Microsoft 365 outage leads to chlorine gas poisoning of 15 hotel guests

Fifteen guests at a hotel in Germany suffered from chlorine gas poisoning because of the recent Microsoft cloud services outage. The establishment had a maintenance safety system" for its sauna area that relied on sending emails to warn the operators if the chlorine level in the area was too high. Unfortunately, the service disruption meant that the system's messages could not be sent, leading to increased levels that precipitated human injuries, writes Notebookcheck. German emergency services had to deploy 40 first responders to the site, with local media reporting that four victims were taken to the hospital for treatment, with one remaining for further observation.

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The tech giant experienced a global outage affecting Outlook and other services from November 12 to 14, which led some Japanese workers to dust off their fax machines to keep their business running. Although this Microsoft outage wasn't as large as the CrowdStrike fiasco in 2024, which led to a massive service disruption to a good number of corporate computer systems and sent shockwaves across the world, this incident has caused injuries and could've even led to something more catastrophic if the issue wasn't caught earlier.

This is one of the issues that institutions must consider when using online services or the Internet of Things to automate systems, especially those that are crucial for safety. Architects of such systems should always have a physical or analog backup that will continue operating even if everything goes offline. More importantly, their people should know that they exist and be familiar with how they work. Alternatively, businesses can host their own servers, build their own automations, and run everything locally, although this would require a bit more involvement in building and programming the entire system. And there could be local infrastructure impacting issues like power cuts, still.

Aside from that, the Microsoft outage also highlights the corporate world's increasing reliance on a few big tech companies. While tech giants like Microsoft, Google, and AWS have the advantage of economies of scale, allowing them to offer their services reliably and more affordably compared to smaller rivals or an in-house deployment, it also means that if they go down, they affect millions of businesses that rely on them and cause economic activity to grind to a halt.