Chapter 2 — The City Has No Smell

The Urban Sensory Center's odor testing room has no windows. The four walls are covered with rough white material, the floor has drainage ditches, and the ventilation system runs independently of the building. Every morning, Huyen checks the tightness of the sample trays with a thin paper towel. If the towel moves too much, she must stop the test session. Participants may forget a number, but they must not be placed in an unprepared room.

The next day the paper was blank, the council had twelve people. They work in many occupations: teachers, packaging workers, kitchen staff, students, retirees. No one can be called a “standard nose”. They are just people trained to describe feelings on the same scale. Huyen always reminds that before starting.

“You don't need to guess what the substance is,” she said. "Just say you feel the intensity, nature, duration and level of discomfort. If you don't feel it, write down that you don't notice it. Don't try to find it."

A woman named Diem asked: "If you smell it but don't feel uncomfortable, what should you write down?"

"Write down both. The smell can be strong without being unpleasant. The smell can be weak but makes people nauseous."

That day they tested three air samples taken from the Nam Ben area. Sample A received before station number 3 started. Sample B received after spraying. Form C was received in an alley four hundred meters from the station. Huyen did not tell the committee the order, just put a code on the bag.

Sample A caused eight people to recognize the smell of organic mud and three people additionally described the smell of old oil. Sample B was reported by six people as "not noticed", four people reported a feeling of dryness in the throat, two people were not sure. Model C has almost no description, but Diem notes “the head feels a bit heavy after twenty seconds”.

Huyen looked at the results table. No number is enough to conclude that sample B is dangerous. There was also no reason to delete Diem's note.

At that moment, the sound of the ventilation fan changed. A layer of cold air blew through the room. Outside, the Clean Layer system starts the spray cycle seven minutes ahead of schedule. Sample trays must be closed. The council wouldn't have known that if Huyen hadn't seen the indicator light on the secondary screen.

“Stop,” she said.

The technician in charge looked up. “The model is not finished yet.”

“Room conditions have changed.”

“Just ventilation.”

Huyen pointed to the time column. "We are measuring the ability to perceive. If the external environment has just had a spray, the results after that are no longer compared to the previous results."

The person in charge calls operations. A male voice answered through the loudspeaker: "The schedule has been synchronized. The station did not spray early."

Huyen asked to see the system time. Tung appeared ten minutes later, taking off his helmet right outside the door so as not to bring the smell of oil into the room. He looked at the control screen, then at the test board.

“Station 3 ran a calibration cycle,” he said.

“Not on the calendar.”

“Automatic corrections do not appear in the public calendar.”

“So the council just tried it in a condition they didn't know about.”

Tung did not respond immediately. He opened the tablet log, scrolling to the line at 0943. A sensor reported deviation, the system went into a short neutral cycle. No problems. Just a technical activity considered too small to report.

“How much solution?” Huyen asked.

“Forty-two percent capacity in three minutes.”

“So why didn't six people notice sample B?”

“Sample B taken before this cycle started.”

Huyen looked at him. “Are you sure?”

Tung gave the station schedule. “I'll definitely follow machine hours. If you want to compare the sample collection time, you have to ask the person who took the sample.”

The sampler was a young employee standing in the hallway. He remembers picking up bag A at 0912, bag B at 0935, bag C at 1002. The spray system calibrated at 0943. So sample B was actually picked up first, but could have been in the shipping box when the spraying started. The box is not completely sealed; it is designed to maintain thermal conditions, not to prevent any substances from evaporating.

Huyen notes rather than concludes: “The sampling sequence is not sufficient to separate the time of collection from the time of exposure.”

Tung read that line. “Do you know that a sentence like that makes it difficult for a report to be accepted?”

“I know that an easy-to-read sentence can mislead others.”

At noon, the council left the room. Diem stayed behind to sign the appendix because she wanted to keep the heavy note intact. She asked Huyen if it was her imagination.

“I don't know,” Huyen said. “But we recorded it so we can check next time.”

“What if next time I don't have a heavy head?”

“That was also the result.”

In the afternoon, Huyen and Tung went to station number 3. The station was located behind the fence of the warehouse, next to the road leading to the school. The nozzles create a thin mist that does not fall to the ground but dissipates at the height of the roof. Tung opened the control cabinet and showed her each part: main pump, auxiliary pump, flow sensor, calibration box, exhaust valve.

“The Clean Class doesn't measure all substances in the air,” he said. “It only responds to the group of molecules that the sensor is trained to recognize.”

“So does he know what he doesn't know?”

“The machine doesn't use that expression.”

“Human beings must use it.”

Tung opened the maintenance panel. There are lines marked in yellow: slight drift sensor, compensated; slow release valve, monitoring; Calibration box waiting to be replaced. Huyen asked how long it would take for the box to be replaced.

“Three months.”

“Why is there no public calendar?”

“The public calendar states the station status. Not talking about each spare part.”

“What if the accessory changes the outcome?”

“It must be recorded in the technical file.”

“I want to see the file.”

Tung locks the screen. “What do you want to see?”

“The odor examiner is investigating a complaint from the school.”

“The investigation sounds like there was a crime.”

“So it's called evaluation.”

“The name doesn't make the maintainer less to blame.”

Huyen looked at the valve light. “I don't want to blame. I want to know when the city says there is no smell, what did the system do to make that statement true.”

Tung reopened the screen. “I will send the relevant diary. But she also had to credit the Clean Class for reducing odors for the people living here. My mother has been able to sleep since the station started.”

“I will write it down.”

“It's not for credit.”

“I write according to the data.”

He laughed, neither happy nor annoyed. “You are truly a member of the testing room.”

On the way home, Huyen stopped by Ben Reu market because of an address on the feedback list. The smell there is almost non-existent, but the fish sauce jars in the counter are still bubbling, the glass lids condensing. An elderly woman was arguing with the orderly about the "area needing deodorization" sign.

“What smell does this market have that needs to be eliminated?” she asked.

The employee pointed to the handheld screen. “Excessive discomfort index.”

“What smell?”

He couldn't answer.

Huyen stood at the entrance, looking at the jars of red-brown fish sauce lined up. The counter lady turned to her.

“Are you from the center? If they want to remove the smell, tell them not to erase the way we know the fish has gone bad.”

Huyen asked her name.

"Do Nghi. But let's call each other Nghi. In this market, no one calls each other by their full names when selling goods."

Nghi took a cloth and wiped the jar lid. "Come early tomorrow. I'll tell you which smell turns into money and which smell turns into illness."

Huyen wrote down the counter address in the book. In the bag, the white paper was still there. On the school grounds, An couldn't smell anything. In the tasting room, the panel disagreed. At the market, the fish sauce seller is being asked to apologize for the smell that no one can pinpoint.

The Reed River has not only lost its smell. It's taking language to ask who the smell belongs to.

Huyen returned to the testing room after Tung left. She asked the person in charge to turn back the ventilation log and mark the exact minute the correction cycle had intervened in the test. A colleague said there was no need because the results were disqualified. Huyen said the disqualification result requires even more reasons, otherwise a few months later someone will use the summary to say that the council has tried and found nothing.

Diem went back to get her bag. She looked at the sample board and asked if she could change the note "head is a bit heavy" to "mild discomfort".

"Why?" Huyen asked.

"A heavy head sounds like an illness. I just feel like someone put a damp cloth on my forehead."

Huyen gave her three different descriptions, not forcing her to choose one. Diem chose "forehead pressure, appears after about twenty seconds, reduces after going out". Huyen edited the sample label, keeping the original words in the change history section.

The technical person in charge walked by and asked Huyen if he was going to redo the entire test session. She said yes, but this time she would appoint one person to record the spraying schedule, one person to monitor room conditions, and one person to only record inconclusive things. The three of them looked at her as if it was a waste of manpower.

“If we don't do that, we'll just have a faster license plate,” Huyen said. “There is no more correct table.”

In the evening, she sent an update to Quynh and Tung. Tung responded with a file of the station's actual schedule, including automatic cycles not shown on the public portal. Quynh wrote that those cycles will be included in the public section after checking the presentation. Huyen realized that the system had begun to change not by a big decision, but by the pull in of a row that was once outside the table.

Before locking the room, Huyen sniffed the three control bottles again. She still recognized orange peels, damp soil, and solvents. But now she adds recovery time between samples. The nose needs a rest, just like a council needs to know when conditions have changed. She turned off the light, put a blank piece of paper in the file box, next to a new question: "If the smell belongs to more than one person, who gets to name it first?"