A Small Practice Guide to Transmission Security: Protecting PHI in Emails and Over Networks (45 CFR 164.312(e))

Executive Summary

For small healthcare practices that rely heavily on email and internet-based systems, protecting patient data during transmission is both a legal and ethical necessity. HIPAA’s Security Rule under § 164.312(e) requires covered entities to implement “technical security measures to guard against unauthorized access to electronic protected health information (ePHI) that is being transmitted over an electronic communications network.” In this guide, we break down what transmission security really means, the risks of noncompliance, and step-by-step actions small practices can take to protect data flowing through email, cloud services, and remote networks without needing an in-house IT department.

Introduction

Sending patient data over the internet is part of everyday life for small practices, whether forwarding lab results to another provider, confirming appointments, or submitting billing data to payers. But every time ePHI moves from one system to another, there’s a risk of interception, alteration, or unauthorized access.

HIPAA’s transmission security standard, located at 45 CFR § 164.312(e), is designed to ensure that ePHI in motion is adequately protected. While the regulation offers flexibility in how to meet the requirement, the responsibility lies squarely on the shoulders of covered entities, including solo providers and small clinics.

This guide is designed to help small practices understand the rule, implement affordable security measures, and avoid costly breaches or audits.

Understanding HIPAA’s Transmission Security Standard

The exact language of § 164.312(e)(1) reads:

“Implement technical security measures to guard against unauthorized access to electronic protected health information that is being transmitted over an electronic communications network.”

This part of the Security Rule applies specifically to data in transit, meaning PHI that is being sent electronically from one location to another, not data stored or accessed locally.

The standard includes two addressable implementation specifications:

• Integrity Controls – Ensure that ePHI is not improperly modified during transmission.
• Encryption – Protect ePHI from unauthorized access during transmission.

“Addressable” doesn’t mean optional, it means that you must implement the measure if reasonable and appropriate, or document why you didn’t and implement an alternative safeguard.

Why Transmission Security Matters for Small Practices

• Limited resources mean fewer internal safeguards
• Frequent email communication increases the chance of accidental exposure
• Use of third-party services like Gmail or Dropbox without proper encryption tools
• Remote access from personal devices or public networks

The consequences of inadequate transmission security can be severe:

• OCR investigations and fines
• Loss of patient trust
• Breaches listed on the HHS "Wall of Shame"
• State-level civil litigation for data exposure

Common ePHI Transmission Scenarios in Small Clinics

Step-by-Step Transmission Security for Small Practices

1. Evaluate Your Current Transmission Channels

Create an inventory of all the ways your practice sends or receives ePHI electronically:

• Email
• Web-based forms
• Text messaging
• Cloud storage (e.g., Google Drive, Dropbox)
• Remote access software
• API connections with third parties

Determine whether each channel is encrypted and access-controlled.

2. Implement Email Encryption

Standard email is not secure. HIPAA requires that emails containing ePHI be encrypted in transit. Affordable options for small practices include:

• Microsoft 365 with built-in message encryption
• Paubox HIPAA-compliant email
• Virtru or Zix email gateways
• G Suite Enterprise with secure transport enforcement

Always use TLS (Transport Layer Security) and configure domain settings to enforce secure connections. If that’s not possible, use patient portals for message delivery.

3. Enable VPN and MFA for Remote Access

If any staff or providers access ePHI from outside the clinic:

• Require use of a VPN (Virtual Private Network) to encrypt internet traffic
• Enforce Multi-Factor Authentication (MFA) to reduce the risk of credential compromise
• Prohibit access over public Wi-Fi unless secure tunnels (VPNs) are used

Free or low-cost VPN tools include:

• ProtonVPN
• OpenVPN
• Twingate

4. Use Integrity Controls to Detect Data Alteration

Ensure that ePHI is not modified in transit using:

• Digital signatures
• Secure file transfer protocols (SFTP)
• Logging and audit trails
• EHR alerts for altered or missing transmission confirmations

Ask vendors whether their platforms include checksum or hash verification tools to track the integrity of files exchanged.

5. Train Staff on Secure Transmission Practices

Your security is only as strong as your staff’s habits. Training should include:

• Never sending ePHI from personal email accounts
• Never texting ePHI without a secure app
• Verifying recipient email addresses before sending
• Knowing what qualifies as PHI
• Documenting patient requests for unencrypted communication

Conduct training at onboarding and annually thereafter.

Case Study: Breach from Unencrypted Referral Email

In 2020, a small specialty clinic experienced a significant HIPAA breach after mistakenly emailing a patient referral to the wrong recipient. The message, which included lab results, prescribed medications, and a summary of clinical findings, was intended for another healthcare provider. However, due to a typographical error in the email address, it was instead sent to an unrelated Gmail user. To make matters worse, the email was unencrypted and contained multiple direct identifiers, including the patient’s full name and date of birth.

Fortunately, the unintended recipient acted responsibly and reported the misdirected message rather than misusing the data. The Office for Civil Rights (OCR) launched an investigation into the incident and discovered that the clinic lacked even basic safeguards for electronic communications. The clinic had no formal encryption policy, had never trained staff on the risks associated with unsecure email, and was unable to provide documentation showing any technical controls for transmitting protected health information (PHI).

As a result, the clinic entered into a resolution agreement and a formal corrective action plan (CAP). The CAP required the adoption of encrypted email systems, mandatory annual HIPAA training for all employees, six months of oversight and documentation review, and publication of the resolution agreement on the HHS website.

This incident underscores the critical need for small practices to implement secure communication protocols and train staff accordingly.

Lesson learned: Even a single email typo can result in a breach if you haven’t implemented encryption or safeguards for transmission.

Checklist: Transmission Security for Small Practices

Regulatory and Trusted References

• 45 CFR § 164.312(e) - Transmission Security
• HHS Emailing and Texting Guidance
• HHS Security Rule Summary
• NIST SP 800-52 – Guidelines for TLS
• OCR Resolution Agreements Archive

Final Takeaways and Recommendations

Transmission security isn’t just for hospitals and big systems, it’s essential for small practices too. Whether you're emailing referrals, allowing remote EHR access, or sending billing data, HIPAA requires you to take steps to prevent unauthorized access or alteration.

If you’re still using unsecured email or public networks without VPN, now is the time to act. Protect your practice by:

• Encrypting all ePHI transmissions
• Training staff and updating policies
• Using tools that log and verify data integrity
• Documenting your decisions and technical safeguards

HIPAA compliance doesn’t have to be expensive, it has to be intentional. Take the right steps now to protect your patients and your practice from unnecessary risk.