367 11 Radiation Protection Programs R. J. Emery and M. A. Charlton CONTENTS 11.1 Introduction 367 11.2 Anticipation 368 11.3 Recognition 371 11.4 Evaluation 372 11.5 Control 372 11.5.1 Preexposure Controls 372 11.5.2 Laboratory Exposure Controls 373 11.6 Conclusion 374 11.7 Supplemental Reading 376 11.1 INTRODUCTION Radiation protection programs strive to prevent or minimize the harmful effects of radiation sources for those individuals in laboratories involved with the analysis of radioactivity in food and the environment. Sources of radiation inherent to these analytical processes and procedures include ionizing waveforms, particulate radiation, and frequently nonionizing radiation. Sources of ionizing radiation may be used as encapsulated standards for the calibration of counting equipment or in dispersible forms for radiolabeling or internal standardization procedures. Ionizing radiation may also be encountered in the form of radiation producing devices, such as analytical x-ray machines, electron microscopes, or x-ray dif- fraction devices. Sources of nonionizing radiation, in particular high-energy lasers, are also increasingly being used in analytical devices. The unknown analytical sample in the lab may also contain radioactivity. Samples of food and environmental media contain myriad radionuclides in variable concentrations stemming from natural sources or from environmental releases. With all of these different types of sources that might be present in any analytical lab, and the various pathways for potential exposure, the development of a vigilant radiation protection program to protect the health of the individuals associated with the lab activities is considered to be a necessity. DK594X_book.fm Page 367 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC 368 Radionuclide Concentrations in Food and the Environment Laboratory safety programs may be considered integral to an overall philos- ophy of quality control and improvement. A robust safety program prevents contamination, promotes laboratory hygiene, and espouses the “do no harm” philosophy. The enhanced quality embedded within these elements prevents lab- oratory injuries, improves sample analysis, and reduces laboratory overhead costs. Therefore laboratories engaged in quality management programs often dedicate resources to safety enhancements. A radiation protection program is, in effect, a management system that affords an organization the ability to anticipate, recognize, evaluate, and control sources of radiation that might be present in the workplace. Radiation protection programs represent more than just monitoring for the radiation levels present. Robust radiation protection programs include considerations for facility design and engineering controls, personal protective equipment, administrative controls, records review, professional development, and emergency preparedness. Such comprehensive approaches to safety programs have been recognized as standard industry practice, and are considered so important that they are required by some regulatory agen- cies. Although variability exists among various regulatory entities, a finite set of recognized prudent radiation protection program elements are identifiable. This chapter discusses these common elements and provides examples of the measures that can be employed to create a successful program that protects the health and safety of individuals in the analytical laboratory work setting. Other hazards within the analytical laboratory may require similar management systems. Many laboratories possess biological agents, chemicals, and physical agents in addition to the radiological sources outlined in this chapter. These hazards should warrant additional management systems beyond the scope of this chapter. Figure 11.1 outlines a pragmatic schema for describing the overarching prin- ciples of anticipation, recognition, evaluation, and control of radiation sources in the laboratory. Within each principle are subprocedures or considerations which the laboratory should consider to complement their radiation protection program. 11.2 ANTICIPATION The first phase in the development of a comprehensive radiation protection program is anticipating the radiation sources to be encountered. In an effort to anticipate potential workplace hazards, safety must be included in the overall laboratory mission. This tangible management support is critical for new or developing radiation safety programs. Strong executive support transfers into prompt anticipation and remediation of occupational hazards. The anticipation phase typically consists of a review of the overall mission of the laboratory and then the creation of a simple process flowchart that tracks the radiation sources as they pass through the organization. Figure 11.1 contains a conceptual schema to assist in the development of a laboratory process flow- chart. It is important to include in this process diagram both the sources inherent DK594X_book.fm Page 368 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC Radiation Protection Programs 369 in the samples to be analyzed and any sources inherent in the analytical tools and procedures as well. A typical process flow diagram begins with the delivery and receipt of the radiation source. Laboratories should be designed so that sources are received in a controlled area that is away from normal operations. Keeping the source receipt area away from normal operations prevents the possibility of facility contamination FIGURE 11.1 Generic process considerations for the delivery, receipt, preparation, use, and release of radiation sources. ________________________________________________________________________ Process phase Considerations ________________________________________________________________________ Delivery Notification for deliveries Receipt Radionuclide expected Physical form Amount Frequency of receipt Methods for receipt monitoring Addition to inventory Interim storage Security of facility during receipt and interim storage Preparation and use Transport to worksite User training Protective equipment Engineering controls Manipulations Chemical reactions Mechanical manipulations Worksite safety surveys Monitoring Emergencies Quality Assurance / Quality Control Consideration of pathways for releases Postings, access controls Data analyses and interpretation Disposition How will waste or unused sources accumulation occur? Options for return to supplier? Means for assay for verification of content Storage means Processing Disposal recycling Security Removal from inventory Releases in other forms Waste Water Air ________________________________________________________________________ DK594X_book.fm Page 369 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC 370 Radionuclide Concentrations in Food and the Environment if a package is found to be leaking and minimizes the impact of background radiation levels that can adversely impact sensitive radioanalytical procedures. Since some sources may arrive in heavy shipping containers, or may be in various forms of environmental media, consideration must be given to material handling aspects, such as the use of carts or lifts. Upon receipt, the radiation source must be characterized and inventoried so that a complete accounting of the radiation sources present at any time can be maintained. During the receipt phase, consid- eration must be given to the radiological monitoring of the transport package to verify integrity. Provisions for interim storage of any source must be made so that the source is properly secured and maintained in appropriate environmental conditions. For example, some samples may need to be maintained in a frozen state, whereas others may need to be maintained at room temperature conditions at all times. Other samples may hold the possibility of offgassing either potentially hazardous gases or nuisance odors, which may warrant the need for storage with local exhaust ventilation. All of these types of requirements should be anticipated prior to the initiation of activities. After the source receipt phase, the typical process flow leads to the preparation of the source for use or analysis. In this phase, needs for source handling, contamination control, shielding, and local exhaust ventilation should be antici- pated. Accommodations should also be made for upset conditions. For example, if a sample leaks, the pathways for fluid flow should be anticipated. Similarly, if the potential for gases or vapors may be present, the fate of these should be considered as well. Since it is not uncommon for laboratory analyses to subject samples to elevated temperatures, pressures, or chemical reactions in order to extract or isolate targeted components of interest, such processes should also be anticipated, as they can result in releases and possible exposures. The last stage of the process analysis considers the release, discharge, or disposal of the source. By anticipating the need for space and equipment to address the accumulation and subsequent disposal of waste materials, the radia- tion protection program will be developed in a manner that addresses the entire scope of operations. Once a general process flow has been diagrammed, then certain operating parameters can be circumscribed. Estimates describing the number of sources or samples to be received and the average daily and weekly volumes help establish operating bounds for the organization. Such operating parameters are necessarily limited by aspects such as organizational staffing and facility space. Within these operating bounds, accommodations should be made for possible emergency sit- uations, such as when a massive number of samples might be received due to an unusual event, along with envisioned general increases in volume due to organi- zational growth. These operating boundaries can then serve to drive facility design or modification needs and will aid in the facility permitting process as well. Armed with the information gained from the anticipation phase of radiation protection program development, the focus can now be directed toward the recognition phase of the process. DK594X_book.fm Page 370 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC Radiation Protection Programs 371 11.3 RECOGNITION Since humans cannot detect the presence of radiation with any of our sensory pathways, we must rely on other means to recognize its presence. Thus, recog- nition of possible radiological hazards is typically accomplished through a com- bination of worker education and administrative access controls and postings. Worker education should be considered a cornerstone for any radiation pro- tection program. An educated workforce can lead to the installation of a safety culture wherein safety becomes an unquestionable part of every aspect of work. When this type of environment is installed, all of the other programmatic issues fall neatly into place. Although specific regulatory requirements regarding radi- ation safety training vary (Table 11.1 shows the training elements for radiation workers in Texas), all should enable workers to answer the basic following questions: • What are the risks inherent to my job, and where are they? • What steps do I take to perform my job in a safe manner? • Where can I obtain additional information or assistance? • What do I do in case of an emergency? Equally important to providing this basic information, educational programs should also serve as a platform for conveying an organizational commitment to safety and genuine concern for its workers. All too often, excellent educational content is provided via a format that does not effectively convey this message. For example, when a new employee is provided basic radiation safety training via videotape or computer terminal, an unintended message could be that the organization is not truly dedicated to this aspect of operations and is more interested in fulfilling some regulatory requirement. Radiation protection pro- grams should make a concerted effort to avoid this unintended outcome. TABLE 11.1 Radiation Protection Topics Required by Regulatory Authorities in Texas (25 TAC 289.203(c)) Topic Regulatory Reference Storage, transfer, use of workplace radiation sources 289.203(c)(1)(A) Health protection problems associated with radiation 289.203(c)(1)(B) Precautions and procedures needed to minimize exposure 289.203(c)(1)(B) Instructed in applicable radiation protection regulations 289.203(c)(1)(C) Instructed to report any incident or violation 289.203(c)(1)(D) Emergency response procedures and warning 289.203(c)(1)(E) Radiation exposure reports involving the employee 289.203(c)(1)(F) DK594X_book.fm Page 371 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC 372 Radionuclide Concentrations in Food and the Environment To verify that the necessary educational content has been understood by workers, some type of educational assessment tool is needed. This may be in the form of a test or a series of signed acknowledgements, but regardless of the format, it is important to ensure in documented form that the student left the training session with the knowledge to perform work safely, and where to turn if questions arise. An essential part of any radiation safety educational effort includes informa- tion on how to recognize where radiation might be present. Workers should be educated about the various warning signs and barriers that may be placed around areas where radiation sources are used. Descriptions of actual source containers are also useful. 11.4 EVALUATION Once the source term for the work area has been established and the specific locations of use established, then evaluation of the radiation protection program can begin. Typical program evaluations consist of routine surveys to ensure that radiation levels are being maintained as low as reasonably achievable (ALARA) and that contamination is controlled within workspaces and at acceptable levels. Routine surveys should not be limited merely to the detection of radiation, and should include an assessment of programmatic aspects such as the presence of postings, documented worker training, and a review of regular work practices. 11.5 CONTROL Radiation protection programs focus control efforts in three primary phases: prior to the use of radiation sources, during the use of radiation sources, and at the time of ultimate disposition of the source. Each phase of radiation exposure control employs distinct management techniques. The most effective radiation protection program requires a team-based approach with support from executive management, regulatory authorities, facility planners, radiation safety personnel, the laboratory director, and laboratory staff. 11.5.1 P REEXPOSURE C ONTROLS A guiding principle of radiation protection practice involves minimizing or pre- venting radiation exposure before laboratory work begins. This could include consideration of the types of research protocols envisioned, facility construction, engineering control in the form of directional airflow, or security controls in the form of locks and identification card readers. In the laboratory setting, two of the most common administrative controls are peer review safety committees and consideration of radiation source substitution. Many regulatory authorities promulgate standards that mandate health care and research settings convene a properly constituted “Radiation Safety Commit- tee.” In general, a facility Radiation Safety Committee possesses the ability to DK594X_book.fm Page 372 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC Radiation Protection Programs 373 approve new uses of radioactive material, new radionuclides, or even new radio- active material laboratories. The goal of the peer Radiation Safety Committee is to evaluate the hazards of radiation exposure and recommend control measures to the investigator. This peer review methodology for hazard assessment and control has a solid foundation in the laboratory due to the common presence of other institutional review committees (e.g., Institutional Review Board). Radiation source substitution focuses on the availability of alternative research techniques to minimize or prevent exposure to radioactive materials. For example, if the laboratory requests the use of 32 P ( E max = 1.7 MeV B – ), source substitution philosophy dictates the consideration of 33 P ( E max = 0.25 MeV B – ). In this example, a 32 P laboratory nucleotide may be easily substituted with 33 P to accomplish the same scientific goals with a lower energy product. The most effective source substitution occurs prior to exposure and before the laboratory generates data. Therefore formally incorporating these goals into the Radiation Safety Committee’s charter and operations may be helpful. 11.5.2 L ABORATORY E XPOSURE C ONTROLS Radiation safety programs employ a tiered approach to managing radiation expo- sures during routine laboratory operations. This multifaceted approach includes aggressive employee safety training, “dry run” walk-throughs, laboratory director feedback, workplace surveillance, exposure monitoring, and pragmatic radiation protection program review. When taken together as a systematic approach, this exposure minimization plan is circular, with the continual goal of reducing lab- oratory radiation exposures. The dynamic nature of the laboratory work setting dictates an aggressive worker safety training program. Most regulatory authorities will prescribe certain radiation safety training topics. Table 11.1 illustrates the common topics required by the radiation control authority in Texas. In reviewing Table 11.1, these topics may be considered rather general and not specific to the laboratory setting. Most laboratory directors will require significantly more detailed treatment of occupa- tional hazards in order to prevent hazardous exposures in the laboratory setting. Radiation protection standards require the level or duration of training be com- mensurate with the level of hazard presented by the radiation source. Laboratory safety training also commonly uses “dry run” walk-throughs and continual feed- back from the laboratory director. The “dry run” method of training enables a laboratory worker to progress stepwise through a new laboratory protocol without the inclusion of radioactive material. Laboratory workers may then plan out details such as the physical layout of the laboratory bench, placement of portable shielding, critical equipment, and radioactive waste containers. This important training initiative generally results in lower radiation doses for new laboratory workers by minimizing the time around radiation sources and improving process knowledge. Workplace surveillance programs enable an unbiased observer to review the use, storage, and containment of radiation sources in the laboratory setting. These DK594X_book.fm Page 373 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC 374 Radionuclide Concentrations in Food and the Environment observations are then presented to the laboratory director in order to reduce radiation exposures in the laboratory. Workplace surveillance programs may be initiated by the laboratory director or the facility radiation safety personnel. A common approach involves the use of a published survey tool, removable con- tamination surveys, and an ambient radiation level survey. The survey tool or checklist enables a trained observer to evaluate the same laboratory situations in each facility laboratory. A further benefit of the survey tool is that the laboratory director or staff may periodically self-assess the safety of their program. Figure 11.2 provides an example of a common laboratory radiation safety survey tool. All radiation sources must have caution signs and hazard warnings denoting the presence of ionizing radiation in the workplace. This signage generally takes the form of the universal “trefoil” symbol with yellow background/magenta lettering or yellow background/black lettering. Figure 11.3 is an example of the common radiation trefoil symbol. 11.6 CONCLUSION Ionizing radiation presents an important risk to the general public and in many workplaces. The preventive measures described in the text outline prudent steps for eliminating or mitigating the hazard posed by these ionizing radiation sources. The comprehensive philosophy of anticipation, recognition, evaluation, and control of ionizing radiation sources yields a framework for the safe and healthful use of these sources. Further refinements in the risk factors, biological outcomes, uses, and tech- nology surrounding radiation exposure should be anticipated. New international recommendations for radiation protection are routinely revised and reissued. This process lends itself to pragmatic review of all operations with exposure to radi- ation hazards. Therefore the guidelines suggested throughout the text should be viewed as a current evaluation of the status, but continuous improvement, work practice controls, and engineering controls should be adopted. The use of potential carcinogens in the workplace places a heavy burden on the radiation protection program administrators because of the potential for seri- ous biological endpoints. A sensible approach to evaluating, mitigating, or elim- inating the risk to occupationally exposed individuals is critically important. These steps, taken in conjunction with standard laboratory practices, provide a solid foundation for engaging in the benefits of ionizing radiation while offsetting the negative outcomes. DK594X_book.fm Page 374 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC Radiation Protection Programs 375 FIGURE 11.2 Radioactive material laboratory safety evaluation survey tool. University of Texas-Houston health science center Environmental Health and Safety Department Radiation Safety Division Laboratory Safety Evaluation Record Date Performed:________________ Page: 1 Date Printed: 1/13/2006 Procedure: Evaluate each of the following items according to the requirements of the Radiation Safety Manual, June 1996. Place a check in the appropriate space for either Y (YES), N (NO), or N/A (Not Applicable). Enter comments in the provided space. YNN/A Comments? General Safety General housekeeping orderly? _______________________________ Current emergency contact phone numbers posted? _______________________________ Hazard communication training attendance? _______________________________ Linear air flow rate in hood adequate? _______________________________ Measured linear flow rate:____________lfpm Is the hood air flow laminar? _______________________________ No food or drink observed in laboratory? _______________________________ Fire Safety Fire egress unobstructed? _______________________________ Fire extinguisher available? _______________________________ Electrical circuit load appears normal? _______________________________ Physical Safety Absence of trip hazards? _______________________________ Compressed gas cylinders secured? _______________________________ Personal protective equipment used? _______________________________ Guards in place for mechanical hazards _______________________________ Biological Safety Biohazard laboratories properly posted? _______________________________ Universal precautions utilized? _______________________________ Biological safety cabinet certified (annual)? _______________________________ Ultraviolet lamps used properly & posted? _______________________________ Biohazard waste properly stored? _______________________________ Chemical Safety NFPA rating present? _______________________________ Chemicals stored properly? _______________________________ No flammables stored in refrigerator? _______________________________ Chemical waste properly stored? _______________________________ Radiation Safety Appropriate CRAM signs posted (door, hood, ref, etc.)? _______________________________ Properly documented lab survey records present? _______________________________ Wipe test equipment appropriate & functioning? _______________________________ Current Radiation Safety Manual available? _______________________________ Current NTE & emergency procedures posted? _______________________________ Radionuclide storage & security adequate? _______________________________ Personnel monitoring utilized and appropriate? _______________________________ Survey instrument available, calibrated, & functioning? _______________________________ Radioactive waste stored properly? _______________________________ No additional safety concerns? _______________________________ Any unsatisfactory safety condition or concern must be relayed to the appropriate Environmental Health & Safety Division Relayed To: Date: Concern(s): DK594X_book.fm Page 375 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC 376 Radionuclide Concentrations in Food and the Environment 11.7 SUPPLEMENTAL READING Charlton, M.A. and Emery, R.J., An analysis of reported incidents involving radiophar- maceuticals for the development of intervention strategies, Health Phys. , 81, 585, 2001. Emery, R.J., Adding value to your radiation protection program, in Management and Administration of Radiation Safety Programs , Roessler, C.E., ed., Medical Physics Publishing, Madison, WI, 1998. Emery, R.J., Charlton, M.A., and Goodman, G.R., Texas radiation protection program outcomes as indicated by regulatory compliance activities from 1988 to 1997, Health Phys. 78, 335, 2000. Emery, R.J., Charlton, M.A., and Mathis, J.L., Estimating the administrative costs of regulatory noncompliance: a pilot method for quantifying the value of prevention, Health Phys. , 78(5 suppl.), S40, 2000. Emery, R.J., Charlton, M.A., Orders, A.B., and Hernandez, M., Using fault tree analysis to identify causes of non-compliance: enhancing violation outcome data for the purposes of education and prevention. Health Phys . 80(suppl. 1), S16, 2001. Emery, R.J., Pollock, J., and Charlton, M.A., Notices of violation issued to Texas radio- active material licensees inspected in 1995, Health Phys. , 73, 706, 1997. Texas Department of Health, Texas regulations for the control of radiation, Bureau of Radiation Control, Austin, TX, 2002. U.S. Nuclear Regulatory Commission, Standards for protection against radiation, Title 10 CFR part 20, 1991. U.S. Nuclear Regulatory Commission, Uses of radioactive material, NUREG/BR-0217, U.S. Nuclear Regulatory Commission, Washington, DC, 1996. FIGURE 11.3 Common radiation trefoil symbol. The color version has magenta coloring on a yellow background. DK594X_book.fm Page 376 Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC . Radionuclide Concentrations in Food and the Environment 11. 7 SUPPLEMENTAL READING Charlton, M.A. and Emery, R.J., An analysis of reported incidents involving radiophar- maceuticals for the. those individuals in laboratories involved with the analysis of radioactivity in food and the environment. Sources of radiation inherent to these analytical processes and procedures include ionizing. outlined in this chapter. These hazards should warrant additional management systems beyond the scope of this chapter. Figure 11. 1 outlines a pragmatic schema for describing the overarching prin- ciples