Key points of safety management in confined space operation;
1. Safety isolation
All pipes and holes connected with the outside world on the equipment shall be effectively isolated from the outside world. The power supply connected to the outside world on the equipment should be effectively cut off.
The pipeline can be safely isolated by inserting a blind plate or removing a section of pipeline, and it is impossible to replace the blind plate or remove the pipeline with water seal or valve.
Remove the power fuse or pull down the power switch and lock it, and hang a warning sign, which can effectively cut off the power.
2 Cleaning and replacement
Before entering the confined space for operation, the space must be cleaned and replaced, and the following requirements must be met: 5.2. 1 oxygen content shall not be lower than that specified in Safety Regulations for Hazardous Operation in Oxygen Deficiency (GB 8958), and it shall also meet the requirements of Safety Regulations for Operation in Confined Space of Chemical Production Equipment (AQ 3028). 5.2.2 The concentration of toxic and harmful substances shall comply with the provisions of GBZ 2.
The concentration of combustible gas shall meet the requirements of Safety Code for Hot Work of Chemical Production Devices (AQ 3023).
Pay attention to the dead angle in the closed space when replacing and cleaning, and the pressure of replacing with steam or inert gas should not exceed the normal working pressure of equipment and containers.
Cleaning and replacement of confined space shall strictly comply with the company's relevant environmental management regulations to avoid negative environmental impact.
3 ventilation
When working in a confined space, measures should be taken to maintain good air circulation in the confined space.
Open all manholes, handholes, material holes, air doors, smoke exhaust doors and other facilities connected with the atmosphere for natural ventilation. If necessary, forced ventilation can be used.
When using pipeline to supply air, the medium and wind source in the pipeline must be analyzed and confirmed before ventilation. 5.3.4 It is forbidden to fill the confined space with oxygen or oxygen-enriched air.
4. Job monitoring
The guardian is generally designated by the maintenance operation unit. If necessary, the professional guardian of the unit or company where the equipment is located can be invited for guardianship.
The guardian should be familiar with the environment and technology in the operation area, have the ability to judge and deal with abnormal situations, know first aid knowledge and be familiar with emergency rescue methods.
The guardian shall confirm the implementation of the protective measures for the staff entering the confined space.
The guardian must count the number of workers entering and leaving the confined space before and after the operation. During the operation, contact signals must be determined with the operators, and contact with the operators must be maintained at the entrances and exits. It is forbidden to leave your post without permission and do things unrelated to guardianship.
When it is necessary to carry out rescue in a confined space, the guardianship and ambulance personnel must do their own protection before entering the confined space.
When the guardian finds that the safety measures have not been implemented or are not perfect, he must stop the operation in time.
5 Safety operation requirements
Work in confined space must be carried out with a safety license for confined space work.
When working in a closed space that can't meet the requirements of cleaning and replacement, reliable protective measures must be taken and supervised by professional guardians.
In oxygen-deficient and toxic environment, isolated gas masks should be worn, and filter gas masks are strictly prohibited. If you need to wear a long tube mask, contact the protective equipment management department to provide it.
In flammable and explosive environment, non-sparking explosion-proof low-voltage lamps and tools should be used, and chemical fiber fabrics are not allowed.
Wear anti-corrosion protective gear in corrosive environment such as acid and alkali.
The use of temporary power supply for confined space operation shall comply with the relevant provisions of the Power Supply and Demand Management System (Q/YYTH 20200).
When using hand-held electric tools that exceed safe voltage's or carrying out welding operations, leakage protectors must be equipped as required. In a wet container, the operator should stand on the insulation board and check whether the metal container is reliably grounded.
Safety ladders or safety platforms should be set up when high or multi-storey crossing operations are carried out in a limited space. If necessary, the guardian should tie safety ropes to the operators for construction.
When working at heights in confined spaces, the safety management regulations for working at heights shall be implemented.
Hot work in confined space shall be carried out in accordance with the Management System for Hot Work in Safe Production.
Materials, tools and other items shall not be thrown during operation, and measures shall be taken to prevent workers from being injured by falling objects between layers during cross operation.
The entrance and exit of the confined space should be kept unobstructed. Workers are forbidden to take off their protective masks in toxic and suffocating environments.
The operator shall enter the confined space for operation within 30 minutes after the workspace analysis is qualified. If it exceeds 30 minutes, it must be reanalyzed and confirmed to be qualified before entering the confined space for operation. Continuous operation should be monitored regularly, at least once every 2 hours.
Air respirator (oxygen respirator), fire fighting equipment, clean water source and other corresponding first-aid articles shall be provided outside the confined space.
When working in a confined space, if the operator feels uncomfortable, he should stop working and quickly return to the outside of the equipment, and must not insist on working.
Before and after the operation, the working instruments should be counted. When the operator leaves the operation point in the confined space, he should take out the operation tools and instruments.
In the process of confined space operation, due to the change of process conditions and working environment conditions, it is necessary to apply for a new permit before continuing the operation.
6. Management of work safety license in confined space
The operation applicant holds the task book (work ticket and work order) to handle the Safety Permit for Operation in Confined Space, fill in the basic information of the operation, and submit it to the person in charge of the operation to identify the operation hazards and put forward the safety measures to be taken.
The operation applicant shall, with the Safety Permit for Operation in Confined Space filled in, go to the leader or authorized person of the equipment transfer unit and the authorized person of the safety management department for approval in turn. After examination and approval, the team leader shall confirm the conditions for handing over the equipment.
After the equipment handover conditions are confirmed, the person in charge of the operation will go to the job site to confirm that the safety measures have been put in place, and conduct safety disclosure (education) for the operators, and at the same time contact the analysts for sampling and analysis. The sampling and analysis of confined space shall be carried out in accordance with the Safety Specification for Closed Space Operation of Chemical Production Devices, and the analysts shall be responsible for the analysis results, make records and sign for confirmation.
Operators should understand the relevant safety requirements and precautions in the process of confined space operation, check and confirm the implemented safety measures, and sign in the column of operators before operation.
Personnel working in confined spaces should carry the Safety Permit for Working in Confined Spaces with them for inspection by inspectors. After the operation, the person in charge of confined space operation shall sign for acceptance, and submit the Safety Permit for Confined Space Operation to the operation unit for filing. After the outsourcing unit completes the operation, it shall submit the license to the operation project unit for preservation.
Hazard identification in confined space;
1. Before entering the confined space for operation, the operation department shall identify the hazards in the confined space according to the operation contents, and formulate corresponding operation procedures and safety measures.
2. The person in charge of the operation shall confirm the relevant safety measures of the Permit for Working in Confined Space one by one, and fill in the supplementary measures in the corresponding columns and confirm them.
Procedures for handling work permit in confined space:
1. The department entering the confined space applies for the "Permit to Enter the Confined Space".
2. The person in charge of the operation department shall confirm and sign the operation procedures and corresponding safety measures. The "Permit for Operation in Confined Space" shall be issued and approved by the Minister of Safety and Environment, and in the absence of the Minister of Safety and Environment, it shall be issued and approved by the supervisor.
3. The person in charge of the operation department and the safety supervisor shall disclose the operation procedures and safety measures to the operators, designate the operation guardian, and supervise the whole process of confined space operation on site.
4. After the confined space operation is completed, the person in charge of the operation shall cooperate with the operation guardian to carry out the completion acceptance, and sign in the completion acceptance column of the Confined Space Operation Permit.