Geodetic Surveyor Certification and/or Professional Registration
Herbert W. Stoughton, Geodetic Engineer
Definitions
Geodesy: The science which treats mathematically the figure, form, and size of the earth.
Geodetic Surveying: Is that branch of surveying which takes into account the size and shape of the earth. Geodetic surveying addresses the three dimensional aspects of the world (curvature of the earth) and four dimensional aspects of the points in the space–time continuum. Sophisticated instrumentation and procedures are employed in order to attain specific accuracies and precisions. Also, advanced and sophisticated computing techniques are required. Geodetic surveying may require knowledge and training in aspects of physical, engineering, and geophysical sciences in order to complete assignments.
The Problem
Geodetic surveying requires an in depth knowledge of topics in the subjects of mathematics; statistics; engineering, geophysical and physical sciences; metrology; and surveying. As more precise and accurate surveys are required, physical phenomena that have been disregarded in plane surveying work can significantly impact survey observations and data. Geodetic survey data are at least one order of magnitude more precise. Observing and data reduction procedures are more sophisticated and complex, and require more exacting attention to details. An in depth knowledge and understanding of systematic errors, their detection and identification, and their removal from the data are paramount for a broad spectrum of engineering, geophysical, political, navigational, legal, commercial, and national defense programs requiring the information. In order to address these programs’ needs, the geodetic surveyor must have excellent communication skills in order to be able to converse with the end-user and understand the latter’s needs. A poorly designed geodetic survey could provide no information or misinformation.
Failure to understand and apply geodetic surveying correctly in engineering projects has resulted in major misalignments in highway and tunnel construction; gross errors in water line and sewer construction; errors in building’s structural layout; incorrect building and dam deformation information; and invalid subsidence studies. In these instances, the problems were caused by faulty survey procedures, data reduction, data adjustment, or post processing analysis. The failure to comprehend the environmental effects on survey observations and recognize their contributions to final data integrity causes serious problems.
One of the most critical technological problems which has continuously plagued geodetic surveying has been the lack of understanding about datums and their physical and geometrical interrelationships. There are very few definitive writings on the subject, and these have little circulation. Because of the recent impact that GPS surveying has on surveying and mapping, the subject of datum transformations must be addressed.
Scope of Technical Practice
The scope of geodetic surveying is limited only by the problem assignment. Although there is a significant diversity in geodetic surveying, a number of the activities and functions are broadly applicable. Geodetic surveying generally is associated with highly accurate and precise surveying methodology to establish horizontal and vertical geodetic networks. While this philosophy is valid, geodetic surveying is the art and practice of developing survey control sufficiently accurate and precise to accommodate and address the requirements for the project or program.
Technical practice requires defining the problem, designing the survey, executing the data collection, reducing and adjusting the observations, and analyzing and publishing the results. The practitioner may be proficient in one or more of these areas, but should have familiarity with the goals and objectives of all phases of a geodetic survey.
If we list the various geodetic survey types in order of use and importance, we shall discover a preponderance of the effort is directed to about four types of surveys, and less than twenty percent of the total effort being expended on the remainder. The four types are horizontal control (conventional triangulation, trilateration, and traverse); vertical control (conventional differential and trigonometrical leveling, geometric and geopotential heighting), Global Positioning System (GPS), and gravimetry. Many individuals would argue that gravimetry is not a major effort, but it must be remembered that approximately eighty percent of all gravimetric surveys are performed for geophysical exploration, and the remainder of the surveys support Department of Defense weapon systems, inertial navigation systems, and national geodetic vertical networks.
The “smaller” activities include astronomic azimuth determination (stellar, solar, and gyroscopic/inertial), astronomic positioning, Very Long Baseline Interferometry (VLBI), geomagnetic mapping (high accuracy mapping), analytical photogrammetry, and miscellaneous space techniques and campaigns (i.e. lunar laser ranging).
Personnel Requirements – Education
An individual who is a geodesist or geodetic surveyor requires post secondary education and suitable experience. As a starting point of reference, let us accept the U.S. Office of Personnel Management’s minimum education criteria for entry-level geodesist – thirty (30) semester hours or forty-five (45) quarter hours of post secondary education in mathematics (analytical geometry, differential and integral calculus, statistics, etc.); physical, engineering, and geophysical sciences; and surveying (or surveying related subjects). These subjects must be taken and passed at a regionally or nationally accredited academic institution, or through the SAT Advance Placement examination, or other recognized and accepted testing authority. If courses are completed through correspondence, then criteria must be written which stipulate minimum qualifications by the offering institution. This latter requirement is intended to eliminate those "academic" institutions offering "bogus" degrees.
In addition to the aforesaid academic course work, satisfactory short courses and seminars may be included to satisfy academic requirements. However, in order to accept such latter academic experience, the certifying organization must develop and implement a fair and impartial set of guide lines addressing minimum course content, contact hours, assignments, syllabus and course outline, instructor qualifications, and evaluation of student comprehension. This type of course should not be a “survey” course for nonprofessionals, but a technical presentation of bona fide information.
Personnel Requirements – Experience
Minimum education qualifications are only an entry-level requirement. Good technical experience provides the knowledge that makes the professional. The committee evaluating the experience must address a subjective aspect of the certification/professional registration process. When an applicant submits experience, the evaluator must determine if the experience was: (1) professional and meaningful; (2) progressively more demanding; (3) the same experience for a short period of time repeated many times; and (4) indicates an increased technical/professional responsibilities with follow-on projects.
The evaluation of experience shall not
be a "bean counting" endeavor, but a meaningful interpretation of the applicant’s efforts. When this philosophy is employed, then it is the applicant’s responsibility to concisely and accurately describe the experience and demonstrate an understanding of the intent of imparting information to the evaluator. It also is the duty of any references to certify as to the accuracy and validity of the applicant’s described experience.
Examination
The final evaluation of an applicant is a professional examination. This examination can only be prepared from the topics that are contained in an approved and published syllabus or “Scope of Technical Practice”. The distribution of topics shall be in the same proportion as the distribution of the sub disciplines discussed in “Scope of Technical Practice”. It is recommended that some questions be mandatory and the remainder be chosen from a group of questions (i.e. questions on conventional control surveying, GPS, and geodetic adjustments be mandatory).
In order to have an impartial evaluation of the examinee, each question should require the examinee to: (1) define the problem; (2) identify the factors and conditions that could untowardly affect the solution; (3) offer a technically and economically feasible solution; and (4) defend the proposed approach. This format of examination means that it is graded/evaluated “subjectively” rather than “objectively”. This approach means time consuming evaluation which must be defendable from judicial litigation. This matter can be satisfactorily addressed. In general, the “objective” examination employs the ‘multiple choice’, short answer, true/false, and multiple choice examinee response. Since the evaluation of the applicant’s knowledge requires an in depth knowledge base, an objective examination does not provide a meaningful analysis tool.
When an examination question is submitted, the question writer must submit a detailed solution (or multiple solutions/alternatives). These questions and answers are retained in the data base. When an examination grader discovers another logical and/or feasible approach (which does occur), this new solution is added to the file. The examination grader must realize that some questions do not have a single unique answer, but may have several reasonable answers. It is recommended that multiple graders be employed on each examination to mitigate any charges of bias in evaluating the submitted examination solution.
The most important aspect about the examination is the educational value derived. A properly designed examination will provide information to the grader concerning the knowledge possessed by the examinee, and can provide insight into the examinee’s ability to address technical problems and provide reasonable solutions. It is important that the examination provide both types of information.
Concluding Remarks
It is imperative that certification/professional registration not be identified as an alternative to the statutorily professional licensure/registration by states. Some states only address the practice of land surveying, but other states require professional licensure either as a professional land surveyor or a professional engineer to perform geodetic surveys. There is a definite place and role for geodetic certification/professional registration, but its acceptance is only viable if the sponsoring organization carefully defines the program and its implementation.
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Herbert W. Stoughton, Ph.D., P.E., P.L.S., C.P.
Geodetic Engineer
5 February 2011