Matthew Dillon

Posted on Jan 20 • Originally published at cleara11y.net on Jan 19

Blockchain-Verified Accessibility: How Hedera Makes Compliance Tamper-Proof

#hedera #blockchain #compliance #verification

The Problem with Traditional Accessibility Reports

When you claim your website is accessible, how do stakeholders verify that claim? Traditional accessibility reports are just PDF files or web pages - easily modified, backdated, or fabricated entirely. This creates several problems:

Legal disputes : When facing an ADA lawsuit, can you prove your accessibility scan results are authentic?
Vendor trust : How do clients know the accessibility report you provided wasn't doctored?
Internal audits : Can you prove to auditors that compliance checks actually happened when claimed?
Procurement requirements : Government contracts often require verified accessibility compliance

A signed PDF helps, but signatures can be forged. What if there was a way to create accessibility records that are mathematically impossible to tamper with?

Enter Hedera: Enterprise-Grade Distributed Ledger

Hedera is a public distributed ledger designed for enterprise use. Unlike traditional blockchains, Hedera uses hashgraph consensus - making it faster, more energy-efficient, and more secure.

Why Hedera for Accessibility Verification?

Feature	Benefit for Accessibility
Immutable records	Once recorded, scan results cannot be altered
Timestamped	Prove exactly when a scan occurred
Publicly verifiable	Anyone can verify a record's authenticity
Carbon negative	Sustainable choice for compliance records
Enterprise governance	Governed by Google, IBM, Boeing, and other major corporations

Hedera processes over 10,000 transactions per second with finality in 3-5 seconds, and each transaction costs a fraction of a cent. This makes it practical for recording every accessibility scan.

How ClearA11y Uses Hedera

When you certify a scan with ClearA11y, here's what happens:

1. Scan Completion

You run an accessibility scan on your website. ClearA11y's scanner (powered by axe-core) checks for WCAG 2.2 violations and generates a detailed report.

2. Report Generation

A PDF report is generated containing:

All issues found with severity levels
Passing checks
AI-generated code fixes
Accessibility score (A through F)

3. Blockchain Certification

When you click "Certify on Hedera", ClearA11y:

1. Computes a SHA-256 hash of your PDF report
2. Creates a certification record with scan metadata
3. Submits the record to Hedera Consensus Service (HCS)
4. Receives a consensus timestamp and transaction ID

4. Immutable Record

The certification record stored on Hedera includes:

{
  "scanId": "scan_abc123",
  "url": "https://example.com",
  "timestamp": "2025-01-19T10:30:00Z",
  "score": "B",
  "wcagLevel": "WCAG 2.2 AA",
  "issues": {
    "critical": 0,
    "serious": 2,
    "moderate": 5,
    "minor": 3
  },
  "pdfHash": "sha256:a1b2c3d4..."
}

This record is now permanent. It cannot be modified, deleted, or backdated - not even by ClearA11y.

Verification: Proving Authenticity

Anyone can verify a ClearA11y report's authenticity using two methods:

Method 1: Verify by Scan ID

Enter the scan ID from your report at cleara11y.net/verify. ClearA11y queries the Hedera network and confirms:

The scan exists on the blockchain
When it was certified
What results were recorded

Method 2: Verify by PDF Upload

Upload your PDF report. ClearA11y:

Computes the SHA-256 hash of your file
Retrieves the original hash from Hedera
Compares them

If the hashes match, the document is authentic and unmodified. If they don't match, the PDF has been tampered with since certification.

Real-World Use Cases

Legal Protection

In an ADA lawsuit, defendants often struggle to prove their remediation efforts. With Hedera-certified scans, you have cryptographic proof that:

Accessibility testing occurred on specific dates
What your compliance status was at each point
No one has modified the historical records

Client Deliverables

Agencies building websites can provide clients with certified accessibility reports. Clients can independently verify the report's authenticity without trusting the agency's word.

Regulatory Compliance

Organizations subject to Section 508, EAA, or other accessibility regulations can maintain a verifiable audit trail of all compliance testing.

Procurement & RFPs

Government contracts requiring accessibility compliance can reference Hedera transaction IDs as proof, verifiable by any third party.

Why Not Just Use a Regular Blockchain?

You might wonder why we chose Hedera over Bitcoin or Ethereum. The reasons are practical:

Speed

Hedera confirms transactions in 3-5 seconds. Ethereum can take minutes; Bitcoin can take hours.

Cost

A Hedera transaction costs approximately $0.0001. An Ethereum transaction can cost $1-50+ during high traffic.

Energy

Hedera is carbon-negative. Bitcoin's proof-of-work consumes enormous energy - not a good look for an accessibility tool promoting inclusive design.

Enterprise Governance

Hedera's governing council includes Google, IBM, Boeing, Deutsche Telekom, and other enterprises. This provides stability and legitimacy for business use.

Getting Started with Certified Scans

Using Hedera certification in ClearA11y is simple:

Run a scan on any URL from your dashboard
Review results and fix critical issues if needed
Click "Certify on Hedera" to create an immutable record
Share the verification link with stakeholders

The certification appears in your scan history with a link to view the record on HashScan (Hedera's block explorer).

The Future of Accessibility Compliance

We believe verified compliance will become the standard. As accessibility lawsuits increase and regulations tighten, organizations need more than promises - they need proof.

Blockchain technology finally makes this possible. Not through hype or speculation, but through practical, affordable, and sustainable record-keeping that anyone can verify.

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