API Bull E2:2006 pdf download

API Bull E2:2006 pdf download.Bulletin on Management of Naturally Occurring Radioactive Materials (NORM) in Oil and Gas Production.
The State organizations or the Occupational Safety and Health Administration (OSI IA) establish limits for exposure of personnel. The annual occupational limit listed in 29CFR1910.1096(b)(l) is 5 rem (0.05 Sv). L)unng any calendar quarter. the dose to the whole body shall not exceed 3 rem (0.03 Sv) as listed in 29 CFR 19l0.l096(bM2Xi); however, monitoring is done at some fraction of the limit value, generally 10 to 25% of the allowable limit. Work area radiation levels in the general industry segment are typically far below this regulatory level. Therefore. routine personnel radiation exposure surveys are not frequently done.
3.1.6 Personnel Internal Radiation Dose Assessment
Ambient airborne NORM concentrations are normally evaluated by tiltenng a high-volume air sample and having the tilter analyzed by a radiometnc laboratory. NORM deposits in equipment and piping do not present any airborne exposure concerns during normal operations. During maintenance or dismantling activities, airborne NORM exposure concerns are minimized by the application of typical industrial hygiene practices such as keeping NORM deposits wet and using respiratory protective equipment. On the other hand, during grinding, cutting, chipping and sanding, and during removal of NORM scale, airborne activity may occur. Under such conditions, it is advisable to evaluate employee exposure to ambient airborne concentrations of NORM.
Personnel exposures are evaluated by the same sampling and laboratory methodology except that personnel wear lapel air samplers that operate at 2 to 5 liters per minute versus the higher flow rate ambient air pumps. In both techniques. it is essential to know the volume of air sampled along with the radiometric results in order to calculate the airborne NORM concentrations.
3.2 INTEGRATION OF SURVEY TECHNIQUES
Numerous radiological measurement techniques have been discussed above. It is important that the individual performing the survey clearly understand and be trained in the procedures being used. The operator should identify the purpose of the survey and the values to which the results will be compared. The appropriate measurement technique will be selected based on this information. For example. if the objective of the survey were to determine the need for workers who need to be monitored for occupational exposure to radiation and radioactive materials, the survey would include detennination of exposure rate and an evaluation of estimated internal doses. Survey measurements might include exposure rates and airborne concentrations of radioactive material. In contrast, if a property is being released from regulatory licensing, survey techniques would likely include gamma surface scans, exposure rate measurements, and determination of concentrations of NORM in soil. The selection of sursey techniques is based on the objective of the survey and the guidelines to which the results of the survey will be compared.
3.3 INSTRUMENT CARE, MAINTENANCE, AND CALIBRATION
Portable survey meters typically used tO conduct NORM surveys are generally quite rugged; however, the associated detectors and probes must be handled with care. As a mailer of good practice. connecting cables should not be sharply bent because frequent sharp bending of the connecting cables will break the internal cable wire. Ilattery contacts need to be kept clean and free of corrosion residue. In humid environments, or if instruments are used infrequently, batteries should be removed from survey meters when the instruments are not being used. Survey instruments should be kept clean, and detectors (probes) need to be kept free of NORM residue.
NORM survey instruments should he returned to the manufacturers (or other qualified instrument calibration agents) at least annually (semi-annually in some jurisdictions) for general maintenance and calibration, Individual meters, detectors, and connecting cables should be calibrated as discrete instruments (units). Switching components between units voids the calibration(s). It is particularly important to ensure that instruments that are used to measure exposure rate are calibrated and respond appropriately to the radiation field present
Instrument operational checks should be conducted before each use of an instrument (or after the detector has been dropped or banged against a solid object, etc.) to ensure that the instrument is functioning properly and pmviding representative readings. Operational checks include:
Battery check. Switch the meter dial to the “Battery” position and observe that the meter indicator moves into and remains in the accepted range. or depress the “Battery” button on the meter and observe the dial.