DALT-T Certification

What the ICB Duct Air Leakage Testing Technician Credential Is

The Duct Air Leakage Testing Technician certification is issued by the International Certification Board (ICB). It validates that a technician understands how to plan, set up, run and document duct air leakage tests on air distribution systems. The test itself is a measurement discipline: you isolate a duct section or system, pressurize it, and quantify how much air escapes through seams, joints and penetrations. The credential confirms you can do that correctly and interpret the result against project requirements.

This page covers the certification itself: how it is structured, who can sit for it, how scheduling works and what keeps it active. If you are brand new to the acronym, our explainers on what DALT-T certification is and what DALT-T stands for cover the basics. This article assumes you already know you want the credential and need to understand how it works in practice.

Exam Format at a Glance

The exam is a proctored written examination. It can be delivered online or on paper at designated sites, and ICB-designated proctors administer it. You do not walk into a testing center on your own schedule; your local JATC coordinates the session.

Two details deserve attention. First, you will not know which eight items are the unscored beta questions, so treat every question as if it counts. Second, the 25-correct threshold is applied to the 32 scored items, which leaves a defined margin for error. For a deeper look at the threshold, see our breakdown of the DALT-T passing score.

The 2.5-hour duration comes from the ICB Certification Exam Details document (Version 2.6) hosted by providers such as the Southern California Sheet Metal JATC. It reflects the written exam only. It is not a measure of course hours and does not include any practical assessment. Given 40 questions, you have roughly three and a half minutes per question on average, which is comfortable for recall items and tight for multi-step calculations you work by hand.

Eligibility and Approval Before Testing

ICB approval comes first. You apply, ICB reviews your eligibility, and only after approval can you be scheduled. Under Section 3.2 of the Certification Manual, eligibility runs through technician categories that are alternatives, not cumulative requirements. You need to fit one of them:

• Eligibility tied to NEMIC contribution status
• Qualifying work under SMART collective bargaining
• Specified circumstances of temporary unemployment or disability
• Temporary employment in sheet metal organizing

Once approved, the clock starts: the written examination must be completed within one year of application approval. Let that window lapse and you would need to go back through the approval process. Build your preparation timeline backward from that deadline rather than treating approval as the starting gun for casual study. Our DALT-T requirements guide walks through the eligibility categories in more detail.

The Seven Domains and What They Demand

The exam draws on seven weighted knowledge-base headings. These are the official domain lines, and the weights tell you where the question volume concentrates. The full walkthrough lives in our DALT-T exam domains guide; here is the practical view.

Why Fluid Flow and Instrumentation Deserve Your Early Attention

Fluid Flow (22%) and Instrumentation (18%) combine for 40% of the knowledge base. With 32 scored items, that translates to a large share of the questions you will actually be graded on, though ICB does not publish how many questions come from each domain on a given form, so treat the weights as a guide to emphasis rather than an exact count.

Scheduling, Proctoring and Retest Waits

Scheduling runs through the local JATC, not through a general-purpose public testing portal. ICB's technician instructions direct candidates to the local JATC for training and for access to the ITI study manual. In practical terms, your JATC is both your training pathway and your testing coordinator.

The sequence looks like this:

1. Confirm which Section 3.2 eligibility category applies to you
2. Submit your application and wait for ICB approval
3. Coordinate with your local JATC on training and a proctored session
4. Sit the written exam within one year of approval

If you do not pass, mandatory waiting periods apply before you can retest:

The escalating waits are a good reason to prepare thoroughly for the first attempt. Each failed attempt does not just cost time; it lengthens the next wait. For scheduling specifics and how to plan around deadlines, see our DALT-T exam dates guide.

Working With Approved Reference Materials

This exam allows candidates to consult approved reference materials, including on computers, tablets or smartphones. That is unusual enough to change how you should prepare. Communication with others and capturing or copying exam content are prohibited.

Do not mistake permitted references for a substitute for knowledge. With a 2.5-hour limit and 40 questions, flipping through a manual for every item will burn your time. The realistic use of references is verification: confirming a formula, a table value or a specific requirement you already roughly know. Candidates who know where things are in their approved materials, and who have practiced finding them quickly, get the benefit. Candidates who rely on looking everything up tend to run short on time.

Staying Certified: Renewal and CEUs

Certification is valid for two full years from the last day of the quarter in which you obtained it. That quarter-end rule means your actual expiration date can be a bit later than a simple two-year count from the exam date.

Renewal under the ICB manual (Sections 3.8 and 3.13-3.14) requires three things:

• Continued eligibility
• An application submitted before your certification expires
• Four acceptable ICB CEUs earned during the certification period

One training hour equals one ICB CEU. Four total acceptable CEUs renew all technician certifications you hold, so if you carry more than one ICB technician credential, the same four CEUs cover them together rather than requiring four per credential.

A Domain-Ordered Study Sequence

Rather than generic scheduling advice, order your study by how the domains depend on each other. Math underlies everything, Fluid Flow explains the physics, Instrumentation puts physics into equipment, and the procedure domains apply all of it. A sample ordering for a six-week plan, adjustable to your own timeline and JATC coursework:

For a fuller methodology, see our DALT-T study guide, and if you are weighing your readiness, how hard the DALT-T exam is offers a candid look at where candidates struggle. When you are ready to test yourself, our practice test platform lets you drill by domain.

Where the Credential Fits in a Career

The certification is built for the sheet metal trades. Because the eligibility categories center on NEMIC contribution status, SMART collective-bargaining work and sheet metal organizing, the credential naturally serves technicians working in or alongside the union sheet metal industry. Employers there include signatory sheet metal contractors, test-and-balance and commissioning-related firms working with air distribution systems, and others who need documented evidence that duct leakage testing was done by a qualified person.

Whether the credential pays off for you depends on your market and employer, so we avoid quoting earnings figures here. Our DALT-T salary guide and analysis of whether the certification is worth it discuss how to evaluate the return qualitatively, and DALT-T jobs covers the roles where the credential tends to matter. If you want training details, see DALT-T training.

Frequently Asked Questions