Pipefitters, also known as steamfitters, install pipes in new or existing buildings, hospitals, industrial plants and other facilities. They learn their trade through 5-year apprenticeships that include both classroom instruction and on-the-job training, but must pass an apprentice exam to be eligible for the program. Ideal candidates are knowledgeable about welding processes for piping systems and about both power and hand tools. Those who excel in drafting, blueprint reading, mechanical drawing, physical science and mathematics should have the best prospects.

Ensure You're Eligible

According to the California Apprenticeship Coordinators Association, applicants must be able to read, speak and write in English, as well as furnish proof of their legal right to work in the U.S., such as a birth certificate. To take the exam, candidates need to be at least 18 years old and possess a high school diploma or the equivalent and a valid driver’s license. Depending on the program, applicants may also need transcripts showing mathematics grades of a “C” or better.

Take the Written Portion

The written portion is the primary component of the apprentice exam. Every exam focuses on math, including converting percentages to decimals and adding, subtracting, multiplying and dividing fractions. Additional content and the passing score, though, vary by program. For example, Local 343, the pipefitters program for Solano and Napa counties, requires candidates to complete spatial relations and mechanical aptitude portions. Although the passing score varies, most require a minimum of between 65 and 75 percent.

Ace the Interview

Candidates who successfully complete the written exam are scheduled for an oral interview. The California pipefitters programs don’t disclose the information discussed in oral interviews, but applicants can expect a general assessment of their personality traits, goals and experience. In some programs, the oral interview is the last step, and candidates’ scores are determined by combining the two components. For other programs, candidates who pass the oral interview are then sent for drug and alcohol screenings.

Make the List

Following most pipefitters apprentice exams in California, applicants are ranked and listed in order of their final scores, from highest to lowest. Apprenticeship programs take the top names off the list until all spots are filled. According to Steam-Refrigeration-Air Conditioning-Pipefitters Local Union 250, any candidate on the list that doesn't make it into a program must complete the entire application and examination procedure again for the next round.