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		<id>https://www.designingbuildings.co.uk/w/index.php?action=history&amp;feed=atom&amp;title=Pipework_defects%2C_ventilation_and_airflow_rates</id>
		<title>Pipework defects, ventilation and airflow rates - Revision history</title>
		<link rel="self" type="application/atom+xml" href="https://www.designingbuildings.co.uk/w/index.php?action=history&amp;feed=atom&amp;title=Pipework_defects%2C_ventilation_and_airflow_rates"/>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;action=history"/>
		<updated>2026-05-18T13:22:40Z</updated>
		<subtitle>Revision history for this page on the wiki</subtitle>
		<generator>MediaWiki 1.17.4</generator>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=188502&amp;oldid=prev</id>
		<title>Editor at 20:56, 4 January 2021</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=188502&amp;oldid=prev"/>
				<updated>2021-01-04T20:56:57Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
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			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 20:56, 4 January 2021&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 49:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 49:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Leaks in buildings.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Leaks in buildings.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;* Plastic-coated steel pipes.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Ultrasonic pipe testing.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Ultrasonic pipe testing.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Editor</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=186826&amp;oldid=prev</id>
		<title>Editor at 12:35, 18 December 2020</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=186826&amp;oldid=prev"/>
				<updated>2020-12-18T12:35:51Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 12:35, 18 December 2020&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 50:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 50:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Leaks in buildings.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Leaks in buildings.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;* Ultrasonic pipe testing.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Valves.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Valves.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Editor</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=186221&amp;oldid=prev</id>
		<title>Designing Buildings at 07:41, 15 December 2020</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=186221&amp;oldid=prev"/>
				<updated>2020-12-15T07:41:25Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
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			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 07:41, 15 December 2020&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 52:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 52:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Valves.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Valves.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;Organisations&lt;/del&gt;]] [[Category:&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;DCN_Organisation&lt;/del&gt;]] [[Category:&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;Standards_/_measurements&lt;/del&gt;]] [[Category:&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;DCN_Standard&lt;/del&gt;]] [[Category:&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;Products_&lt;/del&gt;/&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;_components&lt;/del&gt;]] [[Category:&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;DCN_Product_Knowledge&lt;/del&gt;]]&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;DCN_Definition&lt;/ins&gt;]] [[Category:&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;DCN_Guidance&lt;/ins&gt;]] [[Category:&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;DCN_Product_Knowledge&lt;/ins&gt;]] [[Category:&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;Organisations&lt;/ins&gt;]] [[Category:&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;Standards_&lt;/ins&gt;/&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;_measurements&lt;/ins&gt;]] [[Category:&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;Products_/_components&lt;/ins&gt;]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Designing Buildings</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=156033&amp;oldid=prev</id>
		<title>Designing Buildings at 12:04, 11 March 2020</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=156033&amp;oldid=prev"/>
				<updated>2020-03-11T12:04:14Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 12:04, 11 March 2020&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 34:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 34:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Also, the better the light fitting the more leeway there may be for other items to leak while remaining within the overall total allowance. In practice, leakage through fittings will be very dependent on the ceiling material as well as the care of the fitter but leakage rates do give at least an initial baseline.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Also, the better the light fitting the more leeway there may be for other items to leak while remaining within the overall total allowance. In practice, leakage through fittings will be very dependent on the ceiling material as well as the care of the fitter but leakage rates do give at least an initial baseline.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;--[[User:BSRIA|BSRIA]]&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;--[[User:BSRIA|BSRIA]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;= Find out more =&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Related articles on Designing Buildings Wiki: =&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&amp;#160;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;==&lt;/del&gt;= Related articles on Designing Buildings Wiki: &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;==&lt;/del&gt;=&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Air handling unit.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Air handling unit.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 52:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 48:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Gasket.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Gasket.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;* Leaks in buildings.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Valves.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Valves.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:Organisations&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;]] [[Category:DCN_Organisation&lt;/ins&gt;]] [[Category:Standards_/_measurements&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;]] [[Category:DCN_Standard&lt;/ins&gt;]] [[Category:Products_/_components&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;]] [[Category:DCN_Product_Knowledge&lt;/ins&gt;]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Designing Buildings</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=90530&amp;oldid=prev</id>
		<title>Designing Buildings at 14:58, 6 November 2017</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=90530&amp;oldid=prev"/>
				<updated>2017-11-06T14:58:51Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 14:58, 6 November 2017&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 49:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 49:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Corrosion in heating and cooling systems.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Corrosion in heating and cooling systems.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Domestic ventilation systems performance.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Domestic ventilation systems performance.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;* Flange.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Gasket.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Gasket.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Designing Buildings</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=82085&amp;oldid=prev</id>
		<title>Editor at 12:31, 6 July 2017</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=82085&amp;oldid=prev"/>
				<updated>2017-07-06T12:31:28Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 12:31, 6 July 2017&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 5:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 5:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Could foam insulation be the reason we are experiencing problems with pitting on copper pipework leading to leaks? The copper pipework in question is a chilled water service covered in phenolic foam which is only 4-5 years old. Could the vapour seal on the insulation be damaged leading to condensation forming on the pipe causing pitting and pin-holes?&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Could foam insulation be the reason we are experiencing problems with pitting on copper pipework leading to leaks? The copper pipework in question is a chilled water service covered in phenolic foam which is only 4-5 years old. Could the vapour seal on the insulation be damaged leading to condensation forming on the pipe causing pitting and pin-holes?&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;In order to prove that insulation is the problem you need to establish with certainty that the perforations are from outside to inside and could not have been influenced by other sources of leakage such as weeping joints of previous pinholes. It would also be worth looking at the insulation manufacturer’s guidance to see whether it is the correct grade and has been applied properly. Sometimes there is a protective paper on the inside of the insulation that should not be removed, other manufacturers use an invisible coating or, for steel pipes, may recommend that a protective coating is applied to the pipe prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;In order to prove that insulation is the problem you need to establish with certainty that the perforations are from outside to inside and could not have been influenced by other sources of leakage such as weeping joints of previous pinholes. It would also be worth looking at the insulation manufacturer’s guidance to see whether it is the correct grade and has been applied properly.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&amp;#160;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Sometimes there is a protective paper on the inside of the insulation that should not be removed, other manufacturers use an invisible coating or, for steel pipes, may recommend that a protective coating is applied to the pipe prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Insulation on copper pipework is not a new issue but the European Phenolic Foam Manufacturers Association issued a statement in 2000 after an initial rash of problems.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Insulation on copper pipework is not a new issue but the European Phenolic Foam Manufacturers Association issued a statement in 2000 after an initial rash of problems.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 50:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 52:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;* Valves.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Editor</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=73460&amp;oldid=prev</id>
		<title>Editor at 15:15, 24 March 2017</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=73460&amp;oldid=prev"/>
				<updated>2017-03-24T15:15:53Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 15:15, 24 March 2017&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 13:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 13:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Can stress fractures cause failure with ABS (Acrylonitrile Butadiene Styrene) and PVC pressure pipes?&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Can stress fractures cause failure with ABS (Acrylonitrile Butadiene Styrene) and PVC pressure pipes?&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Stress fractures are the most common defect and are caused by excessive application of adhesive and/or the application of mechanical stress to the joint prior to the adhesive fully curing. This often happens because the pipes and fittings to be connected are slightly misaligned but can be pushed together. A typical stress fracture is a longitudinal crack in the pipe, starting from inside the fitting, or at least near to the fitting. Longitudinal cracks in the middle of a length of pipe are more likely a consequence of impact damage or the pipe being dropped prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Stress fractures are the most common defect and are caused by excessive application of adhesive and/or the application of mechanical stress to the joint prior to the adhesive fully curing. This often happens because the pipes and fittings to be connected are slightly misaligned but can be pushed together.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&amp;#160;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;A typical stress fracture is a longitudinal crack in the pipe, starting from inside the fitting, or at least near to the fitting. Longitudinal cracks in the middle of a length of pipe are more likely a consequence of impact damage or the pipe being dropped prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Cracks may be not readily visible until water starts to appear. Once a crack is suspected then the methods applied by ANS using crack detection fluid can be useful to observe the extent of the crack. More detailed investigation requires the affected section is cut out and sectioned for microscopic examination of both the inside and outside surfaces. Further sections can then be cut to separate the material either side of the crack and examine the fracture surfaces.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Cracks may be not readily visible until water starts to appear. Once a crack is suspected then the methods applied by ANS using crack detection fluid can be useful to observe the extent of the crack. More detailed investigation requires the affected section is cut out and sectioned for microscopic examination of both the inside and outside surfaces. Further sections can then be cut to separate the material either side of the crack and examine the fracture surfaces.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 45:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 47:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Corrosion in heating and cooling systems.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Corrosion in heating and cooling systems.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Domestic ventilation systems performance.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Domestic ventilation systems performance.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;* Gasket.&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Indoor air quality.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;* Refrigerant selection.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;[[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Editor</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=49115&amp;oldid=prev</id>
		<title>Designing Buildings at 14:36, 15 April 2016</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=49115&amp;oldid=prev"/>
				<updated>2016-04-15T14:36:27Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: white; color:black;&quot;&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
			&lt;col class='diff-marker' /&gt;
			&lt;col class='diff-content' /&gt;
		&lt;tr valign='top'&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;← Older revision&lt;/td&gt;
		&lt;td colspan='2' style=&quot;background-color: white; color:black;&quot;&gt;Revision as of 14:36, 15 April 2016&lt;/td&gt;
		&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;The article originally appeared as [https://www.bsria.co.uk/news/article/technical-answers-pipework-defects-ventilation-and-airflow-rates/ Technical answers: Pipework defects, ventilation and airflow rates] published in April 2016&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;. It was &lt;/del&gt;written by Jayne Sunley, Information Manager at BSRIA.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;The article originally appeared as [https://www.bsria.co.uk/news/article/technical-answers-pipework-defects-ventilation-and-airflow-rates/ Technical answers: Pipework defects, ventilation and airflow rates] published in April 2016&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;, &lt;/ins&gt;written by Jayne Sunley, Information Manager at BSRIA.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Foam insulation =&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Foam insulation =&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Could foam insulation be the reason we are experiencing problems with pitting on copper pipework leading to &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;actual &lt;/del&gt;leaks? The copper pipework in question is a chilled water service covered in phenolic foam which is only 4-5 years old. Could the vapour seal on the insulation be damaged leading to condensation forming on the pipe causing pitting and pin-holes?&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Could foam insulation be the reason we are experiencing problems with pitting on copper pipework leading to leaks? The copper pipework in question is a chilled water service covered in phenolic foam which is only 4-5 years old. Could the vapour seal on the insulation be damaged leading to condensation forming on the pipe causing pitting and pin-holes?&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;-----&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;In order to prove that insulation is the problem you need to establish with certainty that the perforations are from outside to inside and could not have been influenced by other sources of leakage such as weeping joints of previous pinholes. It would also be worth looking at the insulation manufacturer’s guidance to see whether it is the correct grade and has been applied properly. Sometimes there is a protective paper on the inside of the insulation that should not be removed, other manufacturers use an invisible coating or&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;, &lt;/ins&gt;for steel pipes&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;, may recommend &lt;/ins&gt;that a protective coating &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;is &lt;/ins&gt;applied to the pipe prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;In order to prove that insulation is the problem you need to establish with &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;all &lt;/del&gt;certainty that the perforations are from outside to inside and could not have been influenced by other sources of leakage such as weeping joints of previous pinholes. It would also be worth looking at the insulation manufacturer’s &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;installation &lt;/del&gt;guidance to see whether it is the correct grade and has been applied properly. Sometimes there is a protective paper on the inside of the insulation that should not be removed, other manufacturers use an invisible coating or &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;may recommend &lt;/del&gt;for steel pipes that a protective coating &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;be &lt;/del&gt;applied to the pipe &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;itself &lt;/del&gt;prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Insulation on copper pipework is not a new issue but the European Phenolic Foam Manufacturers Association issued a statement in 2000 after an initial rash of problems.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Insulation on copper pipework is not a new issue but the European Phenolic Foam Manufacturers Association issued a statement in 2000 after an initial rash of problems.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 12:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 11:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Stress fractures =&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Stress fractures =&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Can stress fractures &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;be the &lt;/del&gt;cause &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;of &lt;/del&gt;failure with ABS and PVC pressure pipes?&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Can stress fractures cause failure with ABS &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;(Acrylonitrile Butadiene Styrene) &lt;/ins&gt;and PVC pressure pipes?&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;-----&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Stress fractures are the most common defect and are caused by excessive application of adhesive and/or the application of mechanical stress to the joint prior to the adhesive fully &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;curing&lt;/ins&gt;. &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;This often &lt;/ins&gt;happens because the pipes and fittings to be connected are slightly misaligned but can be pushed together. &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;A &lt;/ins&gt;typical stress fracture is &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;a &lt;/ins&gt;longitudinal crack in the pipe, starting from inside the fitting, or at least near to the fitting. Longitudinal cracks in the middle of a length of pipe are more likely a consequence of impact damage or the pipe being dropped prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Stress fractures are the most common defect &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;that we see &lt;/del&gt;and are caused by excessive application of adhesive and/or the application of mechanical stress to the joint prior to the adhesive &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;being &lt;/del&gt;fully &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;cured&lt;/del&gt;. &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;Often this &lt;/del&gt;happens because the pipes and fittings to be connected are slightly misaligned but can be pushed together. &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;The &lt;/del&gt;typical stress fracture is longitudinal crack in the pipe, starting from inside the fitting, or at least near to the fitting. Longitudinal cracks in the middle of a length of pipe are more likely &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;to be &lt;/del&gt;a consequence of impact damage or the pipe being dropped prior to installation.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Cracks may be not readily visible until water starts to appear. Once a crack is suspected then the methods applied by ANS using crack detection fluid can be useful to observe the extent of the crack. More detailed investigation requires the affected section &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;to be &lt;/del&gt;cut out &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;from the system &lt;/del&gt;and sectioned for microscopic examination of both inside and outside surfaces. Further sections can then be cut to separate the material either side of the crack and examine the fracture surfaces.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Cracks may be not readily visible until water starts to appear. Once a crack is suspected then the methods applied by ANS using crack detection fluid can be useful to observe the extent of the crack. More detailed investigation requires the affected section &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;is &lt;/ins&gt;cut out and sectioned for microscopic examination of both &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;the &lt;/ins&gt;inside and outside surfaces. Further sections can then be cut to separate the material either side of the crack and examine the fracture surfaces.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Ventilation air speed in ducting =&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Ventilation air speed in ducting =&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 23:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 21:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Are there any recommendations or regulations in the UK about the ventilation air speed in ducting?&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Are there any recommendations or regulations in the UK about the ventilation air speed in ducting?&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;-----&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;There are no regulations in the UK about air velocities in ductwork, however there are recommendations. The BSRIA publication [https://www.bsria.co.uk/information-membership/bookshop/publication/rules-of-thumb-guidelines-for-building-services-5th-edition/ Rules of Thumb] gives recommendations for different applications, for example in offices, 6.0 m/s in main ducts, and 5.5 m/s in branch ducts.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;There are no regulations in the UK about air velocities in ductwork, however there are recommendations. The BSRIA publication [https://www.bsria.co.uk/information-membership/bookshop/publication/rules-of-thumb-guidelines-for-building-services-5th-edition/ Rules of Thumb] gives &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;various &lt;/del&gt;recommendations for different applications, for example in offices, 6.0 m/s in main ducts, and 5.5 m/s in branch ducts.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Airflow rate of LED downlights =&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;= Airflow rate of LED downlights =&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Clients are increasingly asking about the airflow rate of LED downlights but &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;after doing some research as far as I can see, &lt;/del&gt;the airflow rating seems to be of a room/dwelling rather than the particular light fitting in the room. Is this correct?&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;background: #cfc; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;Clients are increasingly asking about the airflow rate of LED downlights but the airflow rating seems to be of a room/dwelling rather than the particular light fitting in the room. Is this correct?&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;minus;&lt;/td&gt;&lt;td style=&quot;background: #ffa; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;&lt;del style=&quot;color: red; font-weight: bold; text-decoration: none;&quot;&gt;-----&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;While airtightness is certainly a requirement of a dwelling or room, to the best of our knowledge there are no specific requirements or limits on individual light fittings. However, each penetration in the ceiling will provide a potential air leakage path and will add to the total leakage. As such, contractors may wish to be sure that if they install a significant number of light fittings they will not exceed the total permitted for the space.&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;div&gt;While airtightness is certainly a requirement of a dwelling or room, to the best of our knowledge there are no specific requirements or limits on individual light fittings. However, each penetration in the ceiling will provide a potential air leakage path and will add to the total leakage. As such, contractors may wish to be sure that if they install a significant number of light fittings they will not exceed the total permitted for the space.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background: #eee; color:black; font-size: smaller;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Designing Buildings</name></author>	</entry>

	<entry>
		<id>https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=49099&amp;oldid=prev</id>
		<title>Editor: Created page with &quot;The article originally appeared as [https://www.bsria.co.uk/news/article/technical-answers-pipework-defects-ventilation-and-airflow-rates/ Technical answers: Pipework defects, ve...&quot;</title>
		<link rel="alternate" type="text/html" href="https://www.designingbuildings.co.uk/w/index.php?title=Pipework_defects,_ventilation_and_airflow_rates&amp;diff=49099&amp;oldid=prev"/>
				<updated>2016-04-15T13:48:17Z</updated>
		
		<summary type="html">&lt;p&gt;Created page with &amp;quot;The article originally appeared as [https://www.bsria.co.uk/news/article/technical-answers-pipework-defects-ventilation-and-airflow-rates/ Technical answers: Pipework defects, ve...&amp;quot;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;The article originally appeared as [https://www.bsria.co.uk/news/article/technical-answers-pipework-defects-ventilation-and-airflow-rates/ Technical answers: Pipework defects, ventilation and airflow rates] published in April 2016. It was written by Jayne Sunley, Information Manager at BSRIA.&lt;br /&gt;
&lt;br /&gt;
= Foam insulation =&lt;br /&gt;
&lt;br /&gt;
Could foam insulation be the reason we are experiencing problems with pitting on copper pipework leading to actual leaks? The copper pipework in question is a chilled water service covered in phenolic foam which is only 4-5 years old. Could the vapour seal on the insulation be damaged leading to condensation forming on the pipe causing pitting and pin-holes?&lt;br /&gt;
&lt;br /&gt;
-----&lt;br /&gt;
In order to prove that insulation is the problem you need to establish with all certainty that the perforations are from outside to inside and could not have been influenced by other sources of leakage such as weeping joints of previous pinholes. It would also be worth looking at the insulation manufacturer’s installation guidance to see whether it is the correct grade and has been applied properly. Sometimes there is a protective paper on the inside of the insulation that should not be removed, other manufacturers use an invisible coating or may recommend for steel pipes that a protective coating be applied to the pipe itself prior to installation.&lt;br /&gt;
&lt;br /&gt;
Insulation on copper pipework is not a new issue but the European Phenolic Foam Manufacturers Association issued a statement in 2000 after an initial rash of problems.&lt;br /&gt;
&lt;br /&gt;
= Stress fractures =&lt;br /&gt;
&lt;br /&gt;
Can stress fractures be the cause of failure with ABS and PVC pressure pipes?&lt;br /&gt;
&lt;br /&gt;
-----&lt;br /&gt;
Stress fractures are the most common defect that we see and are caused by excessive application of adhesive and/or the application of mechanical stress to the joint prior to the adhesive being fully cured. Often this happens because the pipes and fittings to be connected are slightly misaligned but can be pushed together. The typical stress fracture is longitudinal crack in the pipe, starting from inside the fitting, or at least near to the fitting. Longitudinal cracks in the middle of a length of pipe are more likely to be a consequence of impact damage or the pipe being dropped prior to installation.&lt;br /&gt;
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Cracks may be not readily visible until water starts to appear. Once a crack is suspected then the methods applied by ANS using crack detection fluid can be useful to observe the extent of the crack. More detailed investigation requires the affected section to be cut out from the system and sectioned for microscopic examination of both inside and outside surfaces. Further sections can then be cut to separate the material either side of the crack and examine the fracture surfaces.&lt;br /&gt;
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= Ventilation air speed in ducting =&lt;br /&gt;
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Are there any recommendations or regulations in the UK about the ventilation air speed in ducting?&lt;br /&gt;
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There are no regulations in the UK about air velocities in ductwork, however there are recommendations. The BSRIA publication [https://www.bsria.co.uk/information-membership/bookshop/publication/rules-of-thumb-guidelines-for-building-services-5th-edition/ Rules of Thumb] gives various recommendations for different applications, for example in offices, 6.0 m/s in main ducts, and 5.5 m/s in branch ducts.&lt;br /&gt;
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= Airflow rate of LED downlights =&lt;br /&gt;
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Clients are increasingly asking about the airflow rate of LED downlights but after doing some research as far as I can see, the airflow rating seems to be of a room/dwelling rather than the particular light fitting in the room. Is this correct?&lt;br /&gt;
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While airtightness is certainly a requirement of a dwelling or room, to the best of our knowledge there are no specific requirements or limits on individual light fittings. However, each penetration in the ceiling will provide a potential air leakage path and will add to the total leakage. As such, contractors may wish to be sure that if they install a significant number of light fittings they will not exceed the total permitted for the space.&lt;br /&gt;
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Also, the better the light fitting the more leeway there may be for other items to leak while remaining within the overall total allowance. In practice, leakage through fittings will be very dependent on the ceiling material as well as the care of the fitter but leakage rates do give at least an initial baseline.&lt;br /&gt;
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--[[User:BSRIA|BSRIA]]&lt;br /&gt;
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= Find out more =&lt;br /&gt;
&lt;br /&gt;
=== Related articles on Designing Buildings Wiki: ===&lt;br /&gt;
&lt;br /&gt;
* Air handling unit.&lt;br /&gt;
* BSRIA.&lt;br /&gt;
* BSRIA articles on Designing Buildings Wiki.&lt;br /&gt;
* Chilled water.&lt;br /&gt;
* Corrosion in heating and cooling systems.&lt;br /&gt;
* Domestic ventilation systems performance.&lt;br /&gt;
* Indoor air quality.&lt;br /&gt;
* Refrigerant selection.&lt;br /&gt;
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[[Category:Organisations]] [[Category:Standards_/_measurements]] [[Category:Products_/_components]]&lt;/div&gt;</summary>
		<author><name>Editor</name></author>	</entry>

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