SMS Messaging Policy
EAS Station™ documentation
SMS Messaging Policy
Last updated: March 12, 2026
This policy applies to the SMS notification feature of EAS Station™. It describes how text messages are sent, who receives them, and how recipients can opt out.
Program Description
EAS Station™ is a self-hosted Emergency Alert System (EAS) research and monitoring platform. When SMS notifications are enabled by the system administrator, EAS Station™ sends text message alerts to pre-configured recipients whenever an EAS alert is received and broadcast by the system.
Messages are sent via Twilio using a toll-free or long-code phone number provisioned by the system operator. This is not a public subscription service — recipients are added exclusively by the system administrator.
Opt-In Mechanism
EAS Station™ supports two ways a phone number is added to the recipient list:
1. Self-serve double opt-in (recommended). A public page at
/sms-opt-in lets a person enter their own phone number, review the
consent language below, and confirm by entering a one-time code texted to
that number. Only once the code is confirmed is the number added to the
live recipient list. Every attempt — the exact consent text shown, the
submitter's IP address, and the confirmation timestamp — is permanently
recorded and visible to the administrator under Settings → SMS
Notifications → Consent Records. This is the flow a carrier or Twilio
compliance reviewer can be pointed at directly.
Separately from consent, every SMS this system actually sends — alert broadcasts, verification codes, and test messages — is logged under Settings → SMS Notifications → SMS Message Log, searchable by recipient phone number.
Consent checkbox text shown on
/sms-opt-in: "I agree to receive SMS emergency alerts from this EAS Station. Message frequency varies. Message and data rates may apply. Reply STOP to opt out at any time, HELP for help. See the Terms of Use and Privacy Policy."
2. Administrator-added (legacy / non-self-serve cases). The system administrator may still add recipient phone numbers directly in the admin panel under Settings → SMS Notifications → SMS Recipients, for situations where the recipient cannot use the self-serve page themselves. In that case:
- Only individuals who have provided explicit prior written consent may be added.
- Adding a number constitutes the operator's attestation that the individual has consented to receive EAS alert SMS messages from this system.
- Consent must be obtained and documented before any messages are sent.
- Operators submitting a carrier/Twilio campaign for review should prefer the self-serve flow above wherever possible — it produces verifiable evidence this method cannot.
Message Content
Messages contain emergency alert information in the following format:
EAS ALERT: [Event Code]
[Alert Headline]
Areas: [Location Codes]
[Timestamp]
- EAS Station™
Reply STOP to stop msgs
The opt-out reminder (Reply STOP to stop msgs) is appended to every message as required
by CTIA messaging guidelines enforced by Twilio. Messages target under 160 characters for
single-segment delivery where possible.
Message Frequency
Message frequency depends entirely on EAS alert volume from the National Weather Service and other authorized government agencies.
Message frequency varies. During active weather or emergency events, multiple messages may be sent within a short period. During quiet periods, no messages may be sent.
Message & Data Rates
Message and data rates may apply. Standard SMS and data rates charged by the recipient's mobile carrier may apply. EAS Station™ and its operators do not charge any fee for SMS notifications.
How to Opt Out
Reply STOP to any message to stop receiving SMS from this system. You will receive a one-time confirmation and will receive no further messages from this number.
You may also contact the system operator directly and request removal of your number from the admin panel.
| Keyword | Effect |
|---|---|
STOP |
Unsubscribe from all messages |
STOP ALL |
Unsubscribe and block all future messages |
CANCEL |
Unsubscribe from all messages |
END |
Unsubscribe from all messages |
QUIT |
Unsubscribe from all messages |
UNSUBSCRIBE |
Unsubscribe from all messages |
HELP |
Receive help information |
Help
Reply HELP to any message for assistance. You may also contact the system operator through the contact information they have provided.
Supported Carriers
SMS delivery is compatible with all major US wireless carriers including AT&T, T-Mobile, Verizon Wireless, US Cellular, Boost Mobile, Cricket Wireless, and other regional and national carriers.
!!! note Carriers are not liable for delayed or undelivered messages.
Privacy
Phone numbers added to the EAS Station™ SMS recipient list are:
- Stored in the local EAS Station™ database on the operator's infrastructure.
- Transmitted to Twilio, Inc. solely for the purpose of delivering SMS messages.
- Not accessible by the EAS Station™ project maintainers.
See the Privacy Policy for complete data handling details. Twilio's privacy policy is at twilio.com/en-us/legal/privacy.
Operator Compliance Obligations
System operators who enable SMS notifications are responsible for:
- Obtaining and documenting explicit prior written consent from every recipient.
- Disclosing message frequency and "message and data rates may apply" before consent.
- Honoring opt-out (STOP) requests promptly and removing numbers from the admin panel.
- Complying with the Telephone Consumer Protection Act (TCPA) and CTIA guidelines.
- Using SMS only for EAS emergency alert notifications — not marketing or other purposes.
- Submitting toll-free numbers for Twilio verification before production use.
See Twilio Toll-Free Verification for the verification process.
Related Pages
| Resource | Location |
|---|---|
| Notifications setup guide | guides/notifications.md |
| SMS opt-in flow guide | guides/SMS_OPT_IN.md |
| Terms of Use | policies/TERMS_OF_USE.md |
| Privacy Policy | policies/PRIVACY_POLICY.md |
| Live SMS policy page (web UI) | /sms-compliance on your EAS Station™ instance |
| Public opt-in page (web UI) | /sms-opt-in on your EAS Station™ instance |
This document is served from docs/policies/SMS_MESSAGING.md.md in the EAS Station™ installation.