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-

  1. identified the possible major accident hazards; and
  2. 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
  3. 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.