Demonstration Of Safe Operation (DOSO) assessment is for non-major hazard installation as stipulated in Occupational Safety and Health (Control of Industrial Major Accident Hazards) Regulations 1996 or CIMAH regulations. DOSO is applied to an industry activity where the hazardous substance in the CIMAH regulations is less than the specified threshold quantity and more than 10% of the threshold quantity.
A manufacturer who falls under DOSO shall, at any time, show that he has-
- identified the possible major accident hazards; and
- taken adequate steps to:
- prevent any major accident or minimize its consequences to persons and the environment; and
- provide persons working on the site with the information, training, and equipment necessary to ensure their safety; and
- prepared and kept up to date an adequate on-site emergency plan detailing how major accidents will be dealt with.
The content of the DOSO safety report shall be in accordance to the requirements of Schedule 6, CIMAH Regulation 1996. The main elements of the report are as follows:
Information relating to every hazardous substance involved in the industrial activity and its relevant quantity as listed in Schedule 2 of the CIMAH regulations, namely:
- The name of the hazardous substance as given in Schedule 2 or, for a hazardous substance included under a general designation, the name corresponding to the chemical formula of the hazardous substance;
- A general description of the analytical method available to the manufacturer in determining the presence of the hazardous substance or references to such method in the scientific literature;
- A brief description of the hazards which may be created by the hazardous substance; and
- The degree of purity of the hazardous substance, the names of its main impurities and their percentages;
Information relating to the installation, namely:
- A map of the site and its surrounding area to a scale large enough to show any feature that may be significant in the assessment of the hazard or risk associated with the site;
- A scale plan of the site showing the locations and quantities of all significant inventories of the hazardous substance;
- A description of the processes or storage involving the hazardous substance and an indication of the conditions under which it is normally held;
- The maximum number of persons likely to be present on the site;
- Information about the nature of the land use and the size and distribution of the population in the vicinity of the industrial activity to which the report relates; and
- Information on the nearest emergency services (fire station, hospital, police station, community hall, etc.);
Information relating to the system of management for controlling the industrial activity, namely:
- The staffing arrangements for controlling the industrial activity with the name of the person responsible for safety on the site and the names of the persons who are authorised to set emergency procedures in motion and to inform outside authorities;
- The arrangements made to ensure that the means provided for the safe operation of the industrial activity are properly designed, constructed, tested, operated, inspected and maintained; and
- The arrangements for training persons working on the site; and
Information relating to a potential major accident in the form of consequence assessment which contains the following:
- A description of the potential sources of a major accident and the conditions or events which could be significant in giving rise to one;
- A diagram of the plant in which the industrial activity is carried on sufficient to show the features which are significant as regards the potential for a major accident or its prevention or control;
- A description of the measures taken to prevent, control or minimise the consequences of a major accident;
- Information about the prevailing meteorological conditions in the vicinity of the site;
- An estimate of the number of people on-site and off-site who may be exposed to the hazards considered in the report; and
- The consequences to the surrounding areas in the form of appropriate mitigation measures where possible.
Although DOSO requirement may not be from a major hazard installation but if it is next to a major hazard installation, it could be a potential initiating event of major accidents to its neighbor, hence why care must be taken for DOSO site so as to minimize the impact to the people onsite and offsite.
A HSE Management System is an integrated approach where all the 3 HSE factors are effectively managed to reduce risks in the workplace and environment. The objective of a HSE Management System is to provide a structured management approach to control health, safety and environmental risks.
International standard ISO 45001:2018 Occupational Health and Safety Management Systems lists down requirements with guidance for use. ISO 14001;2015 Environment Management Systems sets out the criteria for an environmental management system.
Regardless of the industry you are in, all organisations need a comprehensive, well-documented HSE management system to ensure that all personnel are safe and environment are protected. A HSE management system must be written down, communicated and practised.
The key elements of a successful HSE management system include:
- HSE plan and inspection checklists
- Risk assessments and monitoring
- Training and induction
A HSE plan is a strategic action plan which sets out all current and prospective risks for the company. It provides an analysis of all risks present, with an outline of how to remove said risks. This HSE plan helps to set up a framework for all workers to follow and be held accountable to maintain the HSE record of the workplace. A HSE plan also comprises of HSE inspection checklists and emergency response plans.
Risk assessments document all risks in the workplace. This helps in protecting all workers and surrounding people from potential hazards. All areas of HSE non-compliance are outlined in the assessment and aid in ensuring proper solutions are in place. After risk assessment, risk monitoring is to be conducted depending on the risk level to maintain HSE in place.
Reporting of HSE elements is needed to monitor the performance of HSE elements. HSE key performance indicators (KPI) are needed to measure the performance of the HSE aspects. These KPI help to identify areas that need improvement. KPI for HSE include Lost Time Injury (LTI), number of accidents and incidents, productive days, near misses, etc.
All workers need to receive adequate training on the various HSE rules and procedures at the worksite. A thorough training program includes all HSE aspects e.g. PPE training, fire drills, scheduled waste management, management of pollution control equipment, etc. These trainings must be recorded to keep track of the training to ensure a successful HSE management system. In conclusion, the management plays a critical role in making HSE management system a success.
Layer of Protection Analysis also known as LOPA is a risk management technique commonly used in the chemical process industry that can provide a more detailed, semi-quantitative assessment of the risks and layers of protection associated with hazard scenarios. LOPA is a means to identify the scenarios that present the most significant risk and determine if the consequences could be reduced by the application of inherently safer design principles. LOPA can also be used to identify the need for safety instrumented systems (SIS) or other protection layers to improve process safety.
LOPA is a risk assessment methodology which uses simplified, conservative rules to define risk as a function of both frequency and potential consequence severity. LOPA is defined as a simplified risk assessment of a one cause – one consequence pair.
Conceptually, LOPA is used to understand how a process deviation can lead to a hazardous consequence if not interrupted by the successful operation of a safeguard called an independent protection layer (IPL). An IPL is a safeguard that can prevent a scenario from propagating to a consequence of concern without being adversely affected by either the initiating event or by the action (or inaction) of any other protection layer in the same scenario.
Examples of IPLs are as follows:
- Standard operating procedures,
- Basic process control systems,
- Alarms with defined operator response,
- Safety instrumented systems (SIS),
- Pressure relief devices,
- Blast walls and dikes,
- Fire and gas systems, and
- Deluge systems.
LOPA can be used at any point in the lifecycle of a project or process, but it is most cost effective when implemented during front-end loading when process flow diagrams are complete and the P&IDs are under development. For existing processes, LOPA should be used during or after the HAZOP review or revalidation. LOPA is typically applied after a qualitative hazards analysis has been completed, which provides the LOPA team with a listing of hazard scenarios with associated consequence description and potential safeguards for consideration.
The six major steps to the LOPA process are as follows:
- Record all reference documentation
- Document the process deviation and hazard scenario under consideration by the team
- Identify all of the initiating causes for the process deviation and determine the frequency of each initiating cause
- Determine the consequence of the hazard scenario
- List the IPLs that can completely mitigate all listed initiating causes
- Provide specific implementable recommendations
There are four primary benefits to implementing LOPA over other SIL assignment methodologies procedures.
- Due to its scenario-related focus on the process risk, LOPA often reveals process safety issues that were not identified in previous qualitative hazards analysis.
- Process hazards are directly connected to the safety actions that must take place, providing clear identification of the safety instrumented systems and associated SIL.
- It has been proven effective in resolving disagreements related to qualitative hazards analysis findings.
- LOPA often identifies acceptable alternatives to the SIS, such as adding other layers of protection, modifying the process, or changing procedures. This provides options for the project team to evaluate using cost/benefit analysis, allowing the most cost effective means of risk reduction to be selected.
In conclusion, LOPA allows the safety review team an opportunity to discover weaknesses and strengths in the safety systems used to protect employees, the plant, and the public.
Quantitative Risk Assessment (QRA) is to evaluate risks in ensuring that major risks of facilities are understood and managed within ALARP.
QRA makes sure that:
- The hazards and the associated risks inherent in the design and operations are systematically identified and assessed.
- Basis to demonstrate safety has been identified and incorporated in the design.
- Arrangements are in place to manage these risks to ALARP.
QRA is a quantitative risk assessment approach which shall provide information on the following:
- Identification of hazards and potential hazardous events
- Estimation of likelihood, causes, possible escalation and consequences of hazardous events and the adequacy of the mitigation measures
- Identification of the dominating risk contributors and appropriate risk reduction, if applicable, which can potentially reduce the risk“>risk
- Demonstration of risk to as low as reasonably practicable (ALARP) in accordance to risk acceptance criteria.
QRA also supports statutory compliance under the Control of Industrial Major Accident Hazards (CIMAH) 1996 Regulations by Malaysian Government Department of Occupational, Safety and Health (DOSH), and HSE Case for upstream facilities.
QRA study/review shall be carried out throughout the full lifecycle of project, facilities and operation:
- Design Stage
- Operations Stage
The QRA shall be reviewed as follows:
- Onshore facilities – every three (3) years as part of CIMAH report review for Major Hazard Installation.
- Offshore facilities – every five (5) years as part of HSE Case review.
- Significant changes or modification to the project, facilities and operations that has the potential to introduce new hazards.
Among the common software used for the risk modelling and analysis:
- TNO Effects and Riskcurves
QRA is important to determine the risk of a facility whether it is acceptable or not hence it is important for the facility owner to conduct QRA to ensure the safety of the facility workers, surrounding people, and the environment.