Naturally occurring radioactive material

Naturally occurring radioactive material (NORM) is material found in the environment that contains radioactive elements of natural origin. NORM primarily contains uranium and thorium (elements that also release radium and radon gas once they begin to decay) and potassium. These elements are naturally decaying and are considered a primary contributor to an individual's yearly background radiation dose.

Pipeline contaminated with NORM

Where can NORM be found?

NORM is often found in its natural state in rocks or sand. It can also be associated with oil and gas production residue (such as mineral scale in pipes, sludge and contaminated equipment), coal ash (produced from burning coal for energy production) and on filter media (such as the used filters from municipal drinking water treatment equipment). NORM can also be present in consumer products, including common building products (like brick and cement blocks), granite counter tops, glazed tiles, phosphate fertilizers and tobacco products.

Some industries may regularly come into contact with NORM – for instance, those engaged in the production of oil and gas, phosphate fertilizers, forest products and thermal electricity; mineral extraction and processing; tunneling and underground workings; metal recycling; waste management; and water treatment.

Did you know?

• NORM is material naturally found in the environment that contains radioactive elements.

• The handling and disposal of NORM within Canada is regulated by the provincial and territorial governments.

• The transport, import and export of NORM must follow Canadian Nuclear Safety Commission (CNSC) regulations.

• NORM-contaminated equipment and waste should only be handled by a person with appropriate radiation training.

How is NORM regulated?

In Canada, NORM is regulated by the provincial and territorial governments, each having its own specific regulations on the handling and disposal of the material. The Canadian Guidelines for the Management of Naturally Occurring Radioactive Materials have been developed by the Federal Provincial Territorial Radiation Protection Committee (FPtrPC) to harmonize standards throughout the country and ensure appropriate control over NORM; however, provincial regulations should also be consulted.

NORM is exempt from the application of the Nuclear Safety and Control Act and its regulations except under the following circumstances:

• when NORM is associated with the development, production or use of nuclear energy as set out in the General Nuclear Safety and Control Regulations

• when NORM is imported into Canada or exported from Canada as set out in the Nuclear Non-proliferation Import and Export Control Regulations

• the transport of NORM when the specific activity is greater than 70 kBq/kg or has an activity concentration exceeding 10 times the activity concentration limit for exempt material values set out in the International Atomic Energy Agency’s (IAEA) Regulations for the Safe Transport of Radioactive Material, as set out in the Packaging and Transport of Nuclear Substance Regulations, 2015. As with all other dangerous goods, NORM must also be transported in accordance with Transport Canada’s Transportation of Dangerous Goods Regulations as applicable. Contact the CNSC if you require information on the transport of NORM above the limit specified

How is NORM detected?

Survey meter detecting NORM in the sludge of a contaminated vac truck

Natural background radiation comes from the ground, building materials, air, food and cosmic rays. Depending on where you live, levels of this type of radiation can vary. Radiation readings above typical background radiation levels may indicate the presence of NORM. Determining the type of material present is essential to assess what, if any, precautions need to be taken with the material. This process is called characterization. Radiation surveys used for characterization should be conducted by personnel trained in radiation safety or by external consultants to determine if the suspect material is NORM or man-made radioactive material.

How should NORM be handled?

Although concentrations of NORM are usually quite low and the risk is minimal, safe handling of the material is important since higher concentrations of NORM can result when the material is processed. This is often referred to as technologically enhanced NORM, or TENORM.

Because specific safety measures may be required to protect workers who handle NORM-contaminated equipment or NORM waste, NORM should only be handled by a person with appropriate radiation safety training and training in the precautions for hazardous industrial substances.

Best practices for individuals and facilities encountering NORM include:

• providing training and procedures to staff where there is the possibility of encountering NORM

• not eating, drinking or smoking in areas where the presence of NORM is a possibility

• storing NORM and any contaminated materials (including clothing) and waste in a designated area with access limited to authorized personnel

• minimizing operations that may generate dust containing NORM (e.g., cutting, grinding or polishing)

• minimizing the time spent in NORM-contaminated work areas and storage areas

• maximizing the distance from the source when handling or storing NORM

• using appropriate shielding to minimize dose rates from the material if warranted

• disposing of NORM-contaminated materials efficiently, to avoid stockpiling the material

Other (or more involved) measures should only be considered under the direction of personnel trained in radiation safety, specialized in the handling and disposal of NORM. Precautions can include:

Pipeline cleaning

• decontaminating equipment that has been exposed to NORM prior to disposal

• using personal protective equipment, including non-porous coveralls, boots and gloves, and protective eyewear and respirators, depending on the situation

• ensuring that pipes are sealed and ground covers are used, to prevent environmental contamination

• preventing dust inhalation, by keeping NORM materials damp with water

• ensuring that all workers are checked for any contamination with NORM before leaving the work area

• evaluating and decontaminating areas of potential NORM contamination by using high pressure washing or high-efficiency particulate air (HEPA) filter vacuuming