USC

A Leaking Liquid-Nitrogen Tank Draws Hazmat to the Seaver Science Center

Thursday, August 28, 2025CAhazmatemergency notificationmedium confidence

A bulk liquid-nitrogen tank began leaking outside the Frank R. Seaver Science Center at USC's University Park Campus around midday on August 28, 2025, drawing a Los Angeles Fire Department hazmat response. No injuries were reported, and the LAFD logged the call as a hazardous-materials incident at 920 Bloom Walk before crews secured the tank.

Alerts: 2
Response: —
Killed: —
Injured: —

Institution

University of Southern California

Private R1 · CA

TrojansAlert

Confirmed Timeline

Alert Sequence

2 messages in sequence · 1 verified verbatim

Some alert texts below are approximate reconstructions from news coverage, not confirmed verbatim transcripts. Reconstructed texts are shown in italic with a dashed border. Verified verbatim texts have a solid border and are marked accordingly.

INITIAL ALERTmulti-channelAround 12:15 PM PDT on August 28, 2025, shortly after the leak was reported

Approximate reconstruction134 chars

Hazardous materials incident reported at Frank R. Seaver Science Center at UPC. Avoid the area while crews respond. Updates to follow.

This text has been reconstructed from news coverage and may not reflect the exact original wording.

Reconstructed paraphrase: local outlets reported USC told the community to avoid the area as a precaution while LAFD and USC hazmat crews responded, but no outlet published the verbatim TrojansAlert text.

The leak was a bulk liquid-nitrogen tank, an asphyxiation and cold-burn hazard in confined spaces rather than a toxic release, which shaped the 'avoid the area' framing.

ALL CLEARmulti-channelEarly afternoon on August 28, 2025, after crews secured the tank around 12:35 PM PDT

Verified verbatimUSC statement quoted by CBS Los Angeles135 chars

The hazardous materials incident at Frank R. Seaver Science Center at UPC has concluded. University operations have returned to normal.

CBS Los Angeles quoted this USC statement word-for-word as the all-clear; it explicitly lifts the precaution by saying operations 'returned to normal.'

The all-clear came the same afternoon because liquid nitrogen disperses as a harmless gas once the leak is stopped and the space is ventilated.

Context

Background

Liquid nitrogen is a routine laboratory cryogen used for cooling and sample storage, but a leaking bulk tank can displace oxygen and cause cold burns, which is why a leak at a busy science building draws a full hazmat response. On August 28, 2025, a bulk liquid-nitrogen tank sprang a leak near the Frank R. Seaver Science Center at 920 Bloom Walk on USC's University Park Campus. The Los Angeles Fire Department logged the hazardous-materials call and dispatched a hazmat assignment; CBS Los Angeles reported that firefighters ultimately determined the leak posed no danger and that USC said operations had returned to normal. No injuries were reported in any account.

Analysis

Key Findings

A leaking bulk liquid-nitrogen tank — a cryogen, not a toxic chemical — was enough to trigger a full LAFD hazmat response and an avoid-the-area advisory at a major research campus

Crews secured the tank within roughly 35 minutes of the reported leak and issued an all-clear the same afternoon

No injuries were reported; the hazard was potential oxygen displacement and cold contact rather than poisoning

Outcome

Fire crews and USC's own hazardous-materials team secured the leaking tank within roughly 35 minutes. No one was injured and university operations returned to normal.

Provenance

Alert Sequence

Background

Key Findings

Sources

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