Attachment_7_-_Government_response_to_RFI_Questions_r1.pdf

HSHQDN-17-R-0003

Attachment 7 Questions & Answers

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Question Answer

OR-1 What is the exposure rate in uR/hr at the detector for the Co‐ 57 and Ba‐133 sources in the configuration stated?

Exposure rate is not being specified. DNDO will only specify the detection requirement as a specific radionuclide, shielding condition, and flux from a specified decay photon (energy region of interest). This provides the magnitude and spectral composition of the radiation that must be detected.

OR-1 Does this requirement suggest that the instrument will have a 30 second integration time?

No. Exposure time or dwell time is simply the time the source and detector are in proximity to each other (i.e., exposed), not to be confused with integration time of the device.

OR-1 The use of a pressurized ion chamber to determine the background and control the flux is problematic. PRDs are not sensitive to high energy particles typically associated with cosmic radiation. For example, a reading with a PIC may yield a value of 7.5μR/h that would translate to 2.5μR/h for the PRD, leaving 5μR/h attributed to cosmic radiation (depending on altitude). Since the level of cosmic radiation is directly affected by altitude, it is unknown when using a PIC, whether a high dose rate is due to high NORM or high cosmic background.

Agree. Scaling of the specified flux conditions for evaluation purposes will be done using a device more appropriate than the GE RS High Pressure Ionization Chamber (HPIC). Radiation background measurements corresponding to that originally reported based on the HPIC are:

5.75 μR/h using a 2 x 2 inch NaI scintillator with reported energy range of 25 keV to 3 MeV.

6.25 μR/h using a Victoreen Fluke 451P pressurized ion chamber with a reported energy range of 20 keV to 2 MeV.

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Question Answer

OR-1 The defined background range of 0.34μR/h to 25μR/h is extremely large. The dose rate spans more than 2 orders of magnitude and should be narrowed to better represent the true field conditions. For example, the 0.34μR/h, measured with a PIC, can only be achieved in a deep underground lab. If that is a target lab, the conditions and challenges will be very different than the lab at 25μR/h. We do not feel that scaling the flux in this situation will mitigate all of the differences- ambiguity of the composition of the background (gamma vs cosmic) and huge variation of the signal to noise ratio- even if the flux correction was only performed for the gamma portion of the background.

ANSI 42.32-2006 specifies a normal background condition of 5 - 25 uR/hr. DNDO has reduced the lower limit of potential backgrounds to 0.1uR/hr(See OR-8) to correspond with the lower background seen in the maritime environment. This range of background radiation was added to the clarification to indicate that DNDO may test the detection requirement at any level within that range. The flux to be detected will be appropriately scaled based on the background conditions of the test. It was not intended that the range of background in the clarification be as measured by a PIC, only that the devices will encounter a wide range of background conditions from very low to very high and must function across this range.

FR‐01‐

The requirement states that the device shall alarm immediately upon exposure while the Threshold states the device shall alarm within 2 seconds. Which is it?

As fast as possible, but not more than 2 seconds.

FR‐

01‐01

In the real world a 2 second integration time is unrealistically long, based on the walking speed of most people. Why is this very long time constant being specified as an acceptable performance parameter?

Agree; faster response time is better. Time-to-alarm is specified as no more than 2 seconds per ANSI N42.32- 2006 Section 6.3. This does not imply a specification for a detector’s integration time.

FR‐01‐

What is meant by adjustable, what is meant by configurable, and what is meant by user set?

How are these different?

In the end, the differences are subtle and not informative.

Intent is that the user be able to set and/or change the alarm/notification level. DNDO will update the requirement to avoid confusion.

OR‐2 What is the exposure rate in uR/hr at the closest point of approach for Co‐57 and Ba‐133 in each of the described test configurations?

Exposure rate is not being specified. DNDO will only specify the detection requirement as a specific radionuclide, shielding condition, and flux from a specified decay photon (energy region of interest). This provides the magnitude and spectral composition of the radiation that must be detected.

OR‐2 What is the acceptable false alarm rate for these tests?

See OR-6.

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Question Answer

OR‐2 The clarification states that for the test the instrument must be worn on the belt, presumably of a human test subject. Where on the belt will the instrument be worn? What will be the orientation of the source with respect to the test subject?

Intent is that the face of the device that points outward while being worn on the torso of an operator is the face of the device that will be oriented towards the test source.

OR‐2 Can you please be more specific describing how the flux to be detected will be scaled as the square root of the ratio of the current test site? What does this mean?

The detection parameters of source strength or flux, distance of closest approach and speed are based on a defined radiation background. When conducting a test, if the measured background differs in magnitude from the background the requirement was based on, the flux used in the test must be adjusted to correspond to the measured background. The flux to be detected in test is the flux defined in the requirement multiplied by the square root of the ratio of measured background at the test site to background used to define the requirement.

𝐹𝑙𝑢𝑥𝑡𝑒𝑠𝑡 = 𝐹𝑙𝑢𝑥 𝑟𝑒𝑞𝑢𝑖𝑟𝑒𝑚𝑒𝑛𝑡√ 𝑏𝑎𝑐𝑘𝑔𝑟𝑜𝑢𝑛𝑑𝑡𝑒𝑠𝑡 𝑏𝑎𝑐𝑘𝑔𝑟𝑜𝑢𝑛𝑑𝑟𝑒𝑞𝑢𝑖𝑟𝑒𝑚𝑒𝑛𝑡

OR‐2 Can you please explain the meaning of the sentence in the Clarification: “Background exposure rate to the background exposure rate on which the requirement was based.”

See above. This clarification statement refers to the ratio of backgrounds used to scale the flux to be detected to account for the difference between the background the requirement is based on and the measured background at a test facility.

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Question Answer

OR‐2 Can you please explain what is mean in the Clarification by the following sentence: “Distance and speed both must be scaled with the square root of the ratio of the target activity to the actual activity of the test source used.”

In order for a requirement to be written for a dynamic scan, the scan setup must be quantitatively defined. A dynamic scan setup is not quantitatively defined until values are assigned to each of the following three parameters:

The source strength (or radiation level at a stated reference distance)

The separation distance at the closest point of approach (CPA)

The transit speed.

This minimum set of parameters, which arises directly from the properties of point sources and linear motion, imposes implicit temporal constraints on the detector’s response. A practical problem arises during performance testing when the available test source does not have the same gamma-ray emission rate as specified in the requirement. The key feature of a dynamic scan is the temporal profile of signal as seen at the detector during the scan. By “at the detector” is meant the radiation incident on the detector rather than the radiation as measured by the detector. For two setups to be quantitatively equivalent, they must present the detector with the same temporal profile of incident signal. If one of the three parameters is changed, then the other two must be quantitatively scaled to retain the temporal profile, at the completion of which all three parameters will have been assigned specific new values.

To account for a new point source strength, the square root of the ratio of new/old source strengths is used as a factor by which to multiply the old CPA distance and the old speed.

Alternatively, the factor can be determined by moving the new source to a CPA value that gives the same radiation signal level as did the old point source strength at its CPA distance; the factor is then the ratio of new to old CPA distances, and it is to be multiplied by the old speed to compute the new speed.

If CPA distance (or speed) is changed first, then the ratio of new CPA distance (speed) to old CPA distance (speed) must be multiplied by the old speed (or CPA distance) to obtain the new speed (CPA distance), and the old source strength must be multiplied by the square of that ratio to obtain the new source strength.

OR‐2 What is the difference between the test source and the target?

"Test source" is the source actually available and used in a test. The "target" is the desired/required source to duplicate a specified set of conditions.

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Question Answer

OR‐2 The Clarification states that an HPGe detector will be used to measure and determine the counts in the appropriate region of interest and then determine the flux at the point where the PRDs’ reference points will be placed. If this is referring to the counts the PRD is detecting, how will that value be established based on the data from the HPGe detector? What does region of interest refer to? The physical space the test subject will be moving through? What is meant by the statement that the PRDs reference points will be placed, as a moving test rather than a static one is described? What is the PRD reference point?

Reference point of an instrument: The effective center of the detector (N42.32-2006 Table 1) or the physical mark or marks on the outside of a detector used to position it a point where the conventionally true value of a quantity is to be measured (N42-32-2006, section 3.37).

OR‐2 In the real world normal walking speed is considerably faster than the 0.61 m/s speed stipulated in this requirement. Forcing operators to slow down to this speed would severely constrain their ability to search large areas.

Why is this very low speed being specified as an acceptable performance parameter?

The relative speed between the source and detector for the threshold condition is set at 0.61 meters/second (2 feet/second). This corresponds to approximately half normal walking speed. The objective requirement uses the same flux-levels but increases the desired relative speed to a full walking speed of 1.5 meters/second.

OR-2 The use of a pressurized ion chamber to determine the background and control the flux is problematic. PRDs are not sensitive to high energy particles typically associated with cosmic radiation. For example, a reading with a PIC may yield a value of 7.5μR/h that would translate to 2.5μR/h for the PRD, leaving 5μR/h attributed to cosmic radiation (depending on altitude). Since the level of cosmic radiation is directly affected by altitude, it is unknown when using a PIC, whether a high dose rate is due to high NORM or high cosmic background.

Agree. Scaling of the specified flux conditions for evaluation purposes will be done using a device more appropriate than the GE RS High Pressure Ionization Chamber (HPIC). Radiation background measurements corresponding to that originally reported based on the HPIC are:

5.75 μR/h using a 2 x 2 inch NaI scintillator with reported energy range of 25 keV to 3 MeV.

6.25 μR/h using a Victoreen Fluke 451P pressurized ion chamber with a reported energy range of 20 keV to 2 MeV.

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Question Answer

OR-2 The defined background range of 0.34μR/h to 25μR/h is extremely large. The dose rate spans more than 2 orders of magnitude and should be narrowed to better represent the true field conditions. For example, the 0.34μR/h, measured with a PIC, can only be achieved in a deep underground lab. If that is a target lab, the conditions and challenges will be very different than the lab at 25μR/h. We do not feel that scaling the flux in this situation will mitigate all of the differences- ambiguity of the composition of the background (gamma vs cosmic) and huge variation of the signal to noise ratio- even if the flux correction was only performed for the gamma portion of the background.

ANSI 42.32-2006 specifies a normal background condition of 5 - 25 uR/hr. DNDO has reduced the lower limit of potential backgrounds to 0.1uR/hr(See OR-8) to correspond with the lower background seen in the maritime environment. This range of background radiation was added to the clarification to indicate that DNDO may test the detection requirement at any level within that range. The flux to be detected will be appropriately scaled based on the background conditions of the test. It was not intended that the range of background in the clarification be as measured by a PIC, only that the devices will encounter a wide range of background conditions from very low to very high and must function across this range.

FR‐02‐

This requirement and OR‐9 appear to contradict each other.

There is a difference between changing background (OR-9) and introduction of and slowly approaching a "source" in the environment. They are also very complimentary in that both address maintaining detection sensitivity during changing conditions, while highlighting the difference between naturally occurring background and other introduced sources.

FR-02-

There should be clarification that it is possible to alarm before reaching the target test position.

Concur. When slowly approaching a radiation source, the detector can/should alarm within 2 seconds of the threshold for detection being exceeded. Based on the detection requirements, an alarm should occur well before reaching the ANSI N42.32-2006 specified 50 uR/hr above background.

OR‐3 At what exposure level must the instrument respond to meet this requirement? ANSI N42.32 section 6.4 is not specific, but rather states that the neutron field will be increased to the required level for detection.

ANSI does not specify an exposure rate. It provides an emission rate of Cf-252, a shielding/moderation configuration, and a distance from the source to the reference point of the device, which describes the conditions at which the detector is required to alarm.

OR-3 Please clarify if ANSI N42.32- 2006 is required.

ANSI N42.32-2006 is required. Section 6.4 defines the threshold DNDO requires for neutron detection.

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Question Answer

OR‐4 The requirement describes a user settable limit to exposure rate or dose rate. Over what range of exposure or dose rate will this user settable limit be adjustable? What integration period will it have?

Instrument range is specified in FR-04-02. The settable limit should be adjustable over the range of the instrument. An integration period is not specified.

FR‐04‐

ANSI Standard 42.32‐2006 section 6.6 describes the accuracy requirements for displayed exposure rates when provided. For instruments with unitless displays, the ANSI standard allows a conversion table to convert the display value to an equivalent exposure rate with the same accuracy requirements of units with displayed values. Is this requirement the same as the

ANSI

standard in allowing conversion tables?

Yes. For unitless displays, if a conversion table is provided, it will be used to convert displayed values to an exposure rate for comparison to the conventionally true value.

FR‐04‐

Small radiation detectors have an energy dependent cross section, consequently their sensitivity depends on the energy of the detected gamma rays.

Normalizing their sensitivity requires either desensitizing them at low energies with absorbing materials or gathering spectral information to accomplish this digitally. Both methods have drawbacks that increase cost and degrade instrument sensitivity.

How much degradation in performance is acceptable to achieve this requirement?

Performance as specified in ORs 1, 2, 3, 4, 5, 6, 7 , and

8. Any "degradation" that causes a device to not meet the thresholds is unacceptable.

FR‐04‐

What is meant by “the conventionally true value”?

See ANSI N42.32-2006, section 3.12.

FR‐04‐

The maximum indicated exposure rates for both the Threshold and Objective are beyond the maximum displayed exposure rate of the vast majority of DNDO owned PRDs. What is the reason for the increase in this requirement?

An analysis of operational environment/encounters has mandated setting the required rates.

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Question Answer

FR‐04‐

What level of precision in exposure/dose rate measurement is required?

Per FR-04-01 and ANSI N42.32-2006, section 6.6 accuracy must be within +/- 30% of the conventionally true value.

FR-04-

Over what time period will the displayed measurement be taken?

FR-04-05 and FR-04-06 simply require the device to continuously display the measure exposure rate either in units of exposure rate (FR-04-05) or a numerical;-scalar value (FR-04-06). For accuracy testing per N42.32-2006 section 6.6, exposure time is not specified, but for test purposes will be minimal, enough time to allow device reading/indication to stabilize and that reading to be recorded.

FR-04-

Please provide a chart that displays dose rate range to desired, corresponding numerical value

DNDO will not specify nor has a desired exposure/dose rate range to corresponding numerical value. This is left to the manufacturer, based on the operating range and capabilities/features of their devices. DNDO only requires the correlation between numerical value and exposure/dose rate be provided.

FR-04-

Please provide a chart that displays dose rate range to desired, corresponding numerical value

See FR-04-05.

OR‐5 Radiation measurement is a statistical process. What is meant by the requirement for operator feedback to rising or falling radiation levels in “Real Time”?

The operator must be able to tell that the radiation level as measured by the device is falling or rising. The more rapid the feedback, the easier it is to determine the point of highest radiation readings.

OR-5 What time constant is expected for this feedback?

A time constant is not specified. However, it must be frequent enough to allow an operator to rapidly locate the point of highest radiation.

FR‐05‐

What is the difference between this and requirement OR‐5?

OR-5 is the operational requirement providing that the capability be available. FR-05-01 adds specificity that the device must provide a visual and/or audible indication of changing gamma intensities. FR-05-01 is simply, does the device have a visual or audible feature;

yes or no? Whereas OR-5 is, "can the operator use the feature to localize a source."

OR‐7 Because of the statistics of the inherently low neutron background count rate, this requirement will significantly reduce the threat detection sensitivity of the instrument.

What is the reason for this requirement?

This requirement establishes an operationally acceptable false alarm rate. Users have to respond to alarms and particularly neutron alarms. Users do not want to react to alarms solely from statistical fluctuations in background and be distracted from other duties or delayed in accomplishing a survey. The allowable rate of false alarms is as specified in N42.32-2006 Section 6.2.

OR‐8 What is the exposure rate for Co‐ 57 and Ba‐133 respectively in the configuration called out in OR‐1 &2, and how close is it to the proposed 25 uR/hr background rate?

Exposure rate is not being specified for OR 1 and 2.

Exposure rate accuracy is highly dependent on the device taking the measurement. DNDO will only specify the detection requirement as a specific radionuclide, shielding condition, and flux from a specified decay photon (energy region of interest). This provides the magnitude and spectral composition that must be detected.

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Question Answer

FR‐08‐

Is the intention of this requirement to have the instrument automatically update the alarm threshold itself during operation or only on start‐up?

The requirement specifies updating background only upon start-up. It does not preclude automatic updates during operation.

FR‐08‐

The use of the term background update is confusing in this context. In normal operation the instrument must have a set Alarm Threshold above which higher gamma count rates cause an alarm to occur. This Alarm Threshold can be set by the operator directly, or can be set by the instrument itself by acquiring gamma count rate data for a statistically meaningful period and then computing an alarm threshold for that environment based on an acceptable false alarm rate. What will the operator change manually? The actual Alarm Threshold? The initiation of a new computed Alarm Threshold? The ability to change the false alarm rate of the computed Alarm Threshold?

The requirement is for the device to have a feature allowing an operator to direct the device to measure and use current conditions as the background and then that background be used by the device's algorithm. DNDO is not specifying how the algorithm function or uses background to set thresholds, but will evaluate devices on their ability to operate in and adjust to the background conditions specified in ORs 6, 7, 8 and 9.

FR-08-

If algorithm from FR-08-01 is sufficiently detailed and explained, would that be enough to show why an automatic rolling background design, that works continuously after startup, is sufficient to meet the intent of this requirement?

No. FR-08-01 requires a feature allowing a user to update/set the background. Each capability, automatic and user specified background updates, both provides for minimizing false alarms on background variations, but DNDO specifically wants the option for a user to be able to manually set the background.

FR‐08‐

Is the intention of this requirement to have the instrument automatically update the alarm threshold itself during operation or only on start‐up?

The requirement specifies updating background only upon start-up. It does not preclude automatic updates during operation.

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Question Answer

FR‐08-

The use of the term background update is confusing in this context. In normal operation the instrument must have a set Alarm Threshold above which higher neutron count rates cause an alarm to occur. This Alarm Threshold can be set by the operator directly, or can be set by the instrument itself by acquiring neutron count rate data for a statistically meaningful period and then computing an alarm threshold for that environment based on an acceptable false alarm rate. What will the operator change manually? The actual Alarm Threshold? The initiation of a new computed Alarm Threshold? The ability to change the false alarm rate of the computed Alarm Threshold?

The requirement is for the device to have a feature allowing an operator to direct the device to measure and use current conditions as the background and then that background be used by the device's algorithm. DNDO is not specifying how the algorithm function or use background to set thresholds, but will evaluate devices on the ability to operate in and adjust to the background conditions specified in ORs 6, 7, 8 and 9.

FR‐08-

If algorithm from FR-08-03 is sufficiently detailed and explained, would that be enough to show why an automatic rolling background design, that works continuously after startup, is sufficient to meet the intent of this requirement?

No. As with FR-08-01, FR-08-04 requires a feature allowing a user to update/set the background. This is in addition to FR-08-03. Each capability, automatic and user specified background updates, provides for minimizing false alarms on background variations, but DNDO specifically wants the option for a user to be able to manually set the background.

OR‐9 Is this requirement for automatic update of the Alarm Threshold based on a changing background environment during operation, or only at startup?

OR-9 intentionally does not specify how to accomplish the objective. OR-9 only requires as background changes, the device adjusts to maintain sensitivity (ORs 2 and 3) and false alarm rates (ORs 6 and 7).

OR‐9 If this requirement is intended for adjusting the Alarm Threshold during operation, how will the instrument know that the background environment is not changing when a weak source is detected?

DNDO is not specifying how the device meets these requirements only that the device have desired performance/capability as specified in the requirement.

OR‐9 How will the operator know that Alarm Threshold has been changed automatically?

There is no requirement that the device inform the operator that an update has been made, though depending on how the algorithm uses background to set/adjust the alarm point this should be logged (OR-11).

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Question Answer

OR‐9 How will operators be trained to use an instrument that is changing its Alarm Threshold constantly?

It is transparent to an operator that the device is automatically updating the background (and potentially the alarm point) based on changes in background. They will be trained to respond to the alarms. Training an operator to constantly be aware of background conditions, and when that might affect the sensitivity or false alarm rate of the device and when they should or shouldn't update the background or settings is much more involved.

OR‐10 There is a wide range of Naturally Occurring Radioactive Materials, not the least of which is Uranium. How will the Instrument know to suppress alarms due to naturally occurring Uranium while retaining the ability to alarm on depleted uranium, which could be indicative of the presence of a threat?

DNDO is purposefully not specifying how to accomplish this objective requirement. However, there are notable differences in the energy spectra of NORM vs processed materials.

OR‐11 The instrument is constantly detecting radiation. Is the intent of this requirement to retain information on continuous radiation detection or just alarms?

Requirement is to record "periodic radiation readings during alarm state." It does not preclude recording continuous radiation readings as long as the device can store data from a minimum of 1 week of continuous operations.

OR‐11 If the intent is to retain just alarm information, at what periodic rate during an alarm should additional readings be taken.

Not specified other than periodically during the alarm state.

OR‐11 This requirement makes no mention of an interface beyond a standard user display interface.

Is there an implicit requirement here for an additional interface besides the user interface? If so, what are the characteristic of that interface?

OR-11a, as updated, provides for interface of device with standard IT equipment so data can be downloaded.

OR‐11 No mention is made of the Alarm Threshold in the stored data.

Does the Alarm Threshold also need to be stored? Does the time of the Alarm Threshold change also need to be stored?

Yes. The alarm threshold setting and the time stamp when set and/or changed should be included in the stored data.

FR-11-

Please clarify what is “stored data”. Alarm information, date/time of instrument, instrument settings, etc.

Minimum required data to be stored: date and time, on/off state, alarm state, state of health, operating hours, and periodic radiation readings in system set units during alarm state. Operational/maintenance state data should be logged when the state changes. ANSI N42.32-2006 section 5.16 provides additional detail.

FR-11-

Is there a reason data storage would not be desired?

Some protocols may preclude collection of data.

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Question Answer

OR‐

11a

This requirement specifies the capability to interface with existing DHS and component information systems. Can you provide additional information on what this entails?

Ability to connect with and download stored data to personal computers and laptops using Windows 7 and higher (to include Windows 10) and/or Win Server 2012.

OR‐

11a

What type of interface is being specified?

A specific type interface is not being specified.

OR‐

11a

What are the DHS and component data security requirements?

Systems that transmit data using a wireless connection (i.e., wireless, Bluetooth, IR) to transfer to DHS information systems shall use encryption that is FIPS

197 (AES‐256) compliant and has received FIPS 140‐2 validation.

OR‐

11a

Please provide the DNDO Interoperability requirements standard

The DNDO Interoperability Policy for the Global Nuclear Detection Architecture referenced in the draft set of requirements is not releasable. However, DNDO has updated the interoperability requirements to better specify what is required. This includes: ability to connect with and download stored data to personal computers and laptops using Windows 7 and higher (to include Windows 10) and Win Server 2012; data format must be compliant with ANSI N42.42-2012; and if data is transmitted using a wireless means (i.e., wireless, Bluetooth, IR), the data must be encrypted and FIPS 197

(AES‐256) compliant and received FIPS 140‐2 validation.

FR‐

11a‐01

Internally stored data is not accessible outside of the electronic hardware, and internal encryption requires additional memory, adds complexity, and will increase cost. What operational need requires encrypting the data internal to the instrument?

Only data transmitted from the device to a DHS system using wireless connections (i.e., wireless, Bluetooth, IR) is required to be encrypted while being transmitted.

OR‐12 For systems with rechargeable batteries, is the down‐time required to recharge the batteries included in this specification?

OR-15 and FR-15-04 address rechargeable battery requirements. Operational availability rate will be affected if a device is unavailable (inoperable) due to lack of battery power.

OR‐12 Is there a reliability specification for systems with rechargeable batteries, such as the minimum number of recharge cycles or the minimum rechargeable capacity?

No. However, FR-15-04 provides a requirement for maximum time necessary to recharge the batteries.

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OR‐12 For systems with replaceable batteries, is the down‐time required to change the batteries included in this specification?

OR-15, FR-15-02, FR-15-03, FR-15-05 address replaceable battery issues. Operational availability rate will be affected if a device is unavailable (inoperable) due to lack of battery power. However, the battery status indication (FR-15-03) allows for advanced warning of battery failure, while ability to change batteries without special tools in the field (FR-15-02) makes it possible to change batteries before it becomes an issue and limit downtime.

OR‐12 the time needed to periodically check and clean the instrument included in this specification?

No. It is assumed that during the periodic check and cleaning the instrument is still available, if needed.

OR‐13 Are there any existing radiation detection instruments, or other complex sensor systems, in the DNDO inventory with documented MTBF of 35,040 hours?

DNDO will not specify or provide the capability of any current systems. The requirement is to provide a very reliable system.

FR‐14‐

What is required to be recorded in the maintenance status file?

State of health ( results of the self-checks and diagnostics, diagnosed malfunctions) and operating hours

FR-14-

How is this file to be output from the instrument?

Downloaded to a windows based PC or laptop. See OR 11a, OR-11b, and FR-11b-01 as updated.

FR‐14‐

Is this file required to be encrypted internally in the data storage hardware?

No.

OR‐15 Is the operational time specification the same for replaceable and rechargeable batteries?

Yes. 1 week is the minimum amount of time required for continuous operations regardless of how the system is powered.

OR‐15 With the false alarm rate specified in OR‐6 there will be 877 false alarms in one year of operation. The power consumption to display these false alarms will considerably exceed the power consumption of normal continuous operation without alarms. Has any thought been given to the total power consumption specification of normal operation with false alarms included?

No. DNDO is using section 5.15 of N42.32-2006, as amended, to increase the time required in a non-alarm state to specify power consumption/battery-life requirements.

FR‐15‐

Does this requirement apply to fresh/recharged batteries or to partially discharged batteries after a period of use?

Fresh, fully charged batteries.

FR‐15‐

What constitutes a special tool in the context of this requirement?

ANSI Standard N42.32-2006, Section 5.15. Special tools are tools not readily available or found in a standard tool kit (e.g., of standard tools are pliers, cross point or flathead screw drivers).

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OR‐17 Solid state silicon photodetectors have markedly degraded performance above 35 degrees Celsius. Does this requirement preclude the use of silicon photodetectors in these instruments?

The requirement provides the operational conditions under which the device shall correctly operate. Choice of design necessary to meet these requirements are left to the vendor/manufacturer.

FR-21-

The requirement is unclear. The threshold is very clear and understood. Please provide additional detail especially as it relates to the “Note: Alarm for detection vice personal protection”

FR-21-03 (tactile indication) and FR-21-02 (audible indication) have the same requirement statement. The intent of the requirement is to specify the minimum set of notifications requiring audible and tactile alerts. The requirement will be modified. The device shall have a tactile and audible alert as specified in the threshold statements for radiation alarms caused by exceeding the set threshold for compliance with ORs 1, 2 and 3 (if applicable,), for safety alerts in compliance with OR-4, and for maintenance/battery alerts. The note was to distinguish between the detection alert for ORs 1, 2, and 3 (if applicable) and the separate/ unique indication for radiation exceeding the safety level as required by OR-4.

This note is not necessary and will be deleted.

FR‐22‐

The terms user friendly and easily operable is ambiguous in this context. Can you please specify what these terms mean and include what level of complexity is acceptable?

"User-friendly" interface/controls are self-explanatory/intuitive, clearly marked, and easy to use.

Easy to use interfaces/controls are efficient (minimal number of actions required, minimal number of control features, minimal input to achieve the desired output), minimizes undesired or unnecessary output to a user and ergonomically sized and positioned (e.g., displays oriented so an operator can see them in the as worn and carried positions, buttons/controls operable with a human finger (no tools like a stylus required) and in the case of the DHS PRD while wearing gloves.

FR-22-

Please define the method of test for this requirement.

DNDO will conduct an operational assessment during which DHS end users will use the device and then provide feedback on the device via survey. ANSI 42.32- 2006, Appendix C provides an example user interface evaluation survey.

FR‐22‐

What level of protection will be required? Switch guards? Double action (push a button and actuate a switch, etc.)?

The requirement does not specify how to meet the requirement or design the device, only that the device pass the test specified in N42.32-2006 section 5.1.

FR‐22‐

Busy displays are confusing to operators in heavy workload environments. Is the intent of this requirement to display all of these parameters at the same time?

Intent is to have the required data available to the operator, but not necessarily all of the data at the same time. Scrolling through numerous displays is also confusing in heavy workload environments.

FR‐22‐

The light emanating from most LCD displays is linearly polarized. Does this requirement preclude the use of LCD displays in the instrument?

No.

Refer-ence

Question Answer

OR‐23 How will this be tested? By a vote of the operators?

An Operational Assessment will be conducted.

Knowledgeable operators will be trained on the devices and use them in operationally relevant scenarios.

Operators using a Likert scale will be asked to rate how easy it was to use the device.

OR‐23 How does the manufacturer design an instrument to this specification?

Manufacturers are expected to apply applicable human factors engineering.

OR‐23 Will there be additional design guidance on what is acceptable and what is not?

No. In acquiring Commercial Off The Shelf systems, it is assumed that devices have already been designed, and there is no opportunity nor desire for a vendor to reengineer the systems. The program will survey users after operating the devices and record their opinions.

OR‐24 The manufacturer typically does not train the users, except by providing a User’s Manual. Does this mean that the User’s Manual must be able to be read in 60 minutes? How does this translate into pages of text?

The requirement is that a user, after a maximum of 60 minutes (threshold)/ 30 minutes (objective) of training, be able to place the system in operation, set user adjustable features, monitor system status, recognize and understand notifications, localize a source of radiation, turn system off, and conduct basic maintenance. DNDO will establish a contract item for vendors to provide training materials and support. This includes training materials, Train-the-Trainer, and Technician-level training, and may also include operator basic training support. Training materials should consist of, at a minimum, handbooks or downloads, reference guides, user manuals, and quick start guides. If available, Web-based training may be provided.