13.2 Punctuation, Comma Splices, and Parallel Structure

13.2 Punctuation, Comma Splices, and Parallel Structure

Quick answer: A comma splice is two complete checkpoint sentences joined by only a comma: "The traveler declined AIT, the officer offered a pat-down." Fix it with a period, a semicolon, or a comma plus and / but / so. A semicolon joins two closely related complete sentences; it is not a pause after a fragment such as "After the WTMD alarmed." Parallel structure keeps every item in a screening-step list in the same form: remove, place, wait — not remove, placing, and waiting. These are job skills for directions, SOP restatements, and incident notes. They are also the kind of English item legacy CBT write-ups describe. TSA does not currently publish English item counts for the TAB.

Punctuation on this job is not decoration. A missing period can merge two events. A broken list can send a traveler into the scanner with a laptop still in the bag. Write as if the next officer, the STSO, and the traveler all have to execute the sentence without asking you what you meant.

What a complete checkpoint sentence is

A complete sentence has a subject and a verb and can stand alone as a fact, a rule, or a command.

• Fact: The WTMD alarmed at 09:14.
• Rule: Travelers in a standard lane remove shoes.
• Command: Remove the laptop.

A fragment cannot stand alone as the record:

• After the WTMD alarmed.
• Which was found in the exterior pocket.
• Due to the fact that the image was unresolved.

Fragments belong attached to a complete sentence ("After the WTMD alarmed, the traveler returned to the podium.") or they should be rewritten as complete sentences ("The image was unresolved.").

Comma splices vs periods vs semicolons

A comma splice occurs when two complete sentences are joined by a comma and nothing else. Checkpoint notes produce splices because the writer is narrating two things that happened close together and reaches for a comma the way a speaker reaches for a breath.

Splice: The traveler declined AIT, the officer offered a pat-down. Splice: The X-ray operator called for a bag search, the traveler waited at the end of the belt. Splice: The folding knife is prohibited in carry-on, the traveler chose to exit with the item.

Each pair is two complete thoughts. A comma is not a legal joint.

Three legal repairs

1. Period. Use a period when the two facts can stand as two records. This is the default for incident notes.

• The traveler declined AIT. The officer offered a pat-down.
• The X-ray operator called for a bag search. The traveler waited at the end of the belt.

2. Semicolon. Use a semicolon when the two complete sentences are tightly related and you want them in one record line without a conjunction. Both sides must still be complete sentences.

• The folding knife is prohibited in carry-on; the traveler chose to exit the checkpoint with the item.
• The WTMD alarmed; the traveler returned to the podium.

3. Comma plus a coordinating conjunction. The common conjunctions in checkpoint writing are and, but, and so. The comma stays; the conjunction is what makes the joint legal.

• The traveler declined AIT, and the officer offered a pat-down.
• The folding knife is prohibited in carry-on, so the traveler exited the checkpoint with the item.
• The traveler stated the bottle was medicine, but the container still had to meet the published liquids process.

What a semicolon is not

Colon before a list. A colon follows a complete sentence and introduces the list. "The officer instructed the traveler to do three things: remove the laptop, place the quart bag in the bin, and wait at the scanner." Do not put a colon after to or after including if the sentence has not yet become complete.

Quoted passenger statements. Put the traveler's words in quotation marks. The surrounding sentence still needs a legal boundary. "The traveler stated, 'I already took everything out.' The traveler then walked toward the sterile area." Do not splice the quote onto the next action with a comma and no subject.

Parallel structure in screening-step lists

Parallel structure means every item in a list uses the same grammatical form. At a checkpoint, lists are how you give directions, how you restate an SOP, and how you record the steps you already took. If the form changes in the middle, the sequence becomes ambiguous.

Spoken passenger instructions (imperative, parallel):

• Remove the laptop. Place the quart bag in the bin. Wait at the scanner.
• Remove light outer garments. Place bulky clothing in the bin. Stand with feet apart and arms up.

Same list, one sentence: The officer instructed the traveler to remove the laptop, to place the quart bag in the bin, and to wait at the scanner.

You may drop the repeated to after the first item if every item stays a bare verb: to remove the laptop, place the quart bag in the bin, and wait at the scanner. You may not switch forms.

Broken parallelism:

• The officer instructed the traveler to remove the laptop, placing liquids in the bin, and wait at the scanner.
• Remove the laptop, liquids in the bin, and waiting for the officer.
• The SOP requires divesting electronics, liquids should be in the quart bag, and wait for the officer.

Those lists mix an infinitive (to remove), a participle (placing), a noun phrase (liquids in the bin), and a command (wait). A traveler can obey a mixed list in the wrong order. A teammate restating the SOP can skip a step that no longer looks like a step.

SOP restatement (present, parallel): In a standard lane, travelers remove shoes, remove belts, remove light jackets, remove laptops and other specified electronics, and remove the 3-1-1 bag. Typical PreCheck travelers leave shoes on, leave belts on, leave light jackets on, leave electronics in the bag, and leave 3-1-1 liquids in the bag. Keep remove with remove and leave with leave. Do not write "remove shoes, belts on, and leaving jackets."

Incident-note action lists (past, parallel): The officer called for a bag search, opened the backpack at the table, located a 4-inch folding knife in the interior pocket, notified the STSO, and directed the traveler to the exit with the item. Do not write "called for a bag search, opening the backpack, and the knife was located."

And / or in public rules. When a public TSA rule uses a list, keep the published items parallel in your restatement. "Laptops, tablets, e-readers, and handheld game consoles" are all nouns. Do not restate that list as "laptops, take out tablets, and e-readers should be binned."

Error / correction table: punctuation and parallelism

Worked checkpoint scenarios

Scenario A — AIT opt-out, two sentences. A traveler in a standard lane says "I never go through the scanner." Two complete events follow: the decline, and the alternative. Splice: "The traveler declined AIT, the officer offered a pat-down." Repair with a period if you are logging two steps, or with and if you want one compound sentence. Do not write "The traveler declined AIT; and the officer offered a pat-down."

Scenario B — Prohibited item and traveler choice. A 4-inch folding knife is found in carry-on. Public TSA rules treat most knives as carry-on no, checked yes. The note needs two related complete thoughts: the item is prohibited in the cabin; the traveler chose an outcome. Semicolon is useful here: "The folding knife is prohibited in carry-on; the traveler chose to exit the checkpoint with the item." A period is equally correct. A comma alone is not.

Scenario C — Coaching at divestiture. The officer has three actions for a standard-lane traveler. Parallel commands: "Remove the laptop. Place the quart bag in the bin. Wait at the scanner." If the officer instead says "Removing the laptop, liquids in the bin, and you will wait," the traveler may bin the liquids, keep the laptop, and walk. Parallel form is a security control, not a style preference.

Scenario D — SOP restatement on the radio. A teammate asks what a standard lane requires for electronics and liquids. Parallel present-tense restatement: "Travelers remove laptops, tablets, e-readers, and handheld game consoles, and they remove the quart bag of 3-1-1 liquids." Switching to "laptops out, liquids should be, and waiting" is how an SOP restatement mutates into unofficial procedure.

Scenario E — Quoted statement plus action. The traveler says "I already took everything out" and then walks toward the sterile area with an unresolved bag still on the belt. Log the quote as its own sentence. Log the movement as its own sentence. Do not splice them: "The traveler stated, 'I already took everything out,' the traveler walked toward the sterile area" is still two independent sentences with only a comma between the quote's close and the next subject if you drop the second subject, or a splice if you keep it. Two periods keep the access-control fact usable: the bag was not yet cleared; the traveler moved.

On a legacy English section, these items look like "choose the sentence that is correctly punctuated" or "choose the parallel list." On the floor, they look like a traveler who did the first step and skipped the third because the third step no longer sounded like a step. TSA does not publish how many punctuation items appear on a current TAB. The checkpoint still grades the sentence every time someone has to follow it.