What is the difference between OHSAS 18001 and ISO 45001 and what are their benefits?

OHSAS 18001 and ISO 45001 are international standards that limit and prevent workplace accidents. They both seek to control hazards in operational contexts through risk management and legal compliance.

Developed by the Occupational Health and Safety Assessment Series Project Group, OHSAS 18001 was a widely used standard from March 1999 to March 2021. At the end of these more than two decades, the group composed of standardizing organizations from multiple countries adopted ISO 45001 in its place.

The International Organization for Standardization facilitated the migration of companies certified by OHSAS 18001 to an integrated management system or to ISO 45001. This way, they could maintain a valid certification.

Today we will talk about the difference between OHSAS 18001 and ISO 45001, what are the major innovations brought by the latest standard, and what are the benefits of implementing an occupational health and safety management system.

What was OHSAS 18001

Officially published in 1999 by the British Standards Institution (BSI), OHSAS 18001 was widely used worldwide since its creation. It played a very important role in improving regulations and requirements related to occupational health and safety.

Contrary to what many think, OHSAS 18001 is not part of the International Standards issued by ISO, but its nature and effects were similar to them. After all, the goal is to offer better and safer working conditions.

The standard was created at a time when organizations around the world recognized the need to control and improve the health and safety performance of work environments. OHSAS 18001 arrived in a context of increasing national standards and certification schemes, which caused confusion and fragmentation in the market.

The standard resolved this issue by creating a unified standard, but it began to demand updates as it approached two decades in activity. It was then that the International Organization for Standardization took the lead in the situation and developed ISO 45001, which ended up succeeding the OHSAS standard.

What is ISO 45001

The first global standard for Occupational Health and Safety Management Systems, ISO 45001 is based on other ISO management standards. Among them are ISO 9001 (Quality Management) and ISO 14001 (Environmental Management).

It is also based on other health and safety standards such as OHSAS 18001 and the International Labour Organization’s Guidelines — as well as labor standards and union conventions.

ISO 45001 uses a simple PDCA model that provides companies with a framework to plan what they need to put in place to minimize risks and harm to the health and safety of employees. The standard is based on the ISO High-Level Structure known as Annex SL, which divides its structure into chapters and sections.

Companies had until September 2021 to migrate from OHSAS 18001 to the new standard — a necessity to maintain an internationally credible occupational health and safety management system.

In general, ISO 45001 is more comprehensive than its predecessor, including requirements for leadership and worker participation. It also has a greater focus on preventing accidents and illnesses, rather than just identifying and controlling risks.

Differences between OHSAS 18001 and ISO 45001

ISO 45001 presents several advantages over OHSAS 18001. Firstly, ISO 45001 has a structure based on Annex SL, which aligns different management system standards and applies a common language to all of them.

Additionally, ISO 45001 is dynamic in all its clauses, making implementation easier and more efficient. The standard also requires the involvement of Top Management, resulting in greater leadership commitment to the OHS management system.

In the table below, you will find the main differences between OHSAS 18001 and ISO 45001:

Standard	OHSAS 18001	ISO 45001
Structure	Not based on Annex SL	Based on Annex SL
Implementation	Focused on procedures	Focused on processes
Risk Approach	Reactive (after unwanted events)	Proactive (before events)
Top Management Involvement	Not required	Required
Stakeholder Involvement	Not specified	Workers, suppliers, third parties, unions, owners, community, customers
Applicability	Specific procedures	Systemic view and interrelation of processes
Focus	Exclusively on risks	Risks and opportunities
Clause Dynamics	Less dynamic	More dynamic
Leadership Commitment	Lower	Higher
Organizational Culture	Less involvement	Everyone as transformative agents
Types and Sizes of Organizations	Less flexible	Applicable to all types and sizes, considering various circumstances

Innovations of ISO 45001

Now that you know the main differences between the two standards, let’s talk about what ISO 45001 brought as innovations in each of its clauses. There were seven new clauses in total, addressing everything from the organization’s context to improvement requirements.

Clause 4: Context of the Organization

Incorporates the general requirements (clause 4.1) of OHSAS 18001.

Includes two new sub-clauses:

Understanding the organization and its context;
Understanding the needs and expectations of interested parties.

Companies must understand the occupational health and safety challenges of the organization and the inherent risks in this segment.

It is also important to understand the internal and external environment to determine relevant issues that may hinder the success of the Occupational Health and Safety Management System implementation.

Finally, it is necessary to determine and analyze who are the interested parties.000

Clause 5: Leadership

The requirements such as Policy, Organizational Roles, Responsibilities, Assignments, and Authorities are all transferred from OHSAS 18001.

However, ISO 45001 included an important new requirement, leadership and worker participation:

Top Management must demonstrate its leadership and commitment by taking responsibility for the effectiveness of occupational health;
“Workers” include top management, managers, and non-managers;
Everyone must be included in the decision-making process.

Clause 6: Planning

This clause requires companies to consider the risks and opportunities associated with the issues identified in item 4.1. It seeks to replace preventive action and reduce the need for corrective actions.

The requirements on risks and hazards have been expanded, also focusing on risks and opportunities related to stakeholders that are relevant to the organization.

Some of the requirements of this clause can be implemented in the planning phase.

When planning the OHS management system, companies must consider:

Issues referred to in the Organizational Context (4.1);
Requirements referred to in Interested Parties (4.2);
Scope of their occupational health and safety management system (4.3);
Determine risks and opportunities that need to be addressed.

It is important to note that ISO 45001 differentiated “risks” from “OHS risks” in its terms and definitions section:

Risk: effect of uncertainty.

This term is strategic, aimed at the overall results of the management system and the company’s strategy.

OHS risk: combination of the likelihood of occurrence of a hazard or exposure to the hazard and the severity of the injury or illness that may be caused by the event or exposure.

This is the technical term equivalent to the former risk in OHSAS 18001. It is also equivalent to the “risk” referenced in the “risks and opportunities” section of ISO 45001.

Clause 7: Support

The requirements of this clause take into account the areas of:

Resources;
Competence;
Awareness;
Communication;
Documented information.

The organization must manage and maintain documented information on health and safety objectives and plans. All data must be available and adequate for workers to have a clear view of work hazards and risks.

It is worth noting that “Documents and records” has been replaced by “Documented information.”

Clause 8: Operation

There are no significant changes here, just more specific and explicit items compared to OHSAS 18001.

It includes the requirements of:

Operational Planning and Control;
Change Management;
Outsourcing;
Procurement;
Emergency Preparedness and Response Plans.

Organizations must control outsourced processes that affect health and safety management systems. They must also ensure that the procurement of goods and services complies with the requirements of the OHS management system.

Clause 9: Performance Evaluation

With the ISO standard, you need to consider the requirements of:

Monitoring;
Analysis and Evaluation;
Compliance Evaluation;
Internal Audit;
Management Review.

Determine which different issues need to be monitored, measured, analyzed, and evaluated. Also decide how and when this should happen.

Establish, implement, and maintain a process for monitoring, measuring, and evaluating the performance of the OHS management system.

Clause 10: Improvement

Completing our list, clause 10 (Improvement) considers requirements of:

Incidents;
Nonconformities;
Corrective Actions;
Continuous Improvements.

Note: Preventive Actions are no longer a requirement of the standard.

Are you interested in learning more about ISO 45001 after reading this article? Then I invite you to check out other content we have already prepared on this topic!

Conclusion

The transition from OHSAS 18001 to ISO 45001 marked an advance in occupational health and safety management, bringing a more proactive and integrated approach to the current challenges of organizations. While OHSAS 18001 played a fundamental role in standardizing and improving safety practices, ISO 45001 raised the bar by including leadership participation, a systemic view, and an expanded focus on risks and opportunities.

By adopting ISO 45001, companies not only ensure compliance with a recognized international standard but also promote a safer and more sustainable work environment. The active involvement of all levels of the organization reinforces a safety culture that benefits workers, leaders, and the community as a whole.

If your company has not yet migrated to ISO 45001, this is the ideal time to evaluate the benefits of adopting a robust occupational health and safety management system. Count on SoftExpert to be in full compliance with ISO standards!

Looking for more efficiency and compliance in your operations? Our experts can help identify the best strategies for your company with SoftExpert solutions. Contact us today!