性视界

Power Point - Equations

PowerPoint Accessibility Technical Standard 9: Math & Science (Equations)

The 鈥淲hy鈥� Behind the Standard

Screen readers cannot reliably read equations that are inserted as images or screenshots. Even when alt text is provided, complex equations become difficult to understand because students cannot navigate through individual components.

By using the built鈥慽n Equation Editor, PowerPoint creates MathML鈥攁 machine鈥憆eadable format that allows screen鈥憆eader users to move through a formula step by step and review it at their own pace.

The Goal: Use the native PowerPoint Equation Editor or a dedicated tool such as MathType to create live, navigable math instead of images.

Step 1: Using the Built鈥慖n Equation Editor

Avoid typing math as plain text (for example, using a slash for a fraction). Always use the formal equation tool.

1. Go to the Insert tab.
2. Select Equation (far right). A placeholder will appear labeled 鈥淭ype equation here.鈥�
3. The Equation tab opens in the ribbon, providing structured elements such as fractions, radicals, and integrals.
4. The Rule: Always build equations using the ribbon鈥檚 structure tools so symbols are correctly tagged for assistive technology.

Step 2: Inputting LaTeX or Unicode Math

If you are comfortable with LaTeX, you may use it to speed up equation creation in modern versions of PowerPoint.

1. Open the Equation Editor using Alt + =.
2. In the Equation tab, select LaTeX in the Conversions group.
3. Type your LaTeX code (for example, \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}).
4. Press Enter to convert the code into a fully accessible formatted equation.

Step 3: Handling Complex Science Diagrams

Some scientific visuals鈥攕uch as chemical structures or circuit diagrams鈥� cannot be typed directly and require detailed descriptions.

1. Alt Text: Describe the starting state, the process or reaction, and the outcome.
2. Long Description: If the diagram is critical for exams or labs, provide a detailed explanation in the Slide Notes or as a separate accessible document.
   • Example: A benzene ring consisting of six carbon atoms arranged in a hexagon with alternating double bonds.

Step 4: Avoid 鈥淚nk to Math鈥� for Final Versions

Ink to Math is useful for brainstorming but may misinterpret handwritten symbols, leading to accessibility errors.

1. Use Ink to Math only as a draft tool.
2. Carefully review the converted equation to ensure all symbols, superscripts, and subscripts are correct.
3. If an equation looks incorrect visually, it will likely be read incorrectly by a screen reader.

Step 5: Font Consistency (Cambria Math)

PowerPoint鈥檚 Equation Editor uses Cambria Math by default.

1. The Rule: Do not change equation fonts to match body text fonts such as Arial or Calibri.
2. Why: Cambria Math contains the full set of mathematical glyphs needed for accessible rendering. Changing fonts can break accessibility tagging.

Step 6: Validation and PDF Export

1. Review: Go to Review > Check Accessibility. PowerPoint may not flag equations unless they are images, so manual review is essential.
2. Export to PDF: Use File > Save As, choose PDF, and select 鈥淏est for electronic distribution and accessibility.鈥�
   • Note: Using 鈥淧rint to PDF鈥� strips accessibility tags and converts equations into unreadable images.

Quick Checklist for Math & Science

• [ ] Did I use Insert > Equation instead of an image?
• [ ] Did I build equations using structured elements (fractions, scripts)?
• [ ] For complex diagrams, did I provide a long description?
• [ ] Did I keep equations in Cambria Math?
• [ ] When exporting to PDF, did I choose Best for accessibility?