diff --git a/src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java b/src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java
index 500313833..309c1f5eb 100644
--- a/src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java
+++ b/src/main/java/com/adobe/epubcheck/messages/DefaultSeverities.java
@@ -137,6 +137,8 @@ private void initialize()
     severities.put(MessageId.HTM_053, Severity.INFO);
     severities.put(MessageId.HTM_054, Severity.ERROR);
     severities.put(MessageId.HTM_055, Severity.WARNING);
+    severities.put(MessageId.HTM_056, Severity.ERROR);
+    severities.put(MessageId.HTM_057, Severity.ERROR);
 
     // Media
     severities.put(MessageId.MED_001, Severity.ERROR);
diff --git a/src/main/java/com/adobe/epubcheck/messages/MessageId.java b/src/main/java/com/adobe/epubcheck/messages/MessageId.java
index 8ccbcb1e2..6219080ca 100644
--- a/src/main/java/com/adobe/epubcheck/messages/MessageId.java
+++ b/src/main/java/com/adobe/epubcheck/messages/MessageId.java
@@ -131,6 +131,8 @@ public enum MessageId implements Comparable<MessageId>
   HTM_053("HTM_053"),
   HTM_054("HTM_054"),
   HTM_055("HTM_055"),
+  HTM_056("HTM_056"),
+  HTM_057("HTM_057"),
 
   // Messages associated with media (images, audio and video)
   MED_001("MED-001"),
diff --git a/src/main/java/com/adobe/epubcheck/ops/OPSHandler30.java b/src/main/java/com/adobe/epubcheck/ops/OPSHandler30.java
index 2e2968da7..0def5866f 100644
--- a/src/main/java/com/adobe/epubcheck/ops/OPSHandler30.java
+++ b/src/main/java/com/adobe/epubcheck/ops/OPSHandler30.java
@@ -3,6 +3,7 @@
 import java.util.Collections;
 import java.util.EnumSet;
 import java.util.HashSet;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
@@ -11,6 +12,9 @@
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import org.w3c.epubcheck.util.microsyntax.ViewportMeta;
+import org.w3c.epubcheck.util.microsyntax.ViewportMeta.ParseError;
+
 import com.adobe.epubcheck.api.EPUBLocation;
 import com.adobe.epubcheck.api.EPUBProfile;
 import com.adobe.epubcheck.messages.MessageId;
@@ -701,19 +705,55 @@ protected void processMeta()
     if (EpubConstants.HtmlNamespaceUri.equals(e.getNamespace()))
     {
       String name = e.getAttribute("name");
-      if ("viewport".equals(name))
+      if ("viewport".equals(Strings.nullToEmpty(name).trim()))
       {
+        // Mark the viewport as seen
+        // (used when checking the existence of viewport metadata)
         hasViewport = true;
-        // For a fixed-layout document:
-        // check that the vieport declares both height and width
+        // For a fixed-layout documents:
         if (context.opfItem.isPresent() && context.opfItem.get().isFixedLayout())
         {
           String contentAttribute = e.getAttribute("content");
-          if (contentAttribute == null || !contentAttribute.contains("width=")
-              || !contentAttribute.contains("height="))
+
+          // parse viewport metadata
+          List<ViewportMeta.ParseError> syntaxErrors = new LinkedList<>();
+          ViewportMeta viewport = ViewportMeta.parse(contentAttribute,
+              new ViewportMeta.ErrorHandler()
+              {
+                @Override
+                public void error(ParseError error, int position)
+                {
+                  syntaxErrors.add(error);
+                }
+              });
+          if (!syntaxErrors.isEmpty())
+          {
+            // report any syntax error
+            report.message(MessageId.HTM_047, location(), contentAttribute);
+          }
+          else
           {
-            report.message(MessageId.HTM_047, location());
+            // check that viewport metadata has a valid width value
+            if (!viewport.hasProperty("width"))
+            {
+              report.message(MessageId.HTM_056, location(), "width");
+            }
+            else if (!ViewportMeta.isValidWidth(viewport.getValue("width")))
+            {
+              report.message(MessageId.HTM_057, location(), "width");
+            }
+
+            // check that viewport metadata has a valid height value
+            if (!viewport.hasProperty("height"))
+            {
+              report.message(MessageId.HTM_056, location(), "height");
+            }
+            else if (!ViewportMeta.isValidHeight(viewport.getValue("height")))
+            {
+              report.message(MessageId.HTM_057, location(), "height");
+            }
           }
+
         }
       }
     }
diff --git a/src/main/java/com/adobe/epubcheck/util/SourceSet.java b/src/main/java/com/adobe/epubcheck/util/SourceSet.java
index cbf331fcb..f8e6ad058 100644
--- a/src/main/java/com/adobe/epubcheck/util/SourceSet.java
+++ b/src/main/java/com/adobe/epubcheck/util/SourceSet.java
@@ -1,10 +1,14 @@
 package com.adobe.epubcheck.util;
 
+import static org.w3c.epubcheck.util.infra.InfraUtil.isASCIIWhitespace;
+
 import java.nio.CharBuffer;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.regex.Pattern;
 
+import org.w3c.epubcheck.util.infra.InfraUtil;
+
 import com.google.common.base.Function;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
@@ -162,7 +166,7 @@ public SourceSet parse(CharSequence srcset)
         {
         case SPLIT:
           assert (url.length() == 0);
-          if (isASCIIWhitespace(c))
+          if (InfraUtil.isASCIIWhitespace(c))
           {
             // skip whitespace
           }
@@ -271,15 +275,6 @@ else if (c == '(')
       return builder.build();
     }
 
-    /**
-     * if a character is https://infra.spec.whatwg.org/#ascii-whitespace U+0009 TAB,
-     * U+000A LF, U+000C FF, U+000D CR, or U+0020 SPACE.
-     */
-    private static boolean isASCIIWhitespace(char c)
-    {
-      return c == ' ' || c == '\t' || c == '\f' || c == '\n' || c == '\r';
-    }
-
     /**
      * Remove trailing commas and return the count of commas removed
      */
diff --git a/src/main/java/org/w3c/epubcheck/util/infra/InfraUtil.java b/src/main/java/org/w3c/epubcheck/util/infra/InfraUtil.java
new file mode 100644
index 000000000..bf3c9fa7f
--- /dev/null
+++ b/src/main/java/org/w3c/epubcheck/util/infra/InfraUtil.java
@@ -0,0 +1,19 @@
+package org.w3c.epubcheck.util.infra;
+
+public final class InfraUtil
+{
+
+  private InfraUtil()
+  {
+    // static utility class
+  }
+
+  /**
+   * if a character is https://infra.spec.whatwg.org/#ascii-whitespace U+0009
+   * TAB, U+000A LF, U+000C FF, U+000D CR, or U+0020 SPACE.
+   */
+  public static boolean isASCIIWhitespace(char c)
+  {
+    return c == ' ' || c == '\t' || c == '\f' || c == '\n' || c == '\r';
+  }
+}
diff --git a/src/main/java/org/w3c/epubcheck/util/microsyntax/ViewportMeta.java b/src/main/java/org/w3c/epubcheck/util/microsyntax/ViewportMeta.java
new file mode 100644
index 000000000..3120cd460
--- /dev/null
+++ b/src/main/java/org/w3c/epubcheck/util/microsyntax/ViewportMeta.java
@@ -0,0 +1,251 @@
+package org.w3c.epubcheck.util.microsyntax;
+
+import static org.w3c.epubcheck.util.infra.InfraUtil.isASCIIWhitespace;
+
+import java.nio.CharBuffer;
+import java.util.Map;
+import java.util.regex.Pattern;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableMap;
+
+public class ViewportMeta
+{
+  private static Pattern VIEWPORT_HEIGHT_REGEX = Pattern.compile("\\d+|device-height");
+  private static Pattern VIEWPORT_WIDTH_REGEX = Pattern.compile("\\d+|device-width");
+
+  public static ViewportMeta parse(String string, ErrorHandler errorHandler)
+  {
+    return new Parser(errorHandler).parse(string);
+  }
+
+  public static boolean isValidHeight(String height)
+  {
+    Preconditions.checkArgument(height != null);
+    return VIEWPORT_HEIGHT_REGEX.matcher(height).matches();
+  }
+
+  public static boolean isValidWidth(String width)
+  {
+    Preconditions.checkArgument(width != null);
+    return VIEWPORT_WIDTH_REGEX.matcher(width).matches();
+  }
+
+  public static enum ParseError
+  {
+    NULL_OR_EMPTY,
+    NAME_EMPTY,
+    VALUE_EMPTY,
+    LEADING_SEPARATOR,
+    TRAILING_SEPARATOR,
+    ASSIGN_UNEXPECTED
+  }
+
+  /**
+   * An error handler for the `srcset` parser
+   */
+  public interface ErrorHandler
+  {
+    public void error(ParseError error, int position);
+  }
+
+  private final static class Builder
+  {
+    public ImmutableMap.Builder<String, String> properties = ImmutableMap.builder();
+
+    public ViewportMeta build()
+    {
+      return new ViewportMeta(this);
+    }
+
+    public void withProperty(String name, String value)
+    {
+      Preconditions.checkArgument(name != null);
+      Preconditions.checkArgument(value != null);
+      properties.put(name, value);
+    }
+
+  }
+
+  private final static class Parser
+  {
+    private static enum State
+    {
+      NAME,
+      ASSIGN,
+      VALUE,
+      SEPARATOR,
+      SPACE_OR_SEPARATOR
+    }
+
+    private final ErrorHandler errorHandler;
+
+    public Parser(ErrorHandler errorHandler)
+    {
+      this.errorHandler = errorHandler;
+    }
+
+    private void error(ParseError code, int position)
+    {
+      if (errorHandler != null) errorHandler.error(code, position);
+    }
+
+    public ViewportMeta parse(CharSequence string)
+    {
+      Builder builder = new Builder();
+      if (string == null || string.length() == 0)
+      {
+        error(ParseError.NULL_OR_EMPTY, -1);
+        return builder.build();
+      }
+      CharBuffer input = CharBuffer.wrap(string);
+      StringBuilder name = new StringBuilder();
+      StringBuilder value = new StringBuilder();
+      State state = State.NAME;
+      boolean consume = true;
+      char c = ' ';
+      while (!consume || input.hasRemaining())
+      {
+        if (consume)
+        {
+          c = input.get();
+        }
+        else
+        {
+          consume = true;
+        }
+        switch (state)
+        {
+        case NAME:
+          if (isASCIIWhitespace(c) && name.length() == 0)
+          {
+            // skip leading whitespace
+          }
+          else if (c == '=' || isASCIIWhitespace(c))
+          {
+            if (name.length() == 0)
+            {
+              error(ParseError.NAME_EMPTY, input.position());
+              return builder.build();
+            }
+            state = State.ASSIGN;
+            consume = false;
+          }
+          else if (c == ',' || c == ';')
+          {
+            if (name.length() == 0)
+            {
+              error(ParseError.LEADING_SEPARATOR, input.position());
+            }
+            else
+            {
+              error(ParseError.VALUE_EMPTY, input.position());
+            }
+            return builder.build();
+          }
+          else
+          {
+            name.append(c);
+          }
+          break;
+        case ASSIGN:
+          if (isASCIIWhitespace(c))
+          {
+            // skip whitespace
+          }
+          else if (c == '=')
+          {
+            state = State.VALUE;
+          }
+          else
+          {
+            // no '=' was matched (i.e. no value is set)
+            error(ParseError.VALUE_EMPTY, input.position());
+            return builder.build();
+          }
+          break;
+        case VALUE:
+          if (isASCIIWhitespace(c) && value.length() == 0)
+          {
+            // skip whitespace, the value hasn't started
+          }
+          else if (c == ',' || c == ';' || isASCIIWhitespace(c))
+          {
+            if (value.length() == 0)
+            {
+              error(ParseError.VALUE_EMPTY, input.position());
+              return builder.build();
+            }
+            state = State.SPACE_OR_SEPARATOR;
+            consume = false;
+          }
+          else if (c == '=')
+          {
+            error(ParseError.ASSIGN_UNEXPECTED, input.position());
+            return builder.build();
+          }
+          else
+          {
+            value.append(c);
+          }
+          break;
+        case SPACE_OR_SEPARATOR:
+          if (isASCIIWhitespace(c))
+          {
+            // skip whitespace
+          }
+          else
+          {
+            state = State.SEPARATOR;
+            consume = false;
+          }
+        case SEPARATOR:
+          if (c == ',' || c == ';' || isASCIIWhitespace(c))
+          {
+            // skip repeating separators
+          }
+          else
+          {
+            builder.withProperty(name.toString(), value.toString());
+            name = new StringBuilder();
+            value = new StringBuilder();
+            state = State.NAME;
+            consume = false;
+          }
+          break;
+        }
+      }
+      if (value.length() != 0)
+      {
+        builder.withProperty(name.toString(), value.toString());
+      }
+      else if (name.length() != 0)
+      {
+        error(ParseError.VALUE_EMPTY, input.position());
+      }
+      if (state == State.SEPARATOR)
+      {
+        error(ParseError.TRAILING_SEPARATOR, input.position());
+      }
+      return builder.build();
+    }
+  }
+
+  private final Map<String, String> properties;
+
+  private ViewportMeta(Builder builder)
+  {
+    this.properties = builder.properties.build();
+  }
+
+  public boolean hasProperty(String name)
+  {
+    return properties.containsKey(name);
+  }
+
+  public String getValue(String name)
+  {
+    return properties.get(name);
+  }
+
+}
diff --git a/src/main/resources/com/adobe/epubcheck/messages/MessageBundle.properties b/src/main/resources/com/adobe/epubcheck/messages/MessageBundle.properties
index d6a7fb9e6..7f07a57dd 100644
--- a/src/main/resources/com/adobe/epubcheck/messages/MessageBundle.properties
+++ b/src/main/resources/com/adobe/epubcheck/messages/MessageBundle.properties
@@ -111,10 +111,8 @@ HTM_044=Namespace uri "%1$s" was included but not used.
 HTM_044_SUG=Remove unused Namespace URIs.
 HTM_045=Encountered empty href.
 HTM_045_SUG=Empty hrefs are valid self-references.  These should be validated to ensure that this is the desired intent.
-HTM_046=Fixed format item has no viewport defined.
-HTM_046_SUG=A viewport declaration is required for fixed format items.
-HTM_047=Html viewport is missing height and/or width.
-HTM_047_SUG=The viewport declaration must declare both width and height.
+HTM_046=Fixed layout document has no "viewport" meta element.
+HTM_047=Viewport metadata "%1$s" has a syntax error
 HTM_048=SVG Fixed-Layout Documents must have a "viewBox" attribute (on the outermost "svg" element).
 HTM_049=Html element does not have an xmlns set to "http://www.w3.org/1999/xhtml".
 HTM_049_SUG=Add xmlns="http://www.w3.org/1999/xhtml" to the html element.
@@ -124,6 +122,8 @@ HTM_052=The property "region-based" is only allowed on nav elements in Data Navi
 HTM_053=Found an external file link (file://) in file: "%1$s".
 HTM_054=Custom attribute namespace ("%1$s") must not include the string "%2$s" in its domain.
 HTM_055=The "%1$s" element should not be used (discouraged construct)
+HTM_056=Viewport metadata has no "%1$s" dimension (both "width" and "height" properties are required)
+HTM_057=Viewport "%1$s" value must be a positive number or the keyword "device-%1$s" 
 
 #media
 MED_001=Video poster must have core media image type.
diff --git a/src/test/java/org/w3c/epubcheck/util/microsyntax/ViewportSteps.java b/src/test/java/org/w3c/epubcheck/util/microsyntax/ViewportSteps.java
new file mode 100644
index 000000000..625473bfb
--- /dev/null
+++ b/src/test/java/org/w3c/epubcheck/util/microsyntax/ViewportSteps.java
@@ -0,0 +1,75 @@
+package org.w3c.epubcheck.util.microsyntax;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.empty;
+import static org.hamcrest.Matchers.is;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import org.w3c.epubcheck.util.microsyntax.ViewportMeta.ErrorHandler;
+import org.w3c.epubcheck.util.microsyntax.ViewportMeta.ParseError;
+
+import com.google.common.collect.ImmutableList;
+
+import io.cucumber.java.ParameterType;
+import io.cucumber.java.en.Then;
+import io.cucumber.java.en.When;
+
+public class ViewportSteps
+{
+
+  public static final class TestErrorHandler implements ErrorHandler
+  {
+    public final List<ParseError> errors = new LinkedList<>();
+
+    @Override
+    public void error(ParseError error, int position)
+    {
+      errors.add(error);
+    }
+
+    public List<ParseError> errors()
+    {
+      return ImmutableList.copyOf(errors);
+    }
+  };
+
+  private final TestErrorHandler handler;
+
+  public ViewportSteps(TestErrorHandler handler)
+  {
+    this.handler = handler;
+  }
+
+  @ParameterType(".*")
+  public ParseError error(String error)
+  {
+    try
+    {
+      return ParseError.valueOf(error);
+    } catch (Exception e)
+    {
+      throw new IllegalArgumentException("unknown error code '" + error + "'");
+    }
+  }
+
+  @When("parsing viewport {string}")
+  public void parseViewport(String content)
+  {
+    ViewportMeta.parse(content, handler);
+  }
+
+  @Then("no error is returned")
+  public void assertValid()
+  {
+    assertThat("Unexpected errors", handler.errors(), is(empty()));
+  }
+
+  @Then("error {error} is returned")
+  public void assertError(ParseError error)
+  {
+    assertThat(handler.errors(), contains(error));
+  }
+}
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/content_001.xhtml
new file mode 100644
index 000000000..29f2242a7
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal EPUB</title>
+		<meta name="viewport" content="height=705, width=" />
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/nav.xhtml
similarity index 100%
rename from src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/nav.xhtml
rename to src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/nav.xhtml
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/package.opf
new file mode 100644
index 000000000..013c82b7d
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/EPUB/package.opf
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" properties="rendition:layout-pre-paginated rendition:spread-none rendition:page-spread-center"/>
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/META-INF/container.xml
similarity index 100%
rename from src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/META-INF/container.xml
rename to src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/META-INF/container.xml
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/mimetype
similarity index 100%
rename from src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/mimetype
rename to src/test/resources/epub3/08-layout/files/content-fxl-item-xhtml-viewport-invalid-error/mimetype
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/content_001.xhtml
new file mode 100644
index 000000000..a820d396e
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8" />
+		<meta name="viewport" content="width=600,height=" />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/package.opf
similarity index 100%
rename from src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/package.opf
rename to src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/EPUB/package.opf
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-empty-error/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/content_001.xhtml
similarity index 82%
rename from src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/content_001.xhtml
rename to src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/content_001.xhtml
index 855ec7a39..240cdaee4 100644
--- a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-invalid-error/EPUB/content_001.xhtml
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/content_001.xhtml
@@ -2,7 +2,7 @@
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
 	<head>
 		<meta charset="utf-8" />
-		<meta name="viewport" content="width=1200" />
+		<meta name="viewport" content="width=600" />
 		<title>Minimal EPUB</title>
 	</head>
 	<body>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-height-missing-error/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/content_001.xhtml
new file mode 100644
index 000000000..9b4fc899c
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<meta name="viewport" content="width=device-width,height=device-height" />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-keywords-valid/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/content_001.xhtml
new file mode 100644
index 000000000..cc9ac31b9
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/content_001.xhtml
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<meta name="viewport" content="width=600,height=1200" />
+		<meta name="viewport" content="width=600,height=1200" />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-multiple-valid/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/content_001.xhtml
new file mode 100644
index 000000000..ff331a5db
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8" />
+		<meta name="viewport" content="width=600,height=1200,invalid-property" />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-syntax-invalid-error/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/content_001.xhtml
new file mode 100644
index 000000000..b41b24578
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8" />
+		<meta name="viewport" content="width=600px,height=1200px" />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-units-invalid-error/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/content_001.xhtml
new file mode 100644
index 000000000..1713b79db
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/content_001.xhtml
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<meta name="viewport" content="width=600,height=1200" />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-valid/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/content_001.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/content_001.xhtml
new file mode 100644
index 000000000..45c4aface
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/content_001.xhtml
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<meta name="viewport" content="  width	=	600,
+			                               height	=	1200  " />
+		<title>Minimal EPUB</title>
+	</head>
+	<body>
+		<h1>Loomings</h1>
+		<p>Call me Ishmael.</p>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/nav.xhtml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/nav.xhtml
new file mode 100644
index 000000000..240745e63
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/nav.xhtml
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" xml:lang="en" lang="en">
+	<head>
+		<meta charset="utf-8"/>
+		<title>Minimal Nav</title>
+	</head>
+	<body>
+		<nav epub:type="toc">
+			<ol>
+				<li><a href="content_001.xhtml">content 001</a></li>
+			</ol>
+		</nav>
+	</body>
+</html>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/package.opf b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/package.opf
new file mode 100644
index 000000000..d16a30d60
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/EPUB/package.opf
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<package xmlns="http://www.idpf.org/2007/opf" version="3.0" xml:lang="en" unique-identifier="q">
+<metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <dc:title id="title">Minimal EPUB 3.0</dc:title>
+  <dc:language>en</dc:language>
+  <dc:identifier id="q">NOID</dc:identifier>
+  <meta property="dcterms:modified">2017-06-14T00:00:01Z</meta>
+  <meta property="rendition:layout">pre-paginated</meta>
+</metadata>
+<manifest>
+  <item id="content_001"  href="content_001.xhtml" media-type="application/xhtml+xml"/>
+  <item id="nav"  href="nav.xhtml" media-type="application/xhtml+xml" properties="nav"/>
+</manifest>
+<spine>
+  <itemref idref="content_001" />
+</spine>
+</package>
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/META-INF/container.xml b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/META-INF/container.xml
new file mode 100644
index 000000000..318782179
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/META-INF/container.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
+	<rootfiles>
+		<rootfile full-path="EPUB/package.opf" media-type="application/oebps-package+xml"/>
+	</rootfiles>
+</container>
diff --git a/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/mimetype b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/mimetype
new file mode 100644
index 000000000..57ef03f24
--- /dev/null
+++ b/src/test/resources/epub3/08-layout/files/content-fxl-xhtml-viewport-whitespace-valid/mimetype
@@ -0,0 +1 @@
+application/epub+zip
\ No newline at end of file
diff --git a/src/test/resources/epub3/08-layout/layout.feature b/src/test/resources/epub3/08-layout/layout.feature
index b1e564a1f..0beedd609 100644
--- a/src/test/resources/epub3/08-layout/layout.feature
+++ b/src/test/resources/epub3/08-layout/layout.feature
@@ -207,6 +207,26 @@ Feature: EPUB 3 — Layout Rendering Control
 
   #### 8.2.2.6 Content document dimensions
 
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Verify a fixed-layout XHTML document with a valid viewport
+    When checking EPUB 'content-fxl-xhtml-viewport-valid'
+    Then no errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Verify a fixed-layout XHTML document with a valid viewport with whitespace
+    When checking EPUB 'content-fxl-xhtml-viewport-whitespace-valid'
+    Then no errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Verify a fixed-layout XHTML document with a valid viewport using keywords value
+    When checking EPUB 'content-fxl-xhtml-viewport-keywords-valid'
+    Then no errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Verify a fixed-layout XHTML document with multiple viewport meta tags
+    When checking EPUB 'content-fxl-xhtml-viewport-multiple-valid'
+    Then no errors or warnings are reported
+
   @spec @xref:sec-fxl-content-dimensions
   Scenario: Report a fixed-layout XHTML document with no viewport
     When checking EPUB 'content-fxl-xhtml-viewport-missing-error'
@@ -214,8 +234,32 @@ Feature: EPUB 3 — Layout Rendering Control
     And no other errors or warnings are reported
 
   @spec @xref:sec-fxl-content-dimensions
-  Scenario: Report a fixed-layout XHTML document with an invalid viewport
-    When checking EPUB 'content-fxl-xhtml-viewport-invalid-error'
+  Scenario: Report a fixed-layout XHTML document with a syntactically invalid viewport
+    When checking EPUB 'content-fxl-xhtml-viewport-syntax-invalid-error'
+    Then error HTM-047 is reported
+    And no other errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Report a fixed-layout XHTML document with a viewport using units
+    When checking EPUB 'content-fxl-xhtml-viewport-units-invalid-error'
+    Then error HTM-057 is reported 2 times
+    And no other errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Report a fixed-layout XHTML document with a viewport with no height
+    When checking EPUB 'content-fxl-xhtml-viewport-height-missing-error'
+    Then error HTM-056 is reported
+    And no other errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Report a fixed-layout XHTML document with a viewport missing the height value
+    When checking EPUB 'content-fxl-xhtml-viewport-height-empty-error'
+    Then error HTM-047 is reported
+    And no other errors or warnings are reported
+
+  @spec @xref:sec-fxl-content-dimensions
+  Scenario: Report a single fixed-layout XHTML document with an invalid viewport in a reflowable publication
+    When checking EPUB 'content-fxl-item-xhtml-viewport-invalid-error'
     Then error HTM-047 is reported
     And no other errors or warnings are reported
     
diff --git a/src/test/resources/epub3/F-viewport-meta-tag/viewport-syntax.feature b/src/test/resources/epub3/F-viewport-meta-tag/viewport-syntax.feature
new file mode 100644
index 000000000..1eb7c7c65
--- /dev/null
+++ b/src/test/resources/epub3/F-viewport-meta-tag/viewport-syntax.feature
@@ -0,0 +1,49 @@
+Feature: Viewport meta tag syntax
+  
+  Tests the parser for the viewport meta tag syntax as defined
+  in EPUB 3.3:
+    https://www.w3.org/TR/epub-33/#app-viewport-meta-syntax
+    
+  Scenario Outline: parsing valid viewport values
+		When parsing viewport <viewport>
+    Then no error is returned
+    
+    Scenarios:
+      | viewport                     |
+      | "width=1200, height=600"     |
+      | "p1=value"                   |
+      | "  p1  =  value "            |
+      | "	p1	=	value	"              |
+      | "p1  =  value"               |
+      | "p1=value,p2=value"          |
+      | "p1=value;p2=value"          |
+      | "p1=value,,,p2=value"        |
+      | "p1=value;;;p2=value"        |
+      | "p1=value   p2=value"        |
+      | "p1=value, ;p2=value"        |
+      | "p1=value,p2=value,p3=value" |
+    
+  Scenario Outline: parsing invalid viewport values
+		When parsing viewport <viewport>
+    Then error <error> is returned
+    
+    Scenarios:
+      | viewport           | error              |
+      | ""                 | NULL_OR_EMPTY      |
+      | "p1==value"        | ASSIGN_UNEXPECTED  |
+      | "p1=value=value"   | ASSIGN_UNEXPECTED  |
+      | "p1"               | VALUE_EMPTY        |
+      | "p1 value"         | VALUE_EMPTY        |
+      | "p1=value value"   | VALUE_EMPTY        |
+      | "p1,p2=value"      | VALUE_EMPTY        |
+      | "p1=value,p2"      | VALUE_EMPTY        |
+      | "p1="              | VALUE_EMPTY        |
+      | "p1= "             | VALUE_EMPTY        |
+      | "p1=value,p2="     | VALUE_EMPTY        |
+      | "=value"           | NAME_EMPTY         |
+      | "p1=value,=value"  | NAME_EMPTY         |
+      | "p1=value, =value" | NAME_EMPTY         |
+      | ",p1=value"        | LEADING_SEPARATOR  |
+      | ";p1=value"        | LEADING_SEPARATOR  |
+      | "p1=value,"        | TRAILING_SEPARATOR |
+      | "p1=value;"        | TRAILING_SEPARATOR |