diff --git a/.agents/skills/protocol-migration/SKILL.md b/.agents/skills/protocol-migration/SKILL.md
index 7b806de..ea002fe 100644
--- a/.agents/skills/protocol-migration/SKILL.md
+++ b/.agents/skills/protocol-migration/SKILL.md
@@ -45,11 +45,12 @@ You may normalize formatting only when the meaning is unchanged and unambiguous:
 - Standardize chemical formulas with HTML subscripts, for example H2O to H<sub>2</sub>O. Similarly for other chemical formulas (e.g. MgCl2 to MgCl<sub>2</sub>).
 - Do not use Unicode subscript characters such as `₂`.
 - Standardize `RNAseq` or `RNA-Seq` to `RNA-seq`. Same for `ChIP-seq`, `ATAC-seq`, etc.
+- Use numbered lists for procedural actions in sequence. For other non-procedural content, bullets are better. Note-like text such as Note, NB, Optional, Recommended, and Warning should use blockquote style such as `> **Note**`.
 - Normalize bullet formatting and markdown table formatting.
 - Normalize heading structure to match the repository template.
 - For reaction mixes and anything tabular, place them inside a table as in template.
 - Normalize markdown headings, bullets, and tables.
-- "Note" or "NOTE" or "Optional" or "Recommended" or "Warning" are normalized to start with `>` (example `> **Note**`) and are placed immediately after the step they refer to, or at the end of the protocol if they clearly refer to the whole protocol.
+- "Note" or "NOTE" or "NB" or "Optional" or "Recommended" or "Warning" are normalized to start with `>` (example `> **Note**`) and are placed immediately after the step they refer to, or at the end of the protocol if they clearly refer to the whole protocol.
 - Remove empty columns from tables.
 - Synchronize `Contents` with actual headings in the protocol.
 
@@ -82,7 +83,7 @@ You may normalize formatting only when the meaning is unchanged and unambiguous:
 - add `# Migration notes` including:
   - imported protocol metadata from `source-metadata.yml` if present
   - imported protocol metadata from `source-metadata.yml` using only the non-blank lines
-  - template metadata from `template-metadata.yml`
+  - template_version from `template-metadata.yml`
   - ambiguous mappings
   - normalized formatting changes
   - content copied verbatim but not confidently placed
diff --git a/.claude/.claude/skills/protocol-migration/SKILL.md b/.claude/skills/protocol-migration/SKILL.md
similarity index 92%
rename from .claude/.claude/skills/protocol-migration/SKILL.md
rename to .claude/skills/protocol-migration/SKILL.md
index 7b806de..ea002fe 100644
--- a/.claude/.claude/skills/protocol-migration/SKILL.md
+++ b/.claude/skills/protocol-migration/SKILL.md
@@ -45,11 +45,12 @@ You may normalize formatting only when the meaning is unchanged and unambiguous:
 - Standardize chemical formulas with HTML subscripts, for example H2O to H<sub>2</sub>O. Similarly for other chemical formulas (e.g. MgCl2 to MgCl<sub>2</sub>).
 - Do not use Unicode subscript characters such as `₂`.
 - Standardize `RNAseq` or `RNA-Seq` to `RNA-seq`. Same for `ChIP-seq`, `ATAC-seq`, etc.
+- Use numbered lists for procedural actions in sequence. For other non-procedural content, bullets are better. Note-like text such as Note, NB, Optional, Recommended, and Warning should use blockquote style such as `> **Note**`.
 - Normalize bullet formatting and markdown table formatting.
 - Normalize heading structure to match the repository template.
 - For reaction mixes and anything tabular, place them inside a table as in template.
 - Normalize markdown headings, bullets, and tables.
-- "Note" or "NOTE" or "Optional" or "Recommended" or "Warning" are normalized to start with `>` (example `> **Note**`) and are placed immediately after the step they refer to, or at the end of the protocol if they clearly refer to the whole protocol.
+- "Note" or "NOTE" or "NB" or "Optional" or "Recommended" or "Warning" are normalized to start with `>` (example `> **Note**`) and are placed immediately after the step they refer to, or at the end of the protocol if they clearly refer to the whole protocol.
 - Remove empty columns from tables.
 - Synchronize `Contents` with actual headings in the protocol.
 
@@ -82,7 +83,7 @@ You may normalize formatting only when the meaning is unchanged and unambiguous:
 - add `# Migration notes` including:
   - imported protocol metadata from `source-metadata.yml` if present
   - imported protocol metadata from `source-metadata.yml` using only the non-blank lines
-  - template metadata from `template-metadata.yml`
+  - template_version from `template-metadata.yml`
   - ambiguous mappings
   - normalized formatting changes
   - content copied verbatim but not confidently placed
diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
index f312e0e..59337cd 100644
--- a/.github/copilot-instructions.md
+++ b/.github/copilot-instructions.md
@@ -38,11 +38,12 @@ You may normalize formatting only when the meaning is unchanged and unambiguous:
 - Standardize chemical formulas with HTML subscripts, for example H2O to H<sub>2</sub>O. Similarly for other chemical formulas (e.g. MgCl2 to MgCl<sub>2</sub>).
 - Do not use Unicode subscript characters such as `₂`.
 - Standardize `RNAseq` or `RNA-Seq` to `RNA-seq`. Same for `ChIP-seq`, `ATAC-seq`, etc.
+- Use numbered lists for procedural actions in sequence. For other non-procedural content, bullets are better. Note-like text such as Note, NB, Optional, Recommended, and Warning should use blockquote style such as `> **Note**`.
 - Normalize bullet formatting and markdown table formatting.
 - Normalize heading structure to match the repository template.
 - For reaction mixes and anything tabular, place them inside a table as in template.
 - Normalize markdown headings, bullets, and tables.
-- "Note" or "NOTE" or "Optional" or "Recommended" or "Warning" are normalized to start with `>` (example `> **Note**`) and are placed immediately after the step they refer to, or at the end of the protocol if they clearly refer to the whole protocol.
+- "Note" or "NOTE" or "NB" or "Optional" or "Recommended" or "Warning" are normalized to start with `>` (example `> **Note**`) and are placed immediately after the step they refer to, or at the end of the protocol if they clearly refer to the whole protocol.
 - Remove empty columns from tables.
 - Synchronize `Contents` with actual headings in the protocol.
 
@@ -73,7 +74,7 @@ When drafting a migrated protocol:
   - content placed in `## Unplaced content`
   - Imported protocol metadata from `source-metadata.yml` (only the non-blank lines).
   - Imported protocol metadata from `source-metadata.yml` if present.
-  - template metadata from `template-metadata.yml`.
+  - template_version from `template-metadata.yml`.
   - ambiguous mappings.
   - normalized formatting changes.
   - content copied verbatim but not confidently placed.
diff --git a/.github/workflows/validate-protocol.yml b/.github/workflows/validate-protocol.yml
index bd4ea95..e3999e5 100644
--- a/.github/workflows/validate-protocol.yml
+++ b/.github/workflows/validate-protocol.yml
@@ -6,19 +6,23 @@ on:
       - main
     paths:
       - README.md
-      - legacy/source.txt
       - scripts/validate_protocol.py
-      - tests/test_validate_protocol.py
-      - .github/workflows/validate_protocol.yml
+      - scripts/validate_protocol_content.py
+      - scripts/validate_protocol_style.py
+      - tests/test_validate_protocol_content.py
+      - tests/test_validate_protocol_style.py
+      - .github/workflows/validate-protocol.yml
   push:
     branches:
       - main
     paths:
       - README.md
-      - legacy/source.txt
       - scripts/validate_protocol.py
-      - tests/test_validate_protocol.py
-      - .github/workflows/validate_protocol.yml
+      - scripts/validate_protocol_content.py
+      - scripts/validate_protocol_style.py
+      - tests/test_validate_protocol_content.py
+      - tests/test_validate_protocol_style.py
+      - .github/workflows/validate-protocol.yml
   workflow_dispatch:
 
 jobs:
@@ -35,7 +39,7 @@ jobs:
         with:
           python-version: "3.11"
 
-      - name: Check whether validation should run
+      - name: Check whether README validation should run
         id: validation_gate
         run: |
           set -euo pipefail
@@ -56,15 +60,15 @@ jobs:
           echo "should_validate=true" >> "$GITHUB_OUTPUT"
 
       - name: Run validator tests
-        if: steps.validation_gate.outputs.should_validate == 'true'
         run: |
           python -m unittest discover -s tests -p 'test_*.py'
 
-      - name: Run protocol validation
+      - name: Run content validation
         if: steps.validation_gate.outputs.should_validate == 'true'
         run: |
-          if [ -f legacy/source.txt ]; then
-            python scripts/validate_protocol.py README.md legacy/source.txt
-          else
-            python scripts/validate_protocol.py README.md
-          fi
+          python scripts/validate_protocol_content.py README.md
+
+      - name: Run style validation
+        if: steps.validation_gate.outputs.should_validate == 'true'
+        run: |
+          python scripts/validate_protocol_style.py README.md
diff --git a/README.md b/README.md
index a17d4eb..f3fe486 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@
 4. [Step 4](#4-step-4)
 5. [Step 5](#5-step-5)
 6. [Step 6](#6-step-6)
-7. [Buffers](#buffers)
+7. [Materials](#7-materials)
 8. [Migration notes](#migration-notes)
 
 ---
@@ -32,15 +32,15 @@
 
 ## 1.1 Sub-step of Step 1 TODO if Step 1 is complex
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 ## 1.2 Sub-step of Step 1 TODO if Step 1 is complex
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 > **Note:** TODO
 
@@ -48,9 +48,9 @@
 
 # 2. Step 2
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 ## Reagents / mix
 
@@ -66,9 +66,9 @@
 
 # 3. Step 3
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 ## Program / incubation
 
@@ -82,9 +82,9 @@
 
 # 4. Step 4
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 > **Optional:** TODO
 
@@ -92,9 +92,9 @@
 
 # 5. Step 5
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 ## Reaction setup
 
@@ -108,19 +108,22 @@
 
 # 6. Step 6
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 ## Output / QC
 
-- TODO
-- TODO
-- TODO
+1. TODO
+2. TODO
+3. TODO
 
 ---
 
-# 7. Buffers
+# 7. Materials
+
+## 7.1 Buffers
+## 7.2 Reagents
 
 ---
 
@@ -131,4 +134,4 @@
 
 ## Unplaced content
 
-## CHECK items
\ No newline at end of file
+## CHECK items
diff --git a/docs/PROMPT.md b/docs/PROMPT.md
index b991a6d..48b29d6 100644
--- a/docs/PROMPT.md
+++ b/docs/PROMPT.md
@@ -42,9 +42,10 @@ Normalize formatting only when the meaning is unchanged and unambiguous:
 - standardize chemical formulas with HTML subscripts, for example H2O to H<sub>2</sub>O and MgCl2 to MgCl<sub>2</sub>
 - do not use Unicode subscript characters such as `₂`
 - standardize `RNAseq` or `RNA-Seq` to `RNA-seq`, and similarly for `ChIP-seq`, `ATAC-seq`, and related names
+- Use numbered lists for procedural actions in sequence. For other non-procedural content, bullets are better. Note-like text such as Note, NB, Optional, Recommended, and Warning should use blockquote style such as `> **Note**`.
 - normalize bullets, headings, and markdown tables to match the repository template
 - use tables for reaction mixes and other tabular content
-- normalize note-like text to blockquote style, for example `> **Note**`
+- normalize note-like text such as Note, NB, Optional, Recommended, and Warning to blockquote style, for example `> **Note**`
 - place note-like text immediately after the step it refers to, or at the end of the protocol if it clearly refers to the whole protocol
 - remove empty columns from tables
 - synchronize `Contents` with the actual headings in the protocol
@@ -78,7 +79,7 @@ Normalize formatting only when the meaning is unchanged and unambiguous:
 - Include the following in `# Migration notes`:
   - imported protocol metadata from `source-metadata.yml` if present
   - imported protocol metadata from `source-metadata.yml` using only the non-blank lines
-  - template metadata from `template-metadata.yml`
+  - template_version from `template-metadata.yml`
   - ambiguous mappings
   - normalized formatting changes
   - content copied verbatim but not confidently placed
diff --git a/docs/USING_THIS_TEMPLATE.md b/docs/USING_THIS_TEMPLATE.md
index d706253..55bb3e3 100644
--- a/docs/USING_THIS_TEMPLATE.md
+++ b/docs/USING_THIS_TEMPLATE.md
@@ -74,7 +74,7 @@ The main file you must edit for protocol content is `README.md`. Do not rename t
 7. Follow the guidelines in [3. General guidelines for the protocol file (`README.md`)](#3-general-guidelines-for-the-protocol-file-readmemd)
 8. Commit your changes, then push.
 9. Once you are happy with the result, open a pull request from `import-protocol` into `main`.
-10. A validation GitHub Actions workflow will run on that pull request when `README.md` has changed. It checks the required title, status line, status legend, key headings, unresolved placeholders, and placeholder step names. If checks fail, fix them before merging into `main`.
+10. A validation GitHub Actions workflow will run on that pull request when `README.md` has changed. It runs a content check for the required title, status line, status legend, key headings, unresolved placeholders, and placeholder step names, plus a style check for unit formatting. If checks fail, fix them before merging into `main`.
 11. Ask for a reviewer.
 
 > **Note:** Always check accuracy and make sure required sections, such as protocol status and the status legend, are present.
@@ -121,7 +121,7 @@ This route can save time. It helps keep the template structure consistent, norma
 14. Follow the guidelines in [3. General guidelines for the protocol file (`README.md`)](#3-general-guidelines-for-the-protocol-file-readmemd)
 15. Commit your changes, then push.
 16. Once you are happy with the result, open a pull request from `import-protocol` into `main`.
-17. A validation GitHub Actions workflow will run on that pull request when `README.md` has changed. It checks the required title, status line, status legend, key headings, unresolved placeholders, and placeholder step names. If `legacy/source.txt` is present, it also checks that key quantities from the source appear in `README.md`. If checks fail, fix them before merging into `main`.
+17. A validation GitHub Actions workflow will run on that pull request when `README.md` has changed. It runs a content check for the required title, status line, status legend, key headings, unresolved placeholders, and placeholder step names, plus a style check for unit formatting. If checks fail, fix them before merging into `main`.
 18. Ask for a reviewer.
 
 ---
@@ -141,6 +141,7 @@ Mandatory items for validation:
 - a status legend row containing `[OK]`, `[?]`, and `[X]`
 - a short description (`# About`)
 - contents (`## Contents`)
+- a materials section (`# ... Materials`)
 
 Recommended content:
 
diff --git a/docs/template-metadata.yml b/docs/template-metadata.yml
index 8f2e2cb..644e6ce 100644
--- a/docs/template-metadata.yml
+++ b/docs/template-metadata.yml
@@ -6,4 +6,4 @@ template_authors:
   - name: Ira A. Iosub
 template_doi:
 template_version: 1.0.0dev
-template_release_date: 2026-04-10
\ No newline at end of file
+template_release_date: 
\ No newline at end of file
diff --git a/protocol-template.pdf b/protocol-template.pdf
index 17e9476..8d06288 100644
Binary files a/protocol-template.pdf and b/protocol-template.pdf differ
diff --git a/scripts/validate_protocol.py b/scripts/validate_protocol.py
index 43f5554..a9c4444 100644
--- a/scripts/validate_protocol.py
+++ b/scripts/validate_protocol.py
@@ -1,43 +1,15 @@
-"""Validate a protocol README against template requirements and optional source text."""
+"""Backward-compatible entrypoint for protocol README validation."""
 
 from pathlib import Path
-import re
 import sys
 from typing import Dict, List, Optional, Tuple
 
-HEADING_RE = re.compile(r"^(#{1,6})\s+(.+?)\s*$", re.MULTILINE)
-STATUS_LINE_RE = re.compile(
-    r"^### Status:\s+.*`\[(?:OK|\?|X)\]`.*$",
-    re.MULTILINE,
-)
-STATUS_LEGEND_RE = re.compile(
-    r"^\| \*\*\*Status legend\*\*\*:.*`\[OK\]`.*`\[\?\]`.*`\[X\]`.*\|$",
-    re.MULTILINE,
-)
-PLACEHOLDER_STEP_HEADING_RE = re.compile(
-    r"^#{1,6}\s+\d+(?:\.\d+)*(?:\.)?\s+(?:Step|Sub-step)\b.*$",
-    re.MULTILINE,
-)
-PLACEHOLDER_CONTENTS_RE = re.compile(
-    r"^\d+\.\s+\[Step\s+\d+\]\(#.*$",
-    re.MULTILINE,
-)
-
-REQUIRED_HEADINGS = [
-    (1, "About"),
-    (2, "Contents"),
-]
-
-BAD_PLACEHOLDERS = {
-    "TODO": re.compile(r"\bTODO\b"),
-    "TBD": re.compile(r"\bTBD\b"),
-    "XXX": re.compile(r"\bXXX\b"),
-    "CHECK:": re.compile(r"CHECK:"),
-}
-
-DISALLOWED_TEMPLATE_TEXT = [
-    "> Template repository: Click `Use this template` to create a new protocol repo. Template docs are in [docs/USING_THIS_TEMPLATE.md](https://github.com/ulelab/protocol-template/blob/main/docs/USING_THIS_TEMPLATE.md)",
-]
+try:
+    from scripts.validate_protocol_content import validate_readme as validate_content
+    from scripts.validate_protocol_style import validate_readme_style
+except ModuleNotFoundError:
+    from validate_protocol_content import validate_readme as validate_content
+    from validate_protocol_style import validate_readme_style
 
 
 def extract_headings(text: str) -> List[Tuple[int, str]]:
@@ -213,9 +185,7 @@ def main() -> None:
         sys.exit(1)
 
     readme = Path(sys.argv[1]).read_text(encoding="utf-8")
-    source = Path(sys.argv[2]).read_text(encoding="utf-8") if len(sys.argv) == 3 else None
-
-    failures = validate_readme(readme, source)
+    failures = validate_readme(readme)
 
     if failures:
         print("VALIDATION FAILED")
diff --git a/scripts/validate_protocol_content.py b/scripts/validate_protocol_content.py
new file mode 100644
index 0000000..306fba1
--- /dev/null
+++ b/scripts/validate_protocol_content.py
@@ -0,0 +1,161 @@
+"""Validate protocol README content against template requirements."""
+
+from pathlib import Path
+import re
+import sys
+from typing import List, Optional, Tuple
+
+HEADING_RE = re.compile(r"^(#{1,6})\s+(.+?)\s*$", re.MULTILINE)
+STATUS_LINE_RE = re.compile(
+    r"^### Status:\s+.*`\[(?:OK|\?|X)\]`.*$",
+    re.MULTILINE,
+)
+STATUS_LEGEND_RE = re.compile(
+    r"^\| \*\*\*Status legend\*\*\*:.*`\[OK\]`.*`\[\?\]`.*`\[X\]`.*\|$",
+    re.MULTILINE,
+)
+PLACEHOLDER_STEP_HEADING_RE = re.compile(
+    r"^#{1,6}\s+\d+(?:\.\d+)*(?:\.)?\s+(?:Step|Sub-step)\b.*$",
+    re.MULTILINE,
+)
+PLACEHOLDER_CONTENTS_RE = re.compile(
+    r"^\d+\.\s+\[Step\s+\d+\]\(#.*$",
+    re.MULTILINE,
+)
+
+REQUIRED_HEADINGS = [
+    (1, "About"),
+    (2, "Contents"),
+    (1, "Materials"),
+]
+
+BAD_PLACEHOLDERS = {
+    "TODO": re.compile(r"\bTODO\b"),
+    "TBD": re.compile(r"\bTBD\b"),
+    "XXX": re.compile(r"\bXXX\b"),
+    "CHECK:": re.compile(r"CHECK:"),
+}
+
+DISALLOWED_TEMPLATE_TEXT = [
+    "> Template repository: Click `Use this template` to create a new protocol repo. Template docs are in [docs/USING_THIS_TEMPLATE.md](https://github.com/ulelab/protocol-template/blob/main/docs/USING_THIS_TEMPLATE.md)",
+]
+
+
+def extract_headings(text: str) -> List[Tuple[int, str]]:
+    return [(len(level), title.strip()) for level, title in HEADING_RE.findall(text)]
+
+
+def normalize_heading_title(title: str) -> str:
+    return re.sub(r"^\d+(?:\.\d+)*(?:\.)?\s+", "", title).strip()
+
+
+def has_required_heading(
+    headings: List[Tuple[int, str]],
+    required_level: int,
+    required_title: str,
+) -> bool:
+    return any(
+        level == required_level and normalize_heading_title(title) == required_title
+        for level, title in headings
+    )
+
+
+def find_line_number_for_exact_text(text: str, needle: str) -> Optional[int]:
+    for line_number, line in enumerate(text.splitlines(), start=1):
+        if needle in line:
+            return line_number
+    return None
+
+
+def find_line_number_for_regex(
+    text: str,
+    pattern: re.Pattern,
+    target: str,
+) -> Optional[int]:
+    for line_number, line in enumerate(text.splitlines(), start=1):
+        for match in pattern.finditer(line):
+            if match.group(0) == target:
+                return line_number
+    return None
+
+
+def validate_readme(readme: str) -> List[str]:
+    failures: List[str] = []
+    headings = extract_headings(readme)
+    top_level_headings = [title for level, title in headings if level == 1]
+
+    if not headings:
+        failures.append("README does not contain any Markdown headings.")
+    elif not top_level_headings:
+        failures.append("README must contain a top-level protocol title ('# ...').")
+    else:
+        first_title = normalize_heading_title(top_level_headings[0])
+        if first_title == "About":
+            failures.append("Missing top-level protocol title before '# About'.")
+
+    for level, title in REQUIRED_HEADINGS:
+        if not has_required_heading(headings, level, title):
+            failures.append(f"Missing heading: {'#' * level} {title}")
+
+    if not STATUS_LINE_RE.search(readme):
+        failures.append("Missing or malformed status line: expected '### Status: ...'.")
+
+    if not STATUS_LEGEND_RE.search(readme):
+        failures.append(
+            "Missing or malformed status legend row with `[OK]`, `[?]`, and `[X]`."
+        )
+
+    for token, pattern in BAD_PLACEHOLDERS.items():
+        if pattern.search(readme):
+            failures.append(f"Found unresolved placeholder: {token}")
+
+    for text in DISALLOWED_TEMPLATE_TEXT:
+        if text in readme:
+            line_number = find_line_number_for_exact_text(readme, text)
+            if line_number is None:
+                failures.append(f"Found template-only text that must be removed: {text}")
+            else:
+                failures.append(
+                    f"Found template-only text that must be removed: {text} (README line {line_number})"
+                )
+
+    for match in PLACEHOLDER_STEP_HEADING_RE.findall(readme):
+        line_number = find_line_number_for_regex(readme, PLACEHOLDER_STEP_HEADING_RE, match)
+        if line_number is None:
+            failures.append(f"Found placeholder step heading: {match}")
+        else:
+            failures.append(
+                f"Found placeholder step heading: {match} (README line {line_number})"
+            )
+
+    for match in PLACEHOLDER_CONTENTS_RE.findall(readme):
+        line_number = find_line_number_for_regex(readme, PLACEHOLDER_CONTENTS_RE, match)
+        if line_number is None:
+            failures.append(f"Found placeholder contents entry: {match}")
+        else:
+            failures.append(
+                f"Found placeholder contents entry: {match} (README line {line_number})"
+            )
+
+    return list(dict.fromkeys(failures))
+
+
+def main() -> None:
+    if len(sys.argv) != 2:
+        print("Usage: python validate_protocol_content.py README.md")
+        sys.exit(1)
+
+    readme = Path(sys.argv[1]).read_text(encoding="utf-8")
+    failures = validate_readme(readme)
+
+    if failures:
+        print("VALIDATION FAILED")
+        for failure in failures:
+            print(f"- {failure}")
+        sys.exit(1)
+
+    print("Content validation passed.")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/scripts/validate_protocol_style.py b/scripts/validate_protocol_style.py
new file mode 100644
index 0000000..fb8e140
--- /dev/null
+++ b/scripts/validate_protocol_style.py
@@ -0,0 +1,171 @@
+"""Validate protocol README unit and notation style."""
+
+from pathlib import Path
+import re
+import sys
+from typing import List
+
+NUMBER_RE = r"\d+(?:\.\d+)?"
+TEMPERATURE_RE = re.compile(
+    rf"\b(?P<value>{NUMBER_RE})(?P<space1>\s*)(?P<degree>°?)(?P<space2>\s*)(?P<unit>[Cc])\b"
+)
+PH_RE = re.compile(r"\b(?P<label>[Pp][Hh])(?P<space>\s*)(?P<value>\d+(?:\.\d+)?)\b")
+MICRO_UNIT_RE = re.compile(
+    rf"\b(?P<value>{NUMBER_RE})(?P<space>\s*)(?P<unit>uL|ul|UL|uM|UM|ug|μL|μM|μg)\b"
+)
+UNIT_RE = re.compile(
+    rf"\b(?P<value>{NUMBER_RE})(?P<space>\s*)(?P<unit>µL|mL|ml|ML|L|l|µg|mg|g|kg|ng|mM|µM|nM|M|μL|μM|μg)\b"
+)
+TIME_RE = re.compile(
+    rf"\b(?P<value>{NUMBER_RE})(?P<space>\s*)(?P<unit>seconds?|second|minutes?|minute|hours?|hour|secs?|sec|mins?|min|hrs?|hr|s|h)\b",
+    re.IGNORECASE,
+)
+CHEMICAL_FORMULA_RE = re.compile(
+    r"\b(?P<formula>(?:[A-Z][a-z]?\d*){2,})\b"
+)
+UNICODE_SUBSCRIPT_RE = re.compile(r"\b(?P<formula>[A-Za-z₀₁₂₃₄₅₆₇₈₉]+)\b")
+
+PREFERRED_MICRO_UNITS = {
+    "ul": "µL",
+    "um": "µM",
+    "ug": "µg",
+    "μl": "µL",
+    "μm": "µM",
+    "μg": "µg",
+}
+PREFERRED_UNITS = {
+    "µl": "µL",
+    "μl": "µL",
+    "ml": "mL",
+    "l": "L",
+    "µg": "µg",
+    "μg": "µg",
+    "mg": "mg",
+    "g": "g",
+    "kg": "kg",
+    "ng": "ng",
+    "mm": "mM",
+    "µm": "µM",
+    "μm": "µM",
+    "m": "M",
+}
+TIME_UNIT_BASE = {
+    "s": "second",
+    "sec": "second",
+    "secs": "second",
+    "second": "second",
+    "seconds": "second",
+    "min": "minute",
+    "mins": "minute",
+    "minute": "minute",
+    "minutes": "minute",
+    "h": "hour",
+    "hr": "hour",
+    "hrs": "hour",
+    "hour": "hour",
+    "hours": "hour",
+}
+UNICODE_SUBSCRIPT_MAP = str.maketrans("₀₁₂₃₄₅₆₇₈₉", "0123456789")
+
+
+def preferred_time_token(value: str, unit: str) -> str:
+    base = TIME_UNIT_BASE[unit.lower()]
+    plural = "" if value == "1" else "s"
+    return f"{value} {base}{plural}"
+
+
+def html_subscript_formula(formula: str) -> str:
+    return re.sub(r"(\d+)", r"<sub>\1</sub>", formula)
+
+
+def format_unit_failure(line_number: int, found: str, preferred: str) -> str:
+    if "μ" in found:
+        return (
+            f"Line {line_number}: unit uses Greek mu `μ`; use the micro sign `µ` "
+            f"in `{preferred}` instead of `{found}`."
+        )
+
+    return f"Line {line_number}: unit should use `{preferred}` style, found `{found}`."
+
+
+def validate_readme_style(readme: str) -> List[str]:
+    failures: List[str] = []
+
+    for line_number, line in enumerate(readme.splitlines(), start=1):
+        for match in TEMPERATURE_RE.finditer(line):
+            preferred = f"{match.group('value')} °C"
+            if match.group(0) != preferred:
+                failures.append(
+                    f"Line {line_number}: temperature should use `{preferred}` style, found `{match.group(0)}`."
+                )
+
+        for match in MICRO_UNIT_RE.finditer(line):
+            preferred_unit = PREFERRED_MICRO_UNITS[match.group("unit").lower()]
+            preferred = f"{match.group('value')} {preferred_unit}"
+            if match.group(0) != preferred:
+                failures.append(format_unit_failure(line_number, match.group(0), preferred))
+
+        for match in UNIT_RE.finditer(line):
+            preferred_unit = PREFERRED_UNITS[match.group("unit").lower()]
+            preferred = f"{match.group('value')} {preferred_unit}"
+            if match.group(0) != preferred:
+                failures.append(format_unit_failure(line_number, match.group(0), preferred))
+
+        for match in TIME_RE.finditer(line):
+            preferred = preferred_time_token(match.group("value"), match.group("unit"))
+            if match.group(0) != preferred:
+                failures.append(
+                    f"Line {line_number}: time should use full-word units like `{preferred}`, found `{match.group(0)}`."
+                )
+
+        for match in PH_RE.finditer(line):
+            preferred = f"pH {match.group('value')}"
+            if match.group(0) != preferred:
+                failures.append(
+                    f"Line {line_number}: pH should use `{preferred}` style, found `{match.group(0)}`."
+                )
+
+        for match in CHEMICAL_FORMULA_RE.finditer(line):
+            formula = match.group("formula")
+            if "<sub>" in formula or not any(char.isdigit() for char in formula):
+                continue
+
+            preferred = html_subscript_formula(formula)
+            if formula != preferred:
+                failures.append(
+                    f"Line {line_number}: chemical formula should use `{preferred}` style, found `{formula}`."
+                )
+
+        for match in UNICODE_SUBSCRIPT_RE.finditer(line):
+            formula = match.group("formula")
+            if not any(char in "₀₁₂₃₄₅₆₇₈₉" for char in formula):
+                continue
+
+            normalized = formula.translate(UNICODE_SUBSCRIPT_MAP)
+            preferred = html_subscript_formula(normalized)
+            failures.append(
+                f"Line {line_number}: chemical formula should use `{preferred}` style, found `{formula}`."
+            )
+
+    return list(dict.fromkeys(failures))
+
+
+def main() -> None:
+    if len(sys.argv) != 2:
+        print("Usage: python validate_protocol_style.py README.md")
+        sys.exit(1)
+
+    readme = Path(sys.argv[1]).read_text(encoding="utf-8")
+    failures = validate_readme_style(readme)
+
+    if failures:
+        print("VALIDATION FAILED")
+        for failure in failures:
+            print(f"- {failure}")
+        sys.exit(1)
+
+    print("Style validation passed.")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tests/test_validate_protocol.py b/tests/test_validate_protocol_content.py
similarity index 54%
rename from tests/test_validate_protocol.py
rename to tests/test_validate_protocol_content.py
index 948b578..29ad014 100644
--- a/tests/test_validate_protocol.py
+++ b/tests/test_validate_protocol_content.py
@@ -1,8 +1,8 @@
-"""Tests for the protocol README validator."""
+"""Tests for the protocol README content validator."""
 
 import unittest
 
-from scripts.validate_protocol import validate_readme
+from scripts.validate_protocol_content import validate_readme
 
 
 VALID_README = """# RNA extraction
@@ -18,6 +18,7 @@
 ## Contents
 1. [Lysis](#1-lysis)
 2. [Cleanup](#2-cleanup)
+3. [Materials](#3-materials)
 
 # 1. Lysis
 
@@ -26,12 +27,17 @@
 # 2. Cleanup
 
 Wash with 70% ethanol and elute.
+
+# 3. Materials
+
+- Lysis buffer
+- Ethanol
 """
 
 TEMPLATE_NOTE = "> Template repository: Click `Use this template` to create a new protocol repo. Template docs are in [docs/USING_THIS_TEMPLATE.md](https://github.com/ulelab/protocol-template/blob/main/docs/USING_THIS_TEMPLATE.md)\n\n"
 
 
-class ValidateReadmeTests(unittest.TestCase):
+class ValidateReadmeContentTests(unittest.TestCase):
     def test_valid_readme_passes(self) -> None:
         self.assertEqual(validate_readme(VALID_README), [])
 
@@ -42,6 +48,12 @@ def test_missing_protocol_title_before_about_fails(self) -> None:
             validate_readme(readme),
         )
 
+    def test_materials_heading_is_required(self) -> None:
+        readme = VALID_README.replace("3. [Materials](#3-materials)\n", "", 1)
+        readme = readme.replace("\n# 3. Materials\n\n- Lysis buffer\n- Ethanol\n", "", 1)
+
+        self.assertIn("Missing heading: # Materials", validate_readme(readme))
+
     def test_placeholder_step_headings_and_contents_are_reported(self) -> None:
         readme = VALID_README.replace("[Lysis](#1-lysis)", "[Step 1](#1-step-1)", 1)
         readme = readme.replace("# 1. Lysis", "# 1. Step 1", 1)
@@ -49,7 +61,7 @@ def test_placeholder_step_headings_and_contents_are_reported(self) -> None:
         failures = validate_readme(readme)
 
         self.assertIn(
-            "Found placeholder step heading: # 1. Step 1 (README line 15)",
+            "Found placeholder step heading: # 1. Step 1 (README line 16)",
             failures,
         )
         self.assertIn(
@@ -57,40 +69,6 @@ def test_placeholder_step_headings_and_contents_are_reported(self) -> None:
             failures,
         )
 
-    def test_source_token_matching_normalizes_micro_symbol(self) -> None:
-        source = "Use 10 µL reagent for 5 min at 20 C and finish in 70% ethanol."
-        self.assertEqual(validate_readme(VALID_README, source), [])
-
-    def test_source_token_matching_normalizes_greek_mu_symbol(self) -> None:
-        source = "Use 10 μL reagent for 5 min at 20 C and finish in 70% ethanol."
-        self.assertEqual(validate_readme(VALID_README, source), [])
-
-    def test_source_token_matching_allows_spacing_and_unit_normalization(self) -> None:
-        source = "Use 1uL primer, 20ul water, incubate 10min at 65C, then hold 30min at 42  C."
-        readme = VALID_README.replace(
-            "Add 10 uL lysis buffer and incubate for 5 min at 20 C.",
-            "Add 1 µL primer and 20 µL water, incubate for 10 minutes at 65 °C, then hold for 30 minutes at 42 °C.",
-            1,
-        )
-        self.assertEqual(validate_readme(readme, source), [])
-
-    def test_source_token_matching_works_for_table_values(self) -> None:
-        source = "Prepare mix with 0.25 μL enzyme and 0.5μL buffer."
-        readme = VALID_README.replace(
-            "Add 10 uL lysis buffer and incubate for 5 min at 20 C.",
-            "| Component | Volume |\n|---|---|\n| Enzyme | 0.25 µL |\n| Buffer | 0.5 µL |",
-            1,
-        )
-        self.assertEqual(validate_readme(readme, source), [])
-
-    def test_missing_source_tokens_are_grouped_with_source_lines(self) -> None:
-        source = "Add 0.5 μL enzyme.\nRepeat with 0.5µL enzyme."
-        failures = validate_readme(VALID_README, source)
-        self.assertIn(
-            "Source token missing from README: 0.5 μL (source line 1; all source lines: 1, 2)",
-            failures,
-        )
-
     def test_missing_status_line_is_reported(self) -> None:
         readme = VALID_README.replace(
             "### Status: 🟢 `[OK]` | validated and ready to use\n",
diff --git a/tests/test_validate_protocol_style.py b/tests/test_validate_protocol_style.py
new file mode 100644
index 0000000..38035af
--- /dev/null
+++ b/tests/test_validate_protocol_style.py
@@ -0,0 +1,129 @@
+"""Tests for the protocol README style validator."""
+
+import unittest
+
+from scripts.validate_protocol_style import validate_readme_style
+
+
+VALID_README = """# RNA extraction
+
+### Status: 🟢 `[OK]` | validated and ready to use
+| ***Status legend***: | 🟢 `[OK]` working | 🟡 `[?]` unconfirmed / partial | 🔴 `[X]` broken |
+|---|---|---|---|
+
+# About
+
+Extract total RNA from cultured cells.
+
+## Contents
+1. [Lysis](#1-lysis)
+2. [Cleanup](#2-cleanup)
+3. [Materials](#3-materials)
+
+# 1. Lysis
+
+Add 10 µL lysis buffer and incubate for 5 minutes at 20 °C.
+Adjust to pH 7.4 with 1 mM Tris-HCl.
+Prepare with H<sub>2</sub>O and MgCl<sub>2</sub>.
+
+# 2. Cleanup
+
+Wash with ethanol and elute.
+
+# 3. Materials
+
+- 10 µL pipette
+- 1 mM Tris-HCl
+"""
+
+
+class ValidateReadmeStyleTests(unittest.TestCase):
+    def test_valid_readme_passes(self) -> None:
+        self.assertEqual(validate_readme_style(VALID_README), [])
+
+    def test_volume_and_time_formatting_are_reported(self) -> None:
+        readme = VALID_README.replace(
+            "Add 10 µL lysis buffer and incubate for 5 minutes at 20 °C.",
+            "Add 10uL lysis buffer and incubate for 5 min at 20 °C.",
+            1,
+        )
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any("unit should use `10 µL` style" in failure for failure in failures)
+        )
+        self.assertTrue(
+            any(
+                "time should use full-word units like `5 minutes`" in failure
+                for failure in failures
+            )
+        )
+
+    def test_temperature_formatting_is_reported(self) -> None:
+        readme = VALID_README.replace("20 °C", "20C", 1)
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any("temperature should use `20 °C` style" in failure for failure in failures)
+        )
+
+    def test_micro_sign_and_unit_case_are_reported(self) -> None:
+        readme = VALID_README.replace("1 mM Tris-HCl", "1uM Tris-HCl", 1)
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any("unit should use `1 µM` style" in failure for failure in failures)
+        )
+
+    def test_greek_mu_is_reported_and_normalized_to_micro_sign(self) -> None:
+        readme = VALID_README.replace("10 µL lysis buffer", "10 μL lysis buffer", 1)
+        readme = readme.replace("10 µL pipette", "10 μL pipette", 1)
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any(
+                "unit uses Greek mu `μ`; use the micro sign `µ`" in failure
+                for failure in failures
+            )
+        )
+
+    def test_ph_spacing_and_case_are_reported(self) -> None:
+        readme = VALID_README.replace("pH 7.4", "PH7.4", 1)
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any("pH should use `pH 7.4` style" in failure for failure in failures)
+        )
+
+    def test_plain_chemical_formula_uses_html_subscripts(self) -> None:
+        readme = VALID_README.replace("H<sub>2</sub>O", "H2O", 1)
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any(
+                "chemical formula should use `H<sub>2</sub>O` style" in failure
+                for failure in failures
+            )
+        )
+
+    def test_unicode_subscript_formula_is_reported(self) -> None:
+        readme = VALID_README.replace("MgCl<sub>2</sub>", "MgCl₂", 1)
+
+        failures = validate_readme_style(readme)
+
+        self.assertTrue(
+            any(
+                "chemical formula should use `MgCl<sub>2</sub>` style" in failure
+                for failure in failures
+            )
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()