Hi Aniston,
I am licensed in eight jurisdictions on the East Coast, having taken the civil/structural PE and 16-hour SE exams. Also, since I operate my own practice, I have to make decisions about where I am licensed and the conditions under which I am in responsible charge of projects (generally, sealing a document is the public-facing evidence of being legally in responsible charge for a project). Licensing laws, regulations and guidelines can vary greatly from state to state and change over time. Universally, you cannot be in responsible charge for services outside your area of competence. That transcends discipline; if you are not competent to provide a particular service in your discipline, you must become competent, work with others as permitted by law, or refrain from providing that service.
The licensing laws of most jurisdictions do not confer different privileges on licensees of different disciplines. Some states will list your discipline on your license and/or seal, but that typically does not affect what you can seal. Consequently, there are plenty of civil engineers, architectural engineers, etc. (by exam/license) engaged in structural engineering and related fields like construction engineering, geostructural engineering and building envelope consulting. It is competence in one's specialty area that is more relevant than the specific discipline of licensing. That said, there can be weird counterexamples. In Vermont, the practice guidelines (as opposed to the laws and regs) prohibit incidental practice outside one's licensing discipline of licensing without definitions of each discipline. Therefore, as a structural engineer, I might or might not be able to include some incidental civil engineering item on my plans or issue a geotechnical report despite having the experience and being licensed as a civil engineer in neighboring states. I have never heard of this guideline being enforced and I am not convinced it is lawful.
Things get more complicated in the "title act" states, mostly in the West, where a structural engineering license confers some additional privileges but is not required for every project. I have not looked at California's licensing requirements recently, but it used to allow someone to become a civil engineer with two years of experience after passing the NCEES exam and state-specific seismic and survey exams. A civil engineer is primarily prohibited from being The restriction on PEs performing structural engineering varies by state. Typically structural engineering for buildings is restricted on the basis of size or importance. I think there may be one or two western states that require that licensed structural engineers design long-span bridges.
Also, in my experience, it is common on infrastructure projects for one senior engineer to seal all of a firm's drawings and specifications for the project regardless of discipline. Depending on how a jurisdiction defines responsible charge and the procedure within the firm, this practice may violate the spirit, if not the letter, of licensing regulations. It can also look ridiculous, like the guide sign package I once saw for a highway tunnel project in Massachusetts sealed by the structural engineer who likely oversaw the design of the sign structures. The guidance included things like "I-90 West, Worcester, Seatle" and was mocked by traffic engineers in other parts of the project.
I presume that you are still a few years away from being licensed. In that case, your early employment may push you into a specialty where a particular strategy for licensing becomes apparent. The structural engineering exam is challenging for someone who is not regularly engaged in building or bridge design early in their career. I started my career as a structural engineer in a geotechnical firm, mostly designing temporary structures. I felt that the civil/geotechnical syllabus seemed ambiguous, so I went with the structural depth section. I understand that similarly situated engineers today often take the construction depth section.
When I apply for licensing in a new state, I use my structural engineering credentials. Other than Vermont, I have not found that to be a limitation. Therefore, if you know you want to do structural engineering, and your early experience is relevant to the SE exam, you would probably be OK starting there. If you moved into an adjacent field, you would still have a license that would be relevant enough once you are competent in the new field. That said, I think there is value in becoming a PE, passing the civil/structural exam or otherwise as soon as possible, and using that experience as a step towards preparing for the SE exam. Firms often reward licensing, and it is unquestionably a resume booster.
If the civil/structural exam will not get you licensed in Illinois, you might be able to take the civil/transportation or civil/construction exams. Your education and early experience will influence how practical that would be. You can check out the civil exam syllabi here: Civil | NCEES. Keep in mind that you can take exams in different states and do not have to take the exam where you live. I was initially licensed in New York, where I lived and worked, but had several coworkers take the PE in other states due to particular provisions of New York licensing law relating to immigration status. You could initially become a PE in another state and become an Illinois SE later. You might even be able to take the civil/structural in Illinois and use it to become licensed in another state.
In closing, I will note that the NCEES exams are not that well aligned with what you learned in school or real-life practice, especially if you end up in a specialty drawing from multiple (sub)disciplines. The exams set a baseline for entering practice but do not by themselves make you qualified to do anything in particular. You likely will not be asked to be in responsible charge of something until after you have been licensed for at least a few years. While it is good that you are thinking about this now (take the FE ASAP if you haven't already), you will have options when the time comes and the right option may not be apparent until you are closer to applying for your initial license.
I hope this helps, and best of luck.
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Richard J. Driscoll P.E., M.ASCE
Lebanon NH
rjd@...[Phone]
www.richardjdriscoll.com------------------------------