No law requires a contractor to hold SSIP: CDM 2015 requires whoever appoints a contractor to take reasonable steps to check its competence, and HSE guidance calls SSIP "one way" to show it, "but not the only way". You still need SSIP, or the Common Assessment Standard, when a client or tender asks for it. PAS 91 has been withdrawn by BSI, and Build UK's Common Assessment Standard is now the industry-agreed prequalification question set.
Is SSIP a legal requirement?
If your clients or the frameworks you bid through ask for an SSIP certificate, you need one to win that work. If nobody asks, the law doesn't make you get one. Those are two different questions, and most of the confusion about SSIP comes from treating them as one.
The legal duty sits with whoever appoints you. Under regulation 8(3) of the Construction (Design and Management) Regulations 2015, a person appointing a designer or contractor "must take reasonable steps to satisfy themselves" that the designer or contractor has the skills, knowledge and experience and, if they are an organisation, the organisational capability to do the work safely. How a client takes those steps is up to them. Many choose to rely on a third-party assessment, and that is where SSIP, PAS 91 and the Common Assessment Standard come in.
What is SSIP?
SSIP (Safety Schemes in Procurement) is an umbrella body for health and safety prequalification schemes. According to SSIP, it was founded in May 2009, with support from HSE, "to streamline prequalification and encourage straightforward mutual recognition between its Member Schemes".
SSIP doesn't assess anyone itself. Its member schemes do, against a shared threshold called the SSIP Core Criteria, which SSIP says are aligned with CDM 2015. The criteria cover, among other things:
- a health and safety policy and the organisation and arrangements to deliver it
- competent health and safety advice, corporate and construction-related
- training and information, and individual qualifications and experience
- monitoring, audit and review, and workforce involvement
- accident reporting and enforcement action, with follow-up investigation
- sub-contracting procedures, risk assessment leading to a safe system of work, and co-operation with others
- welfare provision, plus extra elements for designers, principal designers, principal contractors and fleet operations
SSIP's member list has three categories. Registered Members run SSIP assessments; they include Achilles, Avetta, CHAS, CQMS and SafeContractor. Certification Body Members certify to ISO 45001, and their certificates are recognised by Registered Members. Supporter Members are organisations that recognise SSIP in their own supply chain.
How does deem to satisfy work?
Mutual recognition is the point of SSIP. If you hold a certificate from one member scheme and a client asks for a different one, you can apply to the second scheme for "deem to satisfy". In SSIP's words, the second scheme "checks the existing approval and confirms it meets the same criteria". It may ask for extra information, such as insurance or risk-profile questions, but that is usually much simpler than a full new assessment.
Deem to satisfy is two-way between Registered Members. It is one-way for Certification Body Members: an ISO 45001 certificate can be used with a Registered Member, but not the other way round. It is not free; SSIP publishes the saving each scheme offers against a full assessment, which ranges from 0% to 92%. The accreditation costs guide sets out those figures.
Check the SSIP Portal, not just the PDF. Certificates can be withdrawn or reissued after they're issued, so a certificate on file can be out of date; the SSIP Portal shows a supplier's current status.
What doesn't SSIP tell you?
An SSIP certificate says a company's health and safety management met the core criteria when it was assessed. That is useful, but it is a statement about the company's policies and systems, not about a particular job. On its own it doesn't tell you:
- which operatives the contractor will send, or whether their CSCS, CPCS or IPAF cards are in date on the day
- whether their method statement and risk assessment for your job are any good
- whether their insurance still meets your limits, or whether the company is still trading
- how they actually perform on your site
HSE makes the same point. HSE guidance L153 (paragraph 61) says that as well as pre-qualification checks on organisations, those making appointments "should also check that the designer or contractor has enough experience and a good record in managing the risks involved", ideally at the final stage before appointment. Checking people is covered in our guide to checking CSCS and competency cards.
What happened to PAS 91?
PAS 91 was the British Standards Institution's standard set of construction prequalification questions. The 2013 edition, amended in 2017 (PAS 91:2013+A1:2017), is now listed as withdrawn. CHAS dates the withdrawal to April 2023.
The government followed. Its March 2024 update to the standard selection questionnaire, PPN 03/24, "removed references to PAS91 which has now been withdrawn by the BSI".
You will still see PAS 91 in older tender documents and scheme names; CHAS describes its Advanced level as covering "the former PAS 91" standard. HSE's L153 still refers to PAS 91:2013 as a useful aid to assessing organisational capability (paragraph 60), because L153 itself dates from 2015.
What is the Common Assessment Standard?
The Common Assessment Standard (CAS) is owned by Build UK. It "comprises an industry-agreed question set and corresponding assessment standards for the pre-qualification of suppliers". It was rolled out to the industry in 2021 to cut duplicated prequalification, which was then estimated to cost up to £1bn a year.
CAS goes well beyond health and safety. Version 4 has ten sections: identity, financial, corporate and professional standing, health and safety, environmental, quality, building safety, fairness, inclusion and respect, information security, and information management (Constructionline).
There are two levels: a desktop assessment and a site-based assessment. Build UK lists seven recognised assessment bodies: Achilles, Compliance Chain, Constructionline, CQMS, SCCS, Smas Worksafe and Veriforce CHAS.
| SSIP | PAS 91 | Common Assessment Standard | |
|---|---|---|---|
| Owned by | SSIP Forum and its member schemes | BSI (withdrawn) | Build UK |
| Covers | Health and safety capability (core criteria) | Standard prequalification questions | Ten sections, including H&S, finance, quality, building safety |
| Assessment | By an SSIP member scheme | A question set used by buyers and schemes | Desktop or site-based, by a recognised body |
| Mutual recognition | Deem to satisfy between schemes | Not applicable | One industry-agreed question set for every buyer that uses it |
What do public sector buyers ask for?
Since the Procurement Act 2023, government guidance on conditions of participation says that for works contracts, authorities "can continue to make use of industry pre-qualification questionnaires such as the Common Assessment Standard (CAS)", provided the conditions are proportionate and meet the Act's requirements (Guidance: Conditions of Participation, paragraph 36).
Before the Act, PPN 03/24 had already dropped PAS 91 from the standard questionnaire. Either way, the authority decides what it will accept, so read the tender: some ask for CAS, some for SSIP, and some for your own evidence against their questions.
So do I still need SSIP?
If you're a contractor
Ask your clients. If they require SSIP, CAS or a named scheme, that is a commercial requirement and you will need it for that work. If you hold one SSIP certificate and a client asks for another scheme, ask about deem to satisfy before paying for a full assessment. If nobody requires it, L153 paragraph 65 is clear: "The law does not require any business or individual to use the services of a third party to help them bid for work". You can assess your own capability and give the client the documents yourself.
If you're a client or principal contractor
A certificate can't carry your duty for you. Regulation 8(3) puts the duty on the person making the appointment, and L153 paragraph 60 asks for "sensible and proportionate enquiries" that address the anticipated risks, warning that "excessive or duplicated paperwork should be avoided".
A sensible approach for most clients:
- Decide what each kind of work needs. Low-risk visits may need little more than insurance; high-risk trades need more. Our prequalification checklist sets out a tiered approach.
- Accept SSIP (from any member scheme) or CAS as evidence of organisational capability where it fits, rather than insisting on one scheme.
- Check the certificate's status on the SSIP Portal and record its expiry date.
- Add the checks no scheme does for you: the people, their cards, the job's RAMS, and what happens at your gate.
How Assured Contractors helps
Assured Contractors is not an SSIP scheme and doesn't issue certificates. It is the system a client uses to run its own contractor assurance. Clients set which documents each kind of work needs; contractors store their SSIP or CAS certificate once, with its expiry date, in a profile shared with every client they work for, and get reminders before it lapses. Alongside it sit insurance, Companies House status and every worker's cards. Contractors pay nothing to use Assured Contractors, on any plan; the client pays the subscription. See contractor prequalification, worker competence, or how Assured Contractors compares with the schemes.
Questions
Is SSIP a legal requirement?
No. CDM 2015 requires anyone appointing a contractor to take reasonable steps to check its skills, knowledge, experience and organisational capability. HSE guidance (L153) says SSIP is one way to demonstrate organisational capability, but not the only way, and that the law doesn't require anyone to use a third party to bid for work.
Is PAS 91 still valid?
PAS 91:2013+A1:2017 has been withdrawn by BSI, and the government removed references to it from its standard selection questionnaire in March 2024 (PPN 03/24). Some buyers still use PAS 91-style questions, and some scheme levels refer to the "former PAS 91" standard.
Does the Common Assessment Standard include SSIP?
CAS has its own health and safety section, and assessment bodies such as Veriforce CHAS say their CAS-level certification includes SSIP compliance. Check with your scheme and your client: if a client asks specifically for SSIP, confirm that your CAS certificate will be accepted.
What is deem to satisfy?
If you already hold an SSIP certificate from one member scheme, another member scheme can check that approval and issue its own recognition without a full reassessment. It is usually cheaper than a new assessment, but not always free; SSIP publishes the saving each scheme offers.
How do I check a contractor's SSIP certificate?
Search the SSIP Portal on ssip.org.uk, which HSE describes as a free search facility. SSIP advises buyers to rely on the most recent certificate on the portal rather than a copy supplied by the contractor.
Sources
Checked 11 November 2026. Legislation links go to legislation.gov.uk; guidance links to the publisher's own pages.
- The Construction (Design and Management) Regulations 2015, regulation 8
- HSE L153: Managing health and safety in construction (CDM 2015 guidance)
- SSIP: About
- SSIP Core Criteria
- SSIP Forum members
- SSIP: Deem to satisfy
- GOV.UK: PPN 03/24 Standard Selection Questionnaire
- GOV.UK: Procurement Act 2023 guidance on conditions of participation (April 2026)
- Build UK: Common Assessment Standard
- NBS Publication Index: PAS 91:2013 (+A1:2017), withdrawn
- Constructionline: The Common Assessment Standard explained
- CHAS: PAS 91 vs SSIP vs CAS
- Construction Enquirer: Common prequal system launches to save £1bn in paperwork (March 2021)
This guide is general information, not legal advice. Check the current legislation and guidance for your own site and work.