ISO Certifications and SOA Qualification: Roles and Differences
In the construction and public works sector, reference is often made to ISO certifications, SOA qualification, and other qualification or rating systems.
ISO and SOA are fundamentally different instruments, with distinct purposes, scopes of application, and legal effects. Understanding these differences is essential in order to navigate the regulatory framework correctly and adopt the qualifications required for a company’s activities.
SOA Qualification
Mandatory qualification for public works contracts above €150,000
ISO Certifications
Voluntary standards certifying corporate systems and processes
Other Standards and Protocols
Voluntary schemes that complement ISO and SOA, without replacing them
ISO and SOA: Key Differences
ISO and SOA respond to entirely different regulatory logics and are not interchangeable.
- ISO certifications attest how a company operates
- SOA qualification certifies whether a company is legally qualified to execute public works
ISO certifications never replace SOA qualification, but they may:
- Be required in tender documentation
- Constitute an award criterion
- Support or complement the SOA qualification pathway
What Are ISO Certifications?
- International standards defining system-level requirements, i.e. organisational, managerial, and procedural arrangements adopted by a company.
They do not certify the economic or technical capacity to execute a specific project, but rather how the organisation is structured and how key processes are managed. - Nature: Voluntary
- Scope: Management systems (quality, environment, health and safety)
- Applicability: All productive sectors
- Validity: 3 years, with periodic surveillance audits
- Benefit: Often rewarded in public tender evaluations
What Is SOA Qualification?
SOA qualification—more precisely referred to as SOA attestation—is entirely different in nature from ISO conformity certification.
- Mandatory by law for companies seeking to participate in public works tenders exceeding €150,000
- Scope: Certification of technical and financial capacity for specific work categories (OG and OS)
- Sector: Public procurement
- Validity: 5 years, with mandatory review in the third year
- Benefit: Eligibility to participate in public tenders
SOA attestation is issued by private certification bodies authorised and supervised by ANAC.
It is based on verified factual evidence and documentary proof, not on the implementation of standardised management processes.
Verifications Required for SOA Qualification
SOA qualification—more precisely referred to as SOA attestation—is entirely different in nature from ISO conformity certification.
- Mandatory by law for companies seeking to participate in public works tenders exceeding €150,000
- Scope: Certification of technical and financial capacity for specific work categories (OG and OS)
- Sector: Public procurement
- Validity: 5 years, with mandatory review in the third year
- Benefit: Eligibility to participate in public tenders
SOA attestation is issued by private certification bodies authorised and supervised by ANAC.
It is based on verified factual evidence and documentary proof, not on the implementation of standardised management processes.
ISO Certifications in the Construction Sector
ISO 9001
Quality management systems: organisational processes, customer satisfaction, continuous improvement.
ISO 14001
Environmental management: environmental impact, sustainability, regulatory compliance.
ISO 45001
Occupational health and safety: accident prevention, risk management, worker wellbeing.
ISO 37001
Anti-bribery management systems: measures and controls to prevent, detect, and address corruption.
ISO 39001
Road traffic safety management: reducing the risk of traffic-related incidents linked to organisational activities.
Other Regulatory Protocols
These standards do not replace SOA qualification for public works. They may be required as additional criteria or awarded as bonus elements in specific tenders.
LEED
Environmental and energy sustainability certification for buildings.
USA / Globale
BREEAM
Assessment of environmental performance and wellbeing in buildings.
UK / Europa
ENVISION
Sustainability rating system for infrastructure projects.
USA / Globale
SA 8000
Social accountability, labour ethics, and human rights in organisations.
USA / Globale
WELL
Health and wellbeing of occupants within buildings.
USA / Globale
FITWEL
Design and management of spaces promoting healthy lifestyles.
USA
Legislative Decree 231/2001 (Model 231)
Prevention of administrative offences and corporate liability.
Italia
ITACA Protocol
Environmental sustainability and energy efficiency specific to the Italian construction sector.
Italia
ESG Certification
Corporate performance in Environmental, Social, and Governance dimensions.
Globale
A Practical Example
- ISO 9001 certifies how a company manages its internal processes; it does not prove that the company has built a specific infrastructure
- SOA OG1 qualification demonstrates, through verified documentation, that the company has actually constructed buildings of a certain value, supported by valid Work Completion Certificates (CELs); it does not describe internal management processes
- LEED certifies that a building meets sustainability standards; it says nothing about the contractor’s minimum legal requirements or execution capacity
These instruments are complementary, not alternative.
Together, they describe how a company operates, what it is capable of delivering, and the level of quality and sustainability it brings to construction sites.
