What is the NASC TG20:13 eGuide?
The purpose of the TG20:13 eGuide is to browse for TG20 compliance sheets: definitions of standard scaffolds that have been designed by structural calculation to BS EN 12811 and do not require additional design.

TG20 compliance sheets specify the design criteria for scaffolding including the height to which it may be safely erected, the maximum dimensions to which it must conform, the leg loads its foundations must support and, where applicable, the ties required to stabilise it.

TG20 compliance sheets can be exported to the Adobe PDF electronic format for printing, saving onto a computer or distribution by email.


Which computers and devices can it be used with?
The TG20:13 eGuide  may be used on any PC desktop computer, laptop computer or tablet running Microsoft Windows 10, 8, or 7, or on an Apple iMac desktop or laptop computer running MacOS X version 10.9 and above.

Note that tablet computers running the Microsoft Windows RT operating system are not supported by the TG20:13 eGuide, but tablets running Windows 10, 8 or 7 are. A version of the eGuide for Android tablets is also available.


How do I install the eGuide onto my computer?
The TG20:13 eGuide must be installed onto a computer before use – it cannot be used directly from a CD.

The TG20:13 eGuide must be downloaded from the TG20 eGuide update page of the NASC web site. Disk copies are no longer issued and previously issued disk versions are now out of date.

You may find you need to download adobe air but please only do this if you experience problems that cannot be fixed by following the Troubleshooting section below.


How do I activate the eGuide with my unique serial number?
The TG20:13 eGuide must be activated before it can be used. Every purchaser of the TG20:13 eGuide is provided with a unique serial number, which entitles you to use the eGuide on one compatible computer or device.

You will be prompted to enter your serial number when you first use the TG20:13 eGuide. You will also need to enter your company name, which should be entered exactly as you wish it to appear on the TG20 compliance sheets printed from the software.

Once the serial number has been entered the eGuide must be activated to ensure that every serial number is only used on one compatible computer or device at a time. The computer or device must be connected to the Internet to activate the TG20:13 eGuide.

When prompted, the ‘Activate now’ option should be selected to register the serial number over the Internet. If the serial number is not already in use, the TG20:13 eGuide will become activated.

If an Internet connection is unavailable, the ‘Activate later’ option can be selected, but the eGuide will run in a limited demonstration mode until it is subsequently activated. While in the demonstration mode it will not be possible to view or print TG20 compliance sheets from the eGuide.


How do I transfer the eGuide to another computer?
The TG20:13 eGuide may be transferred to another computer or device by first deactivating it. This is achieved by selecting the information button (the letter ‘i’) from the menu bar of the Welcome screen.

Then select the ‘click here’ option to deactivate, for which a connection to the Internet is required. The serial number may then be used to activate the TG20:13 eGuide on another computer or device.


How can I email or print a TG20 compliance sheet from the eGuide?
Once a TG20 compliance sheet has been selected using the eGuide, it can be exported to the Adobe PDF electronic format so that it may be printed, saved to the computer or sent by email. This is achieved by selecting the ‘Save as PDF’ option.

The free Adobe Reader software is required to view files in PDF format. It can be downloaded for PC and iMac computers from:



The TG20:13 eGuide fails to activate over the internet.
If the TG20:13 fails to activate over the Internet, and your Internet connection is working, it could be the case that personal firewall software such as Norton or McAfee is blocking the connection.

In most circumstances the firewall software will ask your permission to allow the eGuide to access the Internet: it is important that you allow this in order for the online activation to work.

In some cases, if your firewall software is configured to block Internet connections automatically without asking, you may have to add the TG20:13 eGuide to the list of trusted programs in your firewall software. To do so, please follow these instructions:



Please note that the instructions may differ depending on the version of the firewall program that you have. When you are asked to browse for the eGuide to add it to the safe list (in step 6 of the McAfee instructions) choose: C:\Program Files (x86)\NASC\TG20 eGuide


The TG20:13 eGuide installation fails because the file is damaged.
If you receive an error message during installation that says the TG20:13 eGuide file is damaged, it may be that the anti-virus software on your computer (such as Norton or McAfee) has blocked part of the installation.

To resolve this problem, try temporarily disabling your anti-virus software and re-installing the eGuide. If the problem still exists, it may be that you have insufficient Windows permissions to install the software. To solve this, right-click on setup.exe and choose Run as Administrator.

The NASC is working with anti-virus software publishers to prevent this problem from occuring, but occasional ‘false positives’ do occur. If this problem affects you please contact with the name of your anti-virus software so we can report this problem to the anti-virus software publisher.


The TG20:13 eGuide fails to activate because the serial number is already in use
A TG20:13 serial number can only be used on one computer or compatible mobile device at any time. Please follow the instructions above for moving a serial number from one computer or device to another.
Note: it is important to follow the instructions for deactivating the serial number, which is not the same as uninstalling the eGuide from the computer or device. It is not necessary to uninstall the eGuide software.


Installing the TG20:13 eGuide as an I.T Administrator
If you are installing the TG20:13 eGuide as an Administrator, please log in as the intended user of the software before entering the serial number and activating it.



If you have any problems downloading, installing or activating the TG20 eGuide, technical support is available from CADS, the authors of the TG20 eGuide software.

Telephone support is available from 09:30 – 17:00, Monday to Friday.
+44 (0)1202 603733

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