Published 9 September 2026 · Laboratory · Temperature sensors
A lab operating across several sites keeps temperature-controlled storage at each one. Every site runs the same setup: temperature probes reporting to a sensor gateway, which emails an alert when a reading leaves its range.
What is in the storage matters. The record matters as much: the gateway keeps the readings and the alert log, and the lab has to show what was done about each excursion. In a regulated environment, a temperature excursion has to be caught while it is happening and documented afterwards. An excursion discovered the next morning is a compliance problem before it is a spoilage problem.
What an Email Alert Could Not Do
The sensor gateway had always been able to send email. What email could not do was reach the right person at the right site at night, or make sure anyone had heard it. An alert from one site sitting in a shared inbox with alerts from every other site is not a response. It is a queue.
The lab needed three things from the alert path. It had to ring a phone. It had to ring the phone for the site where the excursion was. And it had to be acknowledged by a person, so the response started at the time of the excursion and not at the start of the next shift.
How It Is Set Up
| Sending tool | A temperature sensor gateway that emails on an out-of-range reading, one per site, all sending to the lab's Email2Phone address. |
|---|---|
| Filters | One filter per site, each with a single condition. Example: Subject contains SITE-A, action Call the phone assigned to Site A. Subject contains SITE-B, action Call the phone assigned to Site B. And so on for each location. |
| Acknowledgement | The person who answers presses 8 to save the message, 7 to delete it or 5 to reply. On a phone with voicemail switched off, Email2Phone calls back at 5, 15, 30, 60 and 60 minutes until someone presses a key. |
| Record | The sensor gateway keeps its own log of readings and alerts. Messages also remain in the Email2Phone account's online Message History. |
How the Routing Works
The whole design rests on one subject-line site code per site. The gateway at each location puts its code in the subject of every alert it sends. On the Email2Phone side, one filter per site matches that code and rings the phone assigned to that site.
Every gateway sends to the same Email2Phone address. There is no central dispatcher, no person deciding at 2 a.m. which site an alert belongs to, and no shared inbox. Changing which phone a site's alerts ring means changing one filter, and the gateway is not touched. Adding a site means one more gateway sending to the same address with its own code, and one more filter.
What Happens During an Excursion
A probe reads outside its range. The gateway emails the alert with the site code in the subject. The matching filter rings the phone for that site, and the person who answers presses 1 and hears the message read aloud, subject and body, as the gateway wrote it.
They press 8. That key press marks the alert as acknowledged. On a phone with voicemail switched off, Email2Phone calls back at 5, 15, 30, 60 and 60 minutes until someone presses one. An excursion cannot quietly expire in an inbox.
Email2Phone does not write the compliance record. The gateway logs the reading and the alert; the lab documents what was done about it. Email2Phone's job is the step between those two: making sure the response starts when the excursion happens, not when someone opens the inbox.
Why the Same Setup at Every Site Matters
Because every site uses the same pattern, a gateway with a site code in the subject and a filter to match it. The lab designed that path once and copied it. Staff moving between sites find the same procedure at each: the phone rings, you listen, you press 8. And the phone at each site is a phone number, not an app. Whoever holds the handset that night needs no smartphone and nothing installed. The call rings the number.
What It Does Not Do
Email2Phone does not read the probes, set the thresholds or store the temperature data. The sensor gateway does all of that. Email2Phone's job starts when the gateway sends the email and ends when a person presses a key. For this lab, the missing part was never sensing the excursion. It was getting the right site to hear it and acknowledge it while it was happening.
Get a Phone Call When a Critical Email Arrives
If your sensor gateway can send an email, it can ring a phone. See how email to phone call alerting works for sensor alarms or read about temperature sensor alerts. Or start a free 30-day trial with no credit card and test the site routing with your own gateway.
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