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A Rain of Glass — The Day a Fluorescent Light Broke at My Vertical Farm

Imamura here. Before LED lighting became the standard, even just replacing a fluorescent tube at a vertical farm was a job you had to handle with care.

Back When It Was Fluorescent Lights

These days, LED lighting is the norm in vertical farms. Surveys suggest more than 90% of PFALs have adopted LEDs.

But a while back, the vertical farm where I worked ran on fluorescent tubes. Those long, narrow cylinders. They had a look about them that just said “ready to shatter” — and honestly, every time I worked near one, I braced myself a little.

Inside the facility, tens of thousands of fluorescent tubes were lined up in neat rows. Morning inspections started with finding the ones that had burned out.

“Three more dead today.”

Spotting them was one thing — but the inspection itself was exhausting work. Workers would walk back and forth along every grow bed, end to end, dozens of times. Staring at bright lights up close for that long, you’d start to feel your vision flickering after about fifteen minutes.

After a few hours, your memory starts to slip a bit.

“Wait — did I already check this bed?”

I found myself in a state that felt a bit like mild amnesia — genuinely unable to remember whether I’d checked a particular bed. I actually wondered if too much light exposure was slowly dissolving my brain.

And the postures involved in checking the lowest and highest beds were rough. Twisting your lower back, bending your neck ninety degrees, craning to peer underneath.

“Let’s start the morning with yoga — fluorescent-light downward-facing pose.”

That kind of joke was how we got through the daily inspections.

The Replacement Job

Once you found a burned-out tube, the next step was replacing it.

That part was nerve-racking too. When removing a fluorescent tube, you’d sometimes hear a sharp squeaking creak — the kind that makes you wonder if the glass just fractured. Every time: hands freeze, stomach drops — “did it crack?” Even if removal went smoothly, the snap of the new tube locking into place was enough to spike the heart rate again.

When a replacement went without incident, the relief was genuine. You’d replaced one fluorescent tube and somehow felt like you’d just finished something significant.

That was the daily routine — until the day one finally broke.

The fluorescent tube replacement that day was assigned to Tanaka (name changed), a new hire.

“Be careful — if it breaks, it’s a serious situation.”

Those words had just left my mouth.

“Aahh—”

That short sound and the crash of shattering glass arrived almost simultaneously. Inside the vertical farm, that sound alone rang out with strange clarity. I remember the ambient work noises fading for a moment, every person freezing in place.

The tube had slipped from Tanaka’s hands, struck the edge of a grow bed before reaching the floor, and shattered into fragments.

A few seconds, I think. But those few seconds felt extremely long. Broken. Where did it fly. What’s below. Lettuce. Shipment. Stop everything. My head was spinning with nothing but fragments.

Tanaka’s face went pale — visibly, rapidly pale. And no wonder. The fluorescent tube had broken directly above the lettuce that was still in production.

The Disposal Decision

Glass fragments had scattered across the surrounding beds. The moment I saw it, I knew this wasn’t a situation you resolved by picking up the pieces.

Tanaka quietly murmured, “What do we do?” I remember that voice sounding very small. It must have hit him hard.

We contacted our supervisor immediately. After that, at the supervisor’s call, an emergency response meeting was convened.

The problem was simple.

“If produce with glass fragments attached got shipped—”

That one sentence froze every face in the room. Glass contamination was absolutely not something that could happen. No matter how carefully you checked, you couldn’t eliminate the possibility that fine fragments remained.

The final decision: discard all crops in the grow beds where glass fragments may have reached.

A single broken fluorescent tube, and dozens of beds’ worth of crops were gone. Stated as a number it sounds dry, but standing in that facility looking at the affected area, I felt a heaviness in my gut. Even now as I write this, the sound of that shattering glass, and the image of small, whitish fragments glinting in the light, stay with me.

Since Switching to LED

A few years after that incident, the facility where I was working replaced all its lighting with LEDs.

Lamp replacement work after the LED conversion was genuinely easier. At the very least, there’s no longer the terror of that fluorescent “crack.” Being freed from work that put me on edge every single time — that was significant.

These days, when I mention in new-hire training that “we used to use fluorescent tubes,” the younger staff respond with a polite “oh, sounds like it was rough” — more or less the way you’d react to someone else’s problem.

That reaction is correct. It’s not hardship they need to know.

Even so, sometimes as I walk through the facility, I remember the sound of that glass shattering. I never expected a vertical farm to give me fluorescent-light trauma.

Every time I walk beneath the quiet, safe LED lighting, I think the same thing.

Switching to LED was genuinely one of the best things that happened.