1. Diploma in Occupational Safety and Health

2. refers to an area with limited means of entry and exit that is large enough for a person to fit into but is not designed for occupancy. any place, including any vessel, tank, container, pit, bund, chamber, cellar or any other similar space which, by virtue of its enclosed nature, creates conditions that give rise to a likelihood of an accident, harm or injury. Hazards in a confined space often include suffocation by gases which may be present but not visible, or submersion in liquids or free- flowing granular solids (for example, grain bins) 3. Confined space generally recognized as: has limited or restricted means of entry or exit; is large enough for a person to enter to perform tasks; is not designed or configured for continuous occupancy; and has the potential for a significant hazard to be present. 4. According to the OSHA (USA), a permit-required confined space (permit space) has the three characteristics listed above (which define a confined space) and one or more of the following: Contains or has the potential to contain a hazardous atmosphere Contains a material that has the potential for engulfing the entrant Has an internal configuration that might cause an entrant to be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross section Contains any other recognized serious safety or health hazards. 5. Factories and Machinery ( Safety , Health and Welfare) Regulations 1970 Regulation 13: 13. (1) Where any work has to be done inside any chamber, tank vat, pit, pressure or other vessel or other confined space in which dangerous fumes are liable to be present to such extent as to involve risk to any person being overcome thereby, such confined space shall, unless there is other adequate means of egress, be provided with a manhole: such manhole should be rectangular, oval or circular in shape, and shall not be less than sixteen inches wide or not less than eighteen inches in diameter if circular. 6. Factories and Machinery ( Safety , Health and Welfare) Regulations 1970 Regulation 13: 13. (2) no person shall be required or permitted to enter any confined space unless- a. all practicable steps have been taken to removes any fumes which may present and to prevent any ingress in fumes; b. It has been ascertained by a suitable test that the confined space is free from dangerous fumes: Provided that where such test cannot be carried out the person entering the confined space shall wear an efficient respiratory protective device suitable for the dangerous substance that may is to be expected and a suitable safety belt with attached life line of adequate dimensions leading to a convenient point outside the tank or vessel; and a. a reliable and competent person is stationed at the entrance to the tank or vessel to supervise the operations and to take such action as may necessary in any emergency. 7. The most common hazard seen in confined spaces is that of atmospheric hazards. This involves 2 types of hazard which are toxic hazard and explosive hazard. These affect air quality and present immediate hazards to health or life. Acceptable atmospheric conditions must be verified before entry, and must be monitored continuously while the space is occupied. 8. The oxygen concentration, the presence of toxic gases, and flammable material are the three conditions that must be monitored. 1. Oxygen concentration is considered safe if it is between 19.5% and 23.5% of the total atmosphere. 2. To protect against toxic gases, contaminants should not exceed the permissible exposure limits (PELs), which are set by OSHA . 3. Work also cannot continue if the concentration of a material reaches or exceeds 10% of its lower explosive limit. 9. Even if a tank or similar vessel initially is tested and found to contain breathable air, a hazard can develop during operations inside the tank if residues inside the tank can release toxic gas or vapor when disturbed or if accidentally ignited. Steel water tanks may have dangerously low oxygen concentration when the interior rusts. 10. Table 1: Percentage of oxygen in the air and it effect to human breathing: 11. Another hazard related to confined space is physical hazard. Caused by mechanical or physical obstruction present in the confined space. Fall Trip 12. To ensure that a confined space is safe, some question need to be asked and answer before allowing entry. 1. Are access and exit equipment such as ladders and steps in good working condition? 2. Has the confined space been properly purged of the toxic vapors and other toxic substances. 3. Are all lines that transport potentially hazardous substances into or through the confined space turned off and properly capped? 4. Are all moving equipment and moving parts of equipment in the confined space shut down and locked out? 5. Has proper ventilation (natural or mechanical) been provided? 13. 1. Appointment of a supervisor Supervisors should be given responsibility to make sure that the necessary precautions are taken, to check safety at each stage and may need to remain present while work is underway. 2. Suitability of the worker Experiences, training, claustrophobia, medical examination 3. Isolation Mechanical and electrical isolation of equipment is essential if it could otherwise operate, or be operated, inadvertently. If gas, fume or vapour could enter the confined space, you need to isolate the pipework. In all cases, a check should be made to ensure isolation is effective. 14. 4. Cleaning before entry. 5. Size checking Is it big enough to allow workers wearing all the necessary equipment to climb in and out easily, and provide ready access and exit in an emergency?. 6. Probation of ventilation Improved ventilation, mechanical ventilation, SCBA. 7. Testing of the inside air 8. Provision of special tools and lighting Non-sparking tools, extra low voltage equipment (less than 25V) 15. 9. Provision of breathing apparatus 10. Preparation of emergency arrangements 11. Provision of rescue harness 12. Communications