dose information indefinitely and is a permanent record of the amount of exposure to radiation.

The readings from a DT-60 are measured by using a CP-95...It's like a computer. You insert the DT-60, pull a lever and there you, got your reading.


All ships have personnel decontamination stations strategically placed throughout. Usually laid out like this:

All personnel exposed to the weather while a ship is receiving fallout from a nuclear detonation shall reenter through a decontamination station or a contamination control area (CCA). Those who must perform duties topside after the deposition of fallout has ceased are considered to be potentially contaminated. They may be required to reenter through a decontamination station or CCA, depending on the intensity of the radiation from the fallout remaining and its location on the ship. The basic procedures in the decontamination process are the same for all ships.

Variations from ship to ship are due to differences in the design and location of decontamination stations.

Countermeasure Washdown System

Also, all ships are equipped with a Counter Measure Washdown (CMWD) system (mentioned in MOPP 3 & 4) (we have a quarterly op test on this. Lots of fun!)

Hope you learned something, those who read it. Anyway, bottom line. As incompetent as our government can be at times, I can assure that the Navy is well prepared and organized when it come to issues pertaining to radiation.

edit on 3/16/2011 by Juston because: (no reason given)
edit on 3/16/2011 by Juston because: (no reason given)
edit on 3/16/2011 by Juston because: (no reason given)
edit on 3/16/2011 by Juston because: (no reason given)

posted on Mar, 16 2011 @ 12:20 PM
Excellent info for those wondering! Thanks for the post op. I always hated those dang airlock door to go outside the , where you had to latch the first hatch first then wait a second then do the other door...

posted on Mar, 16 2011 @ 12:28 PM
reply to post by Juston

Good thread Juston!
When I was a MT on the USS G.W. Carver (SSBN-656)(Gold) we didn't have the water wash-down systems, it was always OW. Had to keep the screen doors closed at all times!! LOL. "Green Board" and all that. We did wear tritium detectors though because of the warheads not the reactor.
Although the last part of the '70's I was an IC on the USS San Diego (AFS-6) we did have the WWDS and quarterly drills, etc.
Good thread, maybe ole monkey wrench will use this as another dimension of his thread...his cousin went through the decon station but was still bleeding out his ears and vomiting but did not get any blood on the keyboard while sending his emails to "uncle bob" LOLOLOL

F&S, sir!
edit on 16-3-2011 by tomdham because: (no reason given)

posted on Mar, 16 2011 @ 01:34 PM
reply to post by JJRichey

Yeah, as annoying as the CPS doors are (especially the maintenance and HEPA filters) I'm glad we had them in case TSHTF

posted on Mar, 16 2011 @ 01:40 PM
half of all mopp suits have been shown to be flawed in some way and don't offer the stated protection for some reason. internal docs i read in the uscg back in 2000.

on another note, our military should give them to japan, who would reimburse us and we could buy newer better suits. win/win

1. they get our suits which ae better than nothing.
2. we help them out
3. they gratefully pay us for them
4. we get new better suits. and super good brownie points. what do you think about this idea?

posted on Mar, 16 2011 @ 02:25 PM
reply to post by rebeldog

That is correct. In fact in, I believe 2002-2003, the Navy contracted out to get new suits, called ACPG's.

(I remember this vivdly, as we had to do a complete inventory of the old suits, by size, lot number and date of manufacture etc... Those were some long nights!)

posted on Mar, 16 2011 @ 03:46 PM
Wow, this brings back some memories! This was my MOS 54B L5 in the Army. I trained on all that equipment.

And spot on with the Training. During every FTX we usually spent part of a day in MOPP4 and did a decon wash site. The military took this stuff pretty serious.

posted on Mar, 16 2011 @ 09:02 PM
reply to post by tomdham

I was hoping the same, but alas, his thread was closed pending staff review. Oh well. I just hope some people (other than prior military
) found the information useful.

posted on Mar, 16 2011 @ 09:13 PM
I think a better way to put it would be like this:

The US Navy has many plans and ideas in place, and a lot of equipment built by the lowest bidder. Much of it is maintained and operated by 19 year old kids. In the event of an actual emergency, there would be some degree of reduction in casualties. How much reduction? Only time can tell. These systems are untested.

posted on Mar, 16 2011 @ 09:17 PM
reply to post by Juston

The Airforce has the Jlist suit. It fits better then the old suits except for the G string that keeps your top secured. It's a real pain in the rear. Only time I had to wear my chem gear during a real world contingency was during Operation desert fox. Exercises don't count though.

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