10 Tips for Safe Management of Confined Spaces

Thread Content

1. The “Five Provisions for Safe Work in Confined Spaces” (Order No. 69): The “Five Musts and Five Prohibitions” are as follows: First, it is necessary to strictly implement an work approval system; entering confined spaces for work without authorization is strictly prohibited； Secondly, it is necessary to follow the order of \"ventilation first, then testing, and finally work\"; working without proper ventilation or testing is strictly prohibited ； Third, personal protective equipment against poisoning and suffocation must be provided, safety warning signs must be installed, and it is strictly prohibited to carry out operations without such protective measures ； Fourth, safety training must be provided to the workers; it is strictly prohibited for those who have not passed the training to start working ； Fifth, emergency measures must be established, emergency equipment must be available on site, and blind attempts at rescue are strictly prohibited. 2. Site supervisors, guardians, emergency rescue personnel, and workers involved in or engaged in work in confined spaces (referred to as the “four types of personnel for confined spaces”) must receive specialized safety training for working in confined spaces. Special safety training for confined spaces should have dedicated training records, which must be signed by the participants. Persons who have not received specialized safety training and passed the assessment shall not be engaged in confined space management or operations. 3. Teams engaged in work in confined spaces involving flammable and explosive substances, toxic and harmful gases, and low-oxygen environments should conduct a risk awareness training session for such work on a quarterly basis, and promptly improve the relevant work standards. 4. A confined space refers to a space that is enclosed or partially enclosed, isolated from the outside world, has narrow entrances and exits, does not allow workers to remain inside for long periods of time, has poor natural ventilation, and is prone to the accumulation of toxic, harmful, flammable, or explosive substances or to insufficient oxygen levels. Work activities carried out in confined spaces are referred to as confined space operations. 5. Confined spaces are mainly divided into three categories: enclosed or semi-enclosed equipment, underground structures, and above-ground structures. Facilities that are not used for a long time or areas with poor ventilation, mines, dikes in special situations, and excavation work are considered confined spaces. 6. The “three types of confined spaces” that the company focuses on controlling refer to those involving flammable and explosive substances ； Confined spaces involving toxic, harmful, asphyxiating gases or oxygen-deficient environments ； Confined spaces with a risk of drowning or entrapment. 7. When using ducted air supply, the forced ventilation intake area should be located away from areas where toxic and harmful gases might be released unexpectedly. Before supplying air, the medium inside the ducts as well as the air source must be analyzed and verified to ensure that the air source is safe and reliable ； In confined spaces that require ventilation and lack on-site ventilation equipment, specialized ventilation systems such as fans and ductwork should be installed. 8. When it is necessary to work in a confined space with low oxygen levels, the requirements specified in the \"Safety Regulations for Work in Low-Oxygen Hazardous Environments\" (GB8958) must be followed, and mechanical ventilation should be employed during such work. 9. To safely isolate a pipeline, a blind flange can be inserted or a section of the pipeline can be removed; water seals or valve closures cannot be used as substitutes for blind flanges or removed pipeline sections. In other words, there are only two ways to achieve a reliable cut-off: one is by installing a blind flange, and the other is by removing a section of pipe. Methods other than this, such as closing valves and using water seals, do not constitute reliable means of isolation. 10. A hypoxic environment refers to an air condition in which the volume percentage of oxygen is below 19.5%. An oxygen-rich environment refers to an air environment in which the volume percentage of oxygen is higher than 23.5%. The maximum allowable concentration of hydrogen sulfide under normal conditions is 10 mg/m3, with a residence time of 8 hours. Operation can continue for an extended period when the CO content does not exceed 24 ppm (30 mg/m3). For more information on safety, please check the details on safe production in the gas news section of Feifan Gas Market.