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Concrete pouring

Technical documents

Common Assessment Standard

What is the Common Assessment Standard?

Joint Venture(JV) partners working on HS2 projects will require their suppliers tomprequalify by achieving the Common Assessment Standard (CAS). In addition to providing the JV partners with basic compliance assurance, the CAS offers suppliers a route to prequalification that is uniformly recognised across the HS2 project and increasingly recognised by other commercial and public sector buyers.

CAS assessment is currently available from Achilles, CHAS and Constructionline. These assessors recognise a valid Safety Schemes in Procurement assessment certificate as meeting the basic health and safety requirements of the CAS.

The current CAS question set

Support organisations

The following companies have provided information about their Common Assessment Standard services.


Achilles is the global leader in supply chain risk and performance management services. For nearly 30 years, we’ve been passionate about improving the business performance of our customers and raising standards in the key industries in which we operate.  

We understand that improving productivity, controlling costs and developing customer value are key goals for construction industry buyers and suppliers alike. Since 2007 we have helped drive efficiencies for both Buyers and Suppliers whilst being able to demonstrate how we can influence raising standards within Construction. 

Today, BuildingConfidence is the construction standard providing certification to Safety Schemes in Procurement and the Common Assessment Standard , putting the community at the forefront of standards in the UK. 

Achilles and the Common Assessment Standard


CHAS is the  UK’s Leading Provider of Risk, Compliance and Supply Chain Management Services for Clients and Contractors.vCHAS helps clients (buyers) and contractors (suppliers) ensure compliance across the different areas of risk management, and mitigate risks across the supply chain. We offer accreditation schemes that can help businesses achieve compliance, mitigate supply chain risks and support efficient supply chain management.

With the new Common Assessment Standard, we can review all aspects of your risk management policies in a single annual audit. And as one of the founders of Safety Schemes in Procurement (SSIP), CHAS is committed to setting health and safety benchmarks that drive industries forward and make the world of work a safer place.

Our aim is simple:

  • To standardise and simplify health and safety assessment for contractors
  • To support organisations in efficiently managing their supply chains
  • To deliver a full suite of supply chain management tools.

CHAS and the Common Assessment Standard


Constructionline is the UK’s leading provider of third-party, technology enabled qualification and accreditation services. Constructionline plays a critical role in the Procurement value chain, collecting, assessing and monitoring over 30 million pieces of information, from more than 47,000 suppliers through a PAS 91:2013+A1 2017 aligned question set.

Our aim is to provide efficiency savings and opportunities to Suppliers working with public and private sector Buyers within the construction industry. We achieve this by providing a single source of accreditation, streamlining procurement procedures and improving the supply chain management processes, reducing risk and helping Suppliers work more easily and efficiently with Buyers.

At Constructionline our mission is to help our members simplify procurement tasks, reduce risk, keep pace with legislation and achieve more.

Constructionline and the Common Assessment Standard

Constructionline and EKFB

Rolling Stock

Rolling Stock – Train Technical Specification

Railway Systems

Railway Systems contracts – scope overview

HS2 Ltd policies

HS2 policies (including anti-fraud, quality, environment, sustainability and equality)

Supply Chain communications

Supply Chain communications

HS2 Ltd and the High Speed Rail Group have come together to provide support and guidance to businesses across the HS2 supply chain who want to promote their association with the project through contract wins and job creation. Suppliers wanting to request the guidance should contact their JV comms lead.

To request permission to use the HS2 logo, or the relationship statement ‘supporting the delivery of HS2’, or to feature your work with HS2 in a case study to use on your website or other promotional materials, please consult these guidelines and complete and return this form.