HTML Entity for Radioactive Sign (☢)

Beginner
6 min read
Updated: Sep 2026
1 example
Unicode U+2622
HTML Entity for radioactive sign (☢) tutorial illustration
Definition

What Is the Radioactive Sign Entity?

Radioactive sign (☢) is the Miscellaneous Symbols character at Unicode U+2622 (RADIOACTIVE SIGN). It marks ionizing radiation hazard for warnings, labels, and science education. There is no named HTML entity; use hex, decimal, UTF-8, or CSS.

Remember
Character     ☢
Unicode       U+2622
Named entity  none
Hex entity    ☢
Decimal       ☢
CSS escape    \2622

All numeric and UTF-8 forms produce the same glyph: ☢. Prefer ☢ for portable markup; paste ☢ in UTF-8 when convenient. Do not confuse it with the biohazard sign (U+2623).

Reference

Quick Reference

One table for every form you will actually use.

FormCodeWhere it goes
Named entitynoneNot defined in HTML5
Hex entity☢HTML markup
Decimal entity☢HTML markup
Direct character☢HTML text (UTF-8 default)
CSS escape\2622Stylesheet content

When to Use Which

SituationUse
Portable HTML without pasting Unicode☢ or ☢
UTF-8 warning / education textType or paste ☢
Generated text via ::before / ::aftercontent: "\2622"
Biological hazard (different symbol)☣ (U+2623)
Accessible safety labelsGlyph + clear wording (e.g. “Radiation hazard”)
See it

Live Preview

Radioactive sign rendered in common contexts.

Glyph ☢
Large glyph ☢
In a label ☢ Radiation hazard
With entities Hex: ☢ | Decimal: ☢ | Named: none
Related ☣ (biohazard) · ⚠ (warning)
Code

Complete HTML Example

One page that shows the radioactive sign with hex, decimal, direct, and CSS forms. Use View Output or open the live editor.

Hex + Decimal + Direct + CSS

Four ways to produce ☢ in a single document (no named entity).

html
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Radioactive Sign (☢) in HTML</title>
  <style>
    #point::after {
      content: "\2622";
    }
  </style>
</head>
<body>
  <p>Using Hex Code: &#x2622;</p>
  <p>Using Decimal: &#9762;</p>
  <p>Using Direct Character: ☢</p>
  <p id="point">Using CSS Entity: </p>
  <p>&#x2622; Radiation hazard</p>
</body>
</html>
Try It Yourself

How It Works

1. Hex: U+2622 → &#x2622; in HTML. Best portable choice (no named entity).

2. Decimal: same code point as 9762 → &#9762;. Same glyph.

3. Direct: paste ☢ in a UTF-8 file with <meta charset="UTF-8">.

4. CSS: use \2622 in content (not an HTML entity). #point::after appends that ☢ after the paragraph text.

5. Named: HTML5 has none — do not invent a name like &radioactive;.

Pitfalls & Tips

Common mistakes when working with this hazard entity.

No name

Do not invent a named entity

There is no &…; name for U+2622. Use &#x2622; or &#9762;.

Not bio

☢ vs ☣

Biohazard is U+2623. Radioactive is U+2622. Do not swap them on safety labels.

A11y

Pair glyph with text

Screen readers may announce ☢ inconsistently. Keep clear wording nearby (e.g. “Radiation hazard”).

Font

Glyph coverage varies

Some fonts omit Miscellaneous Symbols. Provide a fallback font for warning UI.

CSS vs HTML

Do not mix escapes

\2622 belongs in CSS. &#x2622; / &#9762; belong in HTML.

UTF-8

Declare charset

If you paste ☢ directly, serve the page as UTF-8 with <meta charset="UTF-8">.

Compatibility

Browser Support

Radioactive sign (U+2622) and its entity forms (&#x2622;, &#9762;, CSS \\2622) are supported in all mainstream browsers. Glyph availability depends on the font.

✓ Universal support

Radioactive Sign (&#x2622;)

Prefer &#x2622;, or encode with decimal or CSS escape — same glyph everywhere (when the font has it).

100% Browser coverage
Google Chrome Supported
Yes
Microsoft Edge Supported
Yes
Mozilla Firefox Supported
Yes
Apple Safari Supported
Yes
Opera Supported
Yes
Internet Explorer All versions
Yes
U+2622 / entities Full support

Bottom line: There is no named entity. Prefer &#x2622; or &#9762; in HTML, and \\2622 only inside CSS content.

Remember

Key Takeaways

  • Unicode: radioactive sign is U+2622 (decimal 9762), Miscellaneous Symbols.
  • HTML: no named entity — use &#x2622; or &#9762;.
  • CSS: use \2622 inside content for generated text.
  • Meaning: radiation hazard — not ☣ (biohazard).

One line: U+2622 → &#x2622; / &#9762; / CSS \2622 (no named entity).

Frequently Asked Questions

Use &#x2622; (hex), &#9762; (decimal), type ☢ in UTF-8, or the CSS escape \2622 in content. There is no named HTML entity for U+2622.
U+2622 (RADIOACTIVE SIGN). Hex 2622, decimal 9762. It belongs to Miscellaneous Symbols and marks ionizing radiation hazard.
No. HTML5 does not define a named entity for this character. Prefer &#x2622; or &#9762;, or paste ☢ in a UTF-8 document.
Use it for radiation warnings, safety labels, science education, and hazard UI. Prefer &#x2622; for portable markup. Always pair the glyph with clear text for accessibility.
HTML numeric entities (&#9762; or &#x2622;) go in markup. The CSS escape \2622 is used in stylesheets (usually in the content property of ::before/::after). Both render ☢.
☢ (U+2622) is radioactive. ☣ (U+2623) is biohazard (biological risk). Related hazard symbols — different code points. Do not swap them on safety labels.

Did you know?

Radioactive sign (☢) is Unicode U+2622 (decimal 9762) — RADIOACTIVE SIGN in Miscellaneous Symbols. There is no named HTML entity; use &#x2622;, &#9762;, UTF-8 ☢, or CSS \2622. It is not the biohazard sign (☣, U+2623).

Next: Rams Horn

Learn the HTML entity for the rams horn — the next character in this entity sequence.

Rams Horn tutorial →

About the author

Mari Selvan M P
Mari Selvan M P 🔗

Developer, cloud engineer, and technical writer

  • Experience 12 years building web and cloud systems
  • Focus Full Stack Development, AWS, and Developer Education

I write practical tutorials so students and working developers can learn by doing—from databases and APIs to deployment on AWS.

AWS Certified Developer – Associate (Credly)

8 people found this page helpful

HTML Entity | Quotation Mark HTML Entity | Rams Horn