Frequently Asked Questions

American Portable Nuclear Gauge Association

The APNGA FAQ section is comprised of questions that are frequently asked on the “Ask A Question” section as well as emphasis items found to be lacking during regulatory inspections.

What is radiation?

Radiation is energy given off by matter in the form of rays or high-speed particles. All matter is composed of atoms. Atoms are made up of various parts; the nucleus contains minute particles called protons and neutrons, and the atom’s outer shell contains other particles called electrons. The nucleus carries a positive electrical charge, while the electrons carry a negative electrical charge. These forces within the atom work toward a strong, stable balance by getting rid of excess atomic energy (radioactivity). In that process, unstable nuclei may emit a quantity of energy, and this spontaneous emission is what we call radiation.

There are many familiar forms of radiation. For example, we use light, heat, and microwaves every day. Doctors use x-rays to see inside our bodies. Radio and television waves bring us our favorite shows. All of these are forms of radiation. Radiation is also naturally present in our environment, as it has been since before the birth of this planet. The sun and stars send a constant stream of cosmic radiation to Earth, much like a steady drizzle of rain. Also, the Earth itself is a source of terrestrial radiation. Radioactive materials (including uranium, thorium, and radium) exist naturally in soil and rock. Essentially all air contains radon, water contains small amounts of dissolved uranium and thorium, and all organic matter (both plant and animal) contains radioactive carbon and potassium. In addition, all people have internal radiation, mainly from radioactive potassium-40 and carbon-14 inside their bodies from birth and, therefore, are sources of exposure to others.

Where does radiation come from?

Radiation is naturally present in our environment, as it has been since before the birth of this planet. In addition, radiation can be produced artificially, as in medical x-rays and microwaves for cooking. Nonetheless, most people are not aware of all the natural and man-made sources of radiation in our environment.

How far does radiation travel?

Travel distance depends on the type of radiation, as does the ability to penetrate other materials. Alpha and beta particles do not travel far at all, and they are easily blocked. By contrast, gamma rays, x-rays, and neutrons travel a significant distance and are much more difficult to block (particularly for large radioactive sources).

How are radioactive materials used?

In medicine, radioactive materials are used for diagnostic and therapeutic purposes. Similarly, in biological and biomedical research, they are used to test new drugs and to study cellular functions and bone formation in mammals. In addition, radioactive materials are used in various industrial applications to protect food and blood supplies, increase the safety of roads and buildings, locate new energy sources, light emergency exits, warn of fires, and more. All users must be licensed by the NRC or by “Agreement States” authorized by the NRC.

What do radioactive sources look like?

Radioactive sources used in moisture density gauges are typically “sealed” and encased in two laser fused metal canisters. They are very small; the final double encapsulated metal container is typically about the size of a pencil eraser.

How can I tell if something is radioactive?

You can’t, without the help of a radiation detector. In addition, it is important to know what type of detector you have and the type of radiation — alpha, beta, gamma, x-ray, and/or neutron — that it can detect. Scanning an object with a typical gamma/x-ray radiation detector will not detect alpha particles, for example.

Why do you need to be careful around radiation?

For the same reason we need to be careful around open flame, toxic chemicals, or knives. Used and stored properly, for example, a knife can help us prepare and eat food; misused, it can cause injury and possibly death. Similarly, when handled correctly, radioactive materials have many beneficial uses; misused, however, it can pose a significant danger. Ionization can cause damage within a cell, which could eventually lead to cancer, a mutation in genetic material, or more immediate types of physical harm to humans.

Why shouldn’t you pick up a radioactive source and put it in your pocket?

It really depends on the source. Depending on their size and activity, many sources contain enough energy to cause significant damage to human skin and tissue.

What is the worst radiation can do to you? How can this be prevented from this happening?

Radiation can kill you (if you are exposed to enough of it) by doing so much damage to your bodily systems that your body can no longer function. The regulatory system for radioactive materials is designed to prevent the possibility that anyone could receive an exposure even close to the levels that might inflict short-term damage.

The simplest preventions against harmful radiation exposure are time, distance and shielding. Limit the time you are exposed to the radioactive source; increase the distance between you and the source; and shield yourself by placing objects between you and the source. These concepts form the basis of nuclear regulation so that we may enjoy the beneficial uses of radioactive materials while minimizing the risk to public health and the environment.

If radiation is dangerous, why do we use radioactive material?

One could think of radioactive materials as a knife. Used and stored properly, a knife can help us prepare and eat food; misused, it can cause injury and possibly death. Similarly, when handled correctly, radioactive materials have many beneficial medical, industrial, and academic uses.

Who regulates radioactive materials and radiation exposure?

The U.S. Nuclear Regulatory Commission (NRC) is the Federal agency responsible protecting the health and safety of the public and the environment by licensing and regulating civilian uses of the following radioactive materials in medical, academic, research, and industrial applications (including the generation of nuclear power).

Of more than 20,000 active source, byproduct, and special nuclear materials licenses in place in the United States, about ¼ are administered by the NRC, while the rest are administered by 35 Agreement States.

Why doesn’t the NRC regulate the radiation in my microwave oven?

There are a number of reasons, stemming primarily from our governing legislation (particularly the Atomic Energy Act of 1954, as amended). Microwave radiation is non-ionizing radiation. It causes electrons to vibrate, thereby generating heat, but it does not have sufficient energy to cause physical harm by removing electrons from atoms. The type of radiation that actually has sufficient energy to remove electrons from atoms is called ionizing radiation. The NRC regulates man-made, and some specific types of naturally occurring ionizing radiation.

How can exposure to radiation be minimized?

Time, distance, and shielding measures minimize your exposure to radiation in much the same way as they would to protect you against overexposure to the sun (as illustrated in the following figure).

Are there pills to take to protect someone from radiation?

Potassium iodide (KI) protects people from thyroid cancer caused by radioactive iodine, a type of radioactive material that can be released in nuclear explosions. KI should only be taken in a radiation emergency that involves the release of radioactive iodine. Since the use or release of radioactive iodine from a “dirty bomb” is highly unlikely, KI pills would not be useful.

How is someone decontaminated if they get radioactive material on them such as from a dirty bomb?

A “dirty bomb” is one type of “radiological dispersal device” that combines a conventional explosive (such as dynamite) with radioactive material. Most dirty bombs would not release enough radiation to kill people or cause severe illness. However, these steps can be taken to reduce the risk of contamination:

  • Remove contaminated clothes as soon as possible, and place them in a sealed plastic bag. The clothing could be used later to estimate a person’s exposure.
  • Gently wash skin to remove any possible contamination, making sure that no radioactive material enters the mouth or is transferred to areas of the face where it could easily be moved to the mouth and swallowed.

 Is radiation exposure from a nuclear power plant always fatal?

No, routine emissions during normal operation of a nuclear power plant are never lethal. Even in the very unlikely event of a nuclear power plant accident, it would be extremely unlikely that someone would be in an area for a sufficient period of time to receive a radiation dose that would be considered lethal.

Experience has shown that, during normal operations, nuclear power plants typically release only a small fraction of the radiation allowed by the NRC’s established limits. In fact, a person who spends a full year at the boundary of a nuclear power plant site would receive an additional radiation exposure of less than 1 percent of the radiation that everyone receives from natural background sources. This additional exposure (about 360 millirems — a unit used in measuring radiation absorption and its effects) has not been shown to cause any harm to human beings.

Why can’t a nuclear gauge explode like a bomb?

A gauge does not have enough radioactive material — or the right kind of material — to cause an explosion. It does not have the capability to produce a burst of energy that one would associate with a bomb.

Even a nuclear reactor does not explode.  The material in a reactor is distributed in such a way that it does not release energy instantaneously; rather, it is a controlled reaction that sustains energy production for beneficial purposes.

What types of training are offered on the APNGA website?

a.  Gauge Safety Certification Training
b.  U.S. D.O.T. Hazardous Materials (HAZMAT) Training (includes IATA)
c.   Radiation Safety Officer (RSO) Training
d.   Annual Refresher Training
e.  “Do It Yourself” Annual Audit

The following self-help tutorials are also offered to aid the gauge user in understanding the materials and their role in handling and operating a gauge:

a.   “Step-by-Step” Guide for the gauge user
b.   “How To” Guide for preparing a Radiation Safety Program
c.    “Gauge Operations Photo Tutorial”

Each course will issue a certificate with the completion of the class. The Gauge Safety Certification Class includes a test that must be completed with at least a 70% passing grade. The course can be repeated if the first attempt is not successfully completed.

Classes are accepted in all 50 states. Go to “View My State ” for more details.

The USDOT HAZMAT Refresher Course is based on the 49 CFR 172 Subpart H training requirements (includes IATA requirements) and is eligible for use in all states. The RSO and Annual Refresher classes as well as the “Do It Yourself” Annual Audit are designed to meet license requirements and can be used in all states. Check with your state and your license conditions for any unique requirements.

Who must be trained?

Any person handling or using a gauge must receive nuclear gauge safety certification training. The initial nuclear gauge certification training must include HAZMAT training.

Is HAZMAT training required?

Yes. Acknowledgement of HAZMAT training will be stated on the Gauge Safety Certificate. Subsequent completion of HAZMAT Refresher classes will print a separate certificate.

Who is considered to be a HAZMAT employee?

HAZMAT employees are defined as any individual that directly affects HAZMAT transportation or safety including a person that:

a.  Prepares HAZMAT for transportation including documentation, labeling and marking. This includes clerical workers that type the bills of lading or other transport documents.
b.  Loads or unloads the gauge
c.  Services, tests, modifies, repairs or qualifies the gauge as HAZMAT-ready
d.  Is responsible for the safety and security of the gauge
e.  Operates a vehicle used to transport the gauge

What HAZMAT topics must be covered?

HAZMAT training must include the following topics:

a.  General awareness/familiarization
b.  Function-specific safety
c.  Driver safety and security training

Is RSO training mandatory?

RSO’s must take the same initial Gauge Safety Certification Class as the basic gauge user. But the RSO Course continues beyond the initial class, delving into the more in-depth responsibilities of the RSO position that all RSO’s must be familiar.

What about Annual Refresher Training?

The Annual Refresher Class is offered to help meet the requirements of your Radiation Safety Program/Annual Audit. The Annual Audit requires the RSO to annually review operating and safety procedures, including HAZMAT requirements, with every employee.  The Annual Refresher Class covers the basics of these requirements. The RSO should likewise review the basics with each employee, including a tour of the storage area, transport safety and security procedures, operating procedures, and emergency procedures.

The Annual Refresher Class will cover the basics of this requirement and will issue a certificate that serves as the required documentation of this requirement.

Can you work with a gauge before you receive training?

No, you must complete training before handling or operating a gauge.

Can I perform HAZMAT functions before I am trained?

You can perform certain functions, such as preparing paperwork, for an initial 90 days, but only under the direct supervision of a trained individual. After that you must complete HAZMAT training.

What if I received HAZMAT training from another company?

As long as it is still valid and you have a copy of the training certificate you are qualified to perform HAZMAT functions.

Does the APNGA HAZMAT training class meet the requirements of HAZMAT training and testing?

Yes, but the RSO must oversee the test and sign the certificate.

Does the company have to maintain HAZMAT training records?

Yes. Keep records for every trained HAZMAT worker on file including their name, HAZMAT training date, training materials, name of HAZMAT trainer (APNGA), and the certificate stating that the employee has been trained and tested.

When I finish the on-line APNGA Gauge Safety Certification Training Courses can I immediately operate or transport a gauge?

The RSO determines and authorizes an individual to use a gauge.

At the same time you are reading the APNGA materials and tutorial materials you should also be receiving Radiation Safety Program familiarization from the RSO. While a training course can cover the basics of gauge safety, security, transport, gauge operation and license compliance the RSO must cover the unique features of the office, storage area, gauge brand and model, and the specific applications followed by the company. These features include:

a.  A tour of the company’s facility including the gauge storage area. The employee should be shown how the gauges are secured and restricted from unauthorized individuals. The employee should be shown the location of posters and forms.
b.  The employee should be given a copy and explanation of operating and emergency procedures.
c.  The employee should be shown how a gauge is secured and transported in a vehicle.
d.  The employee should be shown a gauge in use at the worksite.
e.  The employee should be shown the website of the regulatory agency.
f.   The employee should be shown the website of the gauge manufacturer.
g.  The employee should receive hands-on training with the gauge in use by the company, including unique safety features of that gauge and methodologies in use by the company. The APNGA course materials will cover the mechanical safety basics of handling and operating a gauge, but because there are 20+ different gauges on the market, the RSO needs to show the employee the specifics of the gauge in use by the company.

A combination of the training offered on the APNGA and the guidance by the RSO will qualify the employee to operate and transport a gauge.

The training certificate will have a statement that includes the above line items that must be signed by the RSO. The RSO will also sign a statement that the employee completed the closed book test under the direct monitoring of the RSO.

If all of these requirements have been met at the completion of the test the Gauge Safety Certification will be considered valid.

How much time do I have to complete the training classes?

As long as you need, at-your-own-pace within the six month enrollment period. Classes are good for six (6) months from the date of enrollment.

Your understanding of the materials is vital to properly controlling radioactive materials and protecting the public and yourself. There is too much material, including rules, regulations, procedures, forms, and emergency responses, to learn and absorb in one sitting.

Regulatory inspections have shown that over 80% of licensees have violations. The NRC has released a statement that the current level of gauge thefts and gauge damage is unacceptable. APNGA classes offer the viewer the ability to spend as much time as necessary to study and understand the materials. Likewise, the materials are always available for “after the fact” review and reference.

Internet training, partnered with the company RSO, allows for a more in-depth and comprehensive coverage of the material. Consider that the setting where the employee will be studying the material is the exact setting that they will be conducting gauge operations on a day-to-day basis. The whole training process “comes alive”. Everything you are learning can be attributed to the area that surrounds you. You can’t do that in your typical “live”, away from the office, setting.

Traditionally, employees had to wait weeks for a live training class to be available. And then they had to take off work and travel to the class. This can be very expensive, especially if the journey requires overnight accommodations, meals, gas or flight and car rental costs, not to mention the lost work days.

But APNGA classes are available on any internet connected computer. If needed, employees can study the materials at home during the evening or on weekends.

The APNGA materials, “Ask A Question”section, FAQ’s, tutorials, and access to the RSO, will allow the employee the time and interaction to better understand the materials. When the employee feels they are ready the APNGA training module and test will confirm whether the employee is prepared to carry out their role in safely handling a gauge. If the employee does not pass in the first attempt, the program allows them to revisit the materials and take a second test.

For new arrivals to our country the APNGA website material can be viewed in multiple languages. It’s as easy as a click of the mouse.

APNGA classes are also designed to get the RSO more involved in the training and everyday oversight of gauge operations.

I’m in an Agreement State and want to use my gauge on a military base. Do I need reciprocity?

Yes. The NRC maintains regulatory jurisdiction over military and some other federal government installations. Contact the regional NRC office that oversees the state you are located in.

I will be traveling to another state to use my gauge but will be passing through a third state to get there. Which states do I need reciprocity?

Only in the state where you will actually be doing the work. Do not remove your gauge or stay overnight in the third state.

How do I know if I’m in an Agreement State or a NRC State?

There are currently 35 Agreement States and 15 NRC (non-Agreement) States. Current NRC states Virginia and New Jersey are due to become Agreement Sates in 2009. Washington, D.C. and U.S. Territories are regulated by the NRC. Many federal government installations, including most military bases, are under the jurisdiction of the NRC.

Click on the “View My State ” section and select your state to see if you are in an Agreement State or NRC State.

How does an Agreement State differ from a NRC State?

The Atomic Energy Act of 1954 gave the Atomic Energy Commission, now known as the Nuclear Regulatory Commission, the sole responsibility to regulate the civilian uses of nuclear materials. Section 274 of the Act allows the NRC to enter into an agreement with a State for discontinuance of the NRC’s regulatory authority over some materials licensees within the State. The State must show that its regulatory program is compatible with the NRC’s and adequate to protect public health and safety.

35 states have set up their own state agency to regulate gauge licensees. In a sense, your license is an agreement with the state to regulate the use of gauges within your company.

Do I need a special driver’s license to transport gauges?

No. Radioactive Yellow II level gauges do not require a special driver’s license.

Do I need special liability or auto insurance if I own a gauge?

Generally speaking, no. But if you inquire about it with an insurance company I’m sure they will be happy to present you with a policy.

What is meant by Type “A” Package?

Type “A” Package refers to the case the gauge is housed in. This U.S. D.O.T. approved case must be used to transport the gauge.

What is the difference between an IAEA Certificate of Competent Authority and a Special Form Certificate and where can I get them?

There is no difference. “Special form” refers to the double encapsulation shielding that encases and seals the radioactive pellets. The IAEA Certificate of Competent Authority relates to the quality control testing that ensures the double encapsulation can hold up under extreme conditions, including heat, bending and impact. An IAEA approved third party testing company must conduct these tests and approve the manufacture of the special form sealed source.

The special form sealed sources are purchased by gauge manufacturers and placed in the gauge.

IAEA stands for International Atomic Energy Agency.

The IAEA Certificate of Competent Authority/Special Form Certificate can be obtained from the gauge manufacturer. See their website or contact them. Note that the certificate has an expiration date. Updated certificates can be downloaded from the gauge manufacturer’s website.

What is a SSD (Sealed Source and Device) sheet and where can I obtain one?

A SSD sheet is an approval certificate issued for the design and manufacture of a portable nuclear gauge. Gauge manufacturers must submit documentation to their state’s regulatory agency to gain approval for a new design of gauge before it can be manufactured and sold.

The SSD sheet details the design of the gauge and states the purposes for which the gauge will be used. Each gauge is assigned a SSD number. The SSD information is entered into a reference database that all regulatory agencies can access.

When applying for a portable nuclear gauge license you must obtain the SSD number and information from the gauge manufacturer and submit that information on the application. This lets the regulatory agency know which device to reference in their information database.

What is the difference between a MSDS (Material Safety Data Sheet) and an emergency response sheet?

For portable nuclear gauges, an emergency response sheet takes the place of a MSDS sheet. Like a MSDS sheet, the emergency response sheet contains information about the precautions one should take with hazardous materials and what emergency actions one would take in the event of damage or fire to the gauge.

The emergency response sheet, along with a shipping bill of lading, must be readily available to the driver whenever the gauge is transported.

Can I sell my gauge to another party?

Yes, provided they have a license that allows them to possess that exact brand and model of gauge. Obtain a copy of their license and make sure that the gauge you sell them does not exceed the quantity of gauges they are licensed for. Call their regulatory agency if you have any questions.

Make sure to get a dated bill of sale that details the transfer of the gauge including gauge and source serial numbers. Check with the regulatory agency to see if there is a formal document required. Make sure the gauge you are selling has a current leak test.

Upon transfer of the gauge make sure you adjust your inventory sheet.

Should I put radioactive signs on the outside of my vehicle whenever I transport a gauge?

No. You never want to “placard” your vehicle when transporting a Yellow Radioactive II level portable nuclear gauge. Placards are only required for higher quantity Yellow Radioactive III devices.

Do I have to detour or pull over for inspection when I see a sign that tells me that hazardous materials, including Radioactive 7, are restricted in a tunnel, on a bridge or in a city.

Generally, no. These signs are for placarded vehicles that transport higher levels of radioactive materials. If in doubt, follow the directions.

What is a standard block and standard count?

A standard block is used to give a quick check of the gauge’s ability to measure density and moisture. While in the standard mode the gauge will test the number of density and moisture counts received by the detector tubes. The number of counts are compared to previous standard counts. If the current count is acceptably close to previous counts it will pass. If the count is outside an acceptable range it will fail.

There could be several reasons why a standard count would fail. One could be the amount of time that has elapsed since the last standard count. Remember that the radioactive material in your gauge is always decaying. The amount of decay since the last test might be sufficient enough that your current counts are outside the acceptable range for a passing comparison. If you are concerned that the time interval could be the problem you can re-check the gauge by performing four new and separate counts. This will wipe out the old tests stored in the gauge or the tests that were manually recorded. Average the new counts, take a new standard count and compare it to the average of the new counts. You should find that the new test is now within a acceptable range of 1% density and 2% moisture. Check the gauge manual for proper standard count procedures.

If the counts are still not acceptable contact the manufacturer or your service provider for instructions.

Standard counts are also used to adjust for the decay that has occurred to the radioactive sources. Standard counts are very important and should be taken and recorded every day the gauge is used.

The gauge seems to be working fine but the test results don’t seem to match. What are some quick checks I can make on the gauge?

First off, check for any offsets that may still be entered in the gauge.

Make sure you took a standard count and it passed.

If working on soils you may have a situation where the gauge is viewing natural hydrogen as moisture. Soil with high amounts of mica is an example.

Working on frozen materials can fail due to the expansion of moisture. This will lead to higher moisture content and lower density readings.

Asphalt mats with significant surface voids can also be a problem. Use sand or fines to fill in these voids and dampen the effects of the voids.

Make sure the source rod is well seated in the appropriate depth rod notch.

What is a target value?

A target value is entered into the gauge software and used to determine a percentage number indicating the compaction achieved by rolling the material. Each pass of the roller should result in a higher density. The gauge is used to measure and confirm roller actions. A reduction of compaction can occur if the material is over-compacted, which results in a break-down of the material.

The gauge will continue to give independent density and moisture readings.

What is the difference between direct transmission and backscatter methods?

The direct transmission method is generally only used while measuring soils. It requires the operator to hammer an access hole with the drill rod. The gauge is placed on the surface with the source rod opening situated over the drilled hole. The operator depresses the trigger mechanism on the gauge handle and extends the source rod down into ground to the desired depth.

Because destructive testing, such as the drilled hole used with direct transmission, is not acceptable on an asphalt mat, the backscatter method is typically used on asphalt measurements. The operator depresses the trigger mechanism on the gauge handle to release the source rod but only lowers it to the first depth setting. This places the bottom of the source rod at the surface of the asphalt mat. The radiation can measure density to a depth of 3-4 inches.

When working on soils should I use direct or backscatter measurements?

Although soil measurements are usually made using the direct transmission method, the backscatter method can be used for lifts of 3-4 inches. Backscatter is not effective below 3-4 inches below the surface. Soil backscatter is best used when the direct method is affecting the larger aggregate, and therefore the density, of the material.

What are the ASTM and AASHTO standards for the gauge?

ASTM D6938 and AASHTO T310 – In Place Density and Moisture Content of Soil and Soil-Aggregate by Nuclear Methods

ASTM D2950 – Density of Bituminous Concrete in Place by Nuclear Methods