Limited space operation|Safety management should know 66

1. On September 29, 2014, the State Administration of Work Safety issued the “Five Provisions on Limited Space Safety Operations” (Order No. 69), which will be implemented as of the date of promulgation.

2. "Five Provisions for Safe Operation of Limited Space" (Order No. 69) "Five Musts and Five Prohibitions" Contents: First, the operation approval system must be strictly implemented, and it is strictly forbidden to enter the limited space without permission; second, it must be "first ventilated, retested" And after the operation, it is strictly prohibited to ventilate and test unqualified operations; third, it must be equipped with personal protective equipment such as anti-poisoning and suffocation, set safety warning signs, and strictly prohibit unprotected monitoring operations; fourth, safety training must be carried out for operators, and education and training are strictly prohibited. Unqualified work; fifth, emergency measures must be formulated, emergency equipment is equipped on site, and blind rescue is strictly prohibited.

3. The person in charge of the site, the guardian, the emergency rescuer, and the operator (referred to as “four types of personnel in limited space”) involved in or engaged in limited space operations shall conduct special safety training in limited space. Special safety training for limited space should have a special training record and be signed and confirmed by the participants. Personnel who have not passed the special safety training and passed the examination shall not engage in limited space management and operation.

4. Teams involved in flammable and explosive materials, toxic and harmful gases, and limited space operations in anoxic environments shall organize a limited space operation hazard-predictive training activity every quarter and improve the operating standards in a timely manner.

5. Limited space means: closed or partially closed, relatively isolated from the outside, narrower entrance and exit, workers can not work for a long time, natural ventilation is poor, easy to cause toxic and harmful, flammable and explosive substances accumulation or insufficient oxygen content space. Work activities that enter a limited space are called limited space operations.

6. The limited space is mainly divided into three categories: closed semi-enclosed equipment, underground construction (structure), and ground construction (structure). Long-term unused facilities or places with poor ventilation, mines, dikes under special circumstances and excavation operations are considered as limited space.

7. “Three types of limited space” for key control refers to: limited space involving flammable and explosive materials; limited space involving toxic and suffocating gases or anoxic environments; and limited space for danger of drowning or burial.

8. When using pipeline air supply, the forced air draft area should be set away from the area where toxic and harmful gas may be released abnormally. Before the air supply, the medium and wind source in the pipeline should be analyzed and confirmed to ensure the safety and reliability of the wind source; Space, in the absence of online ventilation equipment, should be equipped with special ventilation, fan and other ventilation facilities.

9. When entering a limited space operation with oxygen deficiency, it should comply with the “Safety Regulations for Hazardous Oxygen Operation” (GB8958), and mechanical ventilation should be adopted during operation.

10. Pipeline safety isolation can be done by inserting a blind plate or removing a pipe for isolation. It is not possible to replace the blind plate or remove the pipe with water seal or valve closing. That is to say, there are only two ways to reliably cut off: one is to insert a blind plate, and the other is to remove a pipe. Other methods such as closing valves and water seals are not reliable means of cutting off.

11. Anoxic environment means that the volume percentage of oxygen in the air is less than 19.5%. An oxygen-rich environment means that the volume percentage of oxygen in the air is higher than 23.5%. The maximum allowable concentration of hydrogen sulfide in the normal state is 10 mg/m3, and the residence time is 8 hours. When the CO content does not exceed 24 ppm (30 mg/m3), it can work for a long time.

12. Use an isolated breathing apparatus such as an air respirator or hose mask when working in a limited space with oxygen or toxic or hazardous gases. Filter masks are strictly forbidden and the operator should carry a lifeline if necessary.

13. When wearing a long tube respirator, carefully check the air tightness and prevent the long tube from being squeezed. The suction port should be placed at the upwind of fresh air and guarded by a special person.

14. When working in a flammable and explosive limited space, wear anti-static overalls, work shoes, explosion-proof low-voltage lamps and tools that do not generate sparks. When working in a limited space with corrosive media such as acid and alkali, wear protective clothing such as acid-proof overalls, work shoes, gloves, etc.

15. Entering the limited space with rotating equipment, you must go through the power outage procedure, cut off the power supply, and hang the warning signs such as “someone works, no closing” and “no start”.

Pits, rafts, trenches or holes in the limited space, and entrances and exits of the passages shall be provided with guard rails, covers and warning signs, and warning lights shall be provided at night.

16. Persons entering the limited space that is difficult to rescue, such as vertical type, cylindrical shape, cylindrical type, etc., and those who inspect and repair their internal operations must all attach a reliable and secure "safety rope" (lifeline), and the rope ends must be fixed. At the entrance to the limited space. This "safety rope" (lifeline) must not replace the seat belt that prevents falling from high altitude. The guardian should communicate through a protective cord attached to the operator.

17. In the welding of metal equipment and particularly wet work places, it is necessary to improve the degree of electrical insulation protection (such as the use of electric insulating boots, laying insulation boards, etc.), the body is not allowed to lean on the conductive objects when replacing the welding rod. Electrical facilities used in confined spaces, including power tools, ventilation, lighting, etc., should have leakage protection devices.

18. When the limited space is the original container for explosive liquids, gases, etc., explosion-proof flashlights or explosion-proof safety lights with a voltage of not more than 12V shall be used. The light transformers shall not be placed in the containers or on the containers.

19. The limited space lighting voltage should be less than or equal to 36V. Hand-held running lights must have insulated handles and metal shields. They should be operated in metal containers, humid environments, small containers, and places with explosion hazards. The voltage should be less than or equal to 12V.

20. Hydrogen sulfide poisoning: Hydrogen sulfide (H2S) is a colorless gas, smells like egg, and is easily soluble in water. It is a suffocating and highly toxic gas and is a strong neurotoxic substance. The specific gravity is larger than that of air, and it is easy to accumulate in low-lying areas such as urban sewage pipes, wells, septic tanks, and sewage pools with poor ventilation.

21. CO poisoning: CO is colorless, odorless, non-irritating, flammable, explosive and toxic. It can form an explosive mixture when mixed with air. It can cause combustion and explosion when exposed to open flame and high heat. Carbon monoxide is easy to bind to hemoglobin in blood. In the case of oxygen), the tissue is deprived of oxygen.

22. Nitrogen, under normal conditions, is a colorless, odorless, odorless gas and is generally non-toxic. The nitrogen content in the air is too high, causing hypoxia and suffocation. When the concentration of inhaled nitrogen is not too high, the patient initially feels chest tightness, shortness of breath, weakness and weakness; when inhaled at a high concentration, the patient can quickly stun, die due to breathing and heartbeat. When the oxygen concentration in the workplace air is less than 19.5%, an air respirator or a long tube mask must be worn.

23. Due to the limited space temporarily formed by equipment maintenance or construction work (such as pipes, dikes, potholes, etc.) that need to enter the manhole, the “Notice of Hazardous and Hazardous Factors in Limited Space” should be set on the site before the operation. Inform potential hazardous and hazardous factors, safety control measures and emergency rescue measures (including emergency rescue equipment and facilities that should be prepared, emergency calls) in limited space.

24. The main dangerous and harmful factors in limited space are: asphyxiating gases, toxic and harmful gases, anoxic, flammable and explosive substances, liquids, materials, electric shock, falling, rotating equipment, high temperature/low temperature, and other dangerous and harmful factors.

25. Limited space risk factor identification 8 aspects: First, the risk of poisoning or suffocation caused by toxic and harmful gas or anoxic environment; second, the risk of fire or explosion caused by combustible gas, liquid, solid and flammable and explosive substances Third, the danger of flooding caused by rising liquid level or falling into a liquid storage facility; fourth, the danger of burial or suffocation caused by solid collapse; fifth, the risk of twisting caused by the rotation of equipment; sixth, the risk of electric shock caused by wet environment. Seven is the danger of falling from a height or falling from a height; eight is other dangers such as temperature, noise, and corrosive chemicals.

26. Dangerous characteristics of three aspects of limited space operations: First, the operating environment is complicated; second, the risk is high, and the consequences of the accident are serious; third, it is easy to cause casualties due to blind rescue. The main cause of the increase in casualties caused by limited space operations is improper rescue. 50% of the deaths in the accident are rescue workers.

27. The toxic, suffocating and flammable and explosive gases that may be involved in the limited space operation are:

Toxic, harmful, flammable and explosive gases: gas (mainly toxic components are CO), hydrogen sulfide (H2S), methane (biogas, H4C), sulfur dioxide (SO2), ammonia (NH3), hydrogen (H2), oxygen (O2) ) Asphyxiating gases: nitrogen (N2), argon (Ar), carbon dioxide (CO2), and the like.

28. According to the potential danger of limited space and the severity of the consequences, the limited space should be divided into A, B, C and D for hierarchical control and grading approval.

(1) Class A: limited space operations that may cause injury or death to many workers; the unit shall be in charge of the approval of the factory leaders of production, equipment and engineering;

(2) Class B: Limited space operations that may cause death, serious injury or large and above accidents; the limited space operation involving flammable and explosive substances, toxic and suffocating gases or anoxic environment The person in charge of the production, equipment, and engineering departments shall approve the approval, and other types of limited space operations may be examined and approved by the supervisor of the operation area;

(3) Grade C: limited space operations that may cause minor injury or general accidents of the operator; if there are existing operating standards, the operating standards shall be strictly enforced; if there is no operating standard, the competent authority of the limited area shall approve the operation;

(4) Class D: The potential hazard and harmful factors in the limited space have been completely determined and effectively controlled. Limited space management may not be included without any of the following four conditions, but well-established and reliable operating standards must be established prior to operation. 1. The presence or potential of toxic and harmful gases; 2. the presence or production of materials that may bury the entrant; 3. the internal structure may trap the entrant; 4. the identified health and safety risks.

29. The "Limited Space Operation Safety Permit" shall not be altered. If it is necessary to modify it, it shall be confirmed by the issuer at the modification office. Each column should be filled in by the responsible person, and no one else can sign it. The limited space operation permit department and the license approval personnel shall be announced after the main responsible person of the unit has reviewed and issued and executed.

30. No personnel shall enter the limited space without proper ventilation and testing. The test should not be taken 30 minutes before the start of the work. If the operation is interrupted for more than 30 minutes, the operator should re-ventilate and pass the test before entering the limited space.

31. When the ventilation equipment is stopped, the oxygen content in the limited space is lower than 19.5% or higher than 23.5%, and the concentration of toxic and harmful gases is higher than the limits set by national standards or industry standards, the limited space operation must be stopped immediately. And check the operators, temporarily close the entrance and exit of the job site, waiting for the ventilation equipment to resume normal operation.

32. “Four regulations” for gas detection: one is to detect all possible dangerous gases; the other is to insert a detection gun from the vent; the third is to detect all parts (top, bottom, irregular shape); the fourth is if it is detected Hazardous gases or vapours should be ventilated and cleaned before testing again.

33. Test record 10 items: measurement date, measurement time, measurement location, measurement method, measuring instrument, field condition at the time of measurement, number of measurements, measurement results, measuring personnel and recording personnel, and signed by the testing personnel.

34. The safe replacement of the limited space involving flammable and explosive gases shall comply with the following requirements: first, the use of inert gas such as nitrogen and carbon dioxide, steam cleaning; second, the operator should ventilate with fresh air before entering or approaching, and continue Detect the oxygen content in the space.

35. The number of measurements or continuous monitoring should be maintained in the operation where the oxygen content may change, at least every 2 hours. If there is a significant change in the results of the monitoring analysis, the frequency of monitoring should be increased.

36. The person in charge, guardian, operator, emergency rescuer and other personnel engaged in the “three types of” limited space must have the following three conditions: First, qualified space safety knowledge assessment; second, emergency rescue equipment will be used. The third is to have on-site emergency rescue capabilities.

37. The limited space operations involving flammable and explosive substances, toxic and harmful gases and anoxic environment must strictly abide by the principle of “first ventilation, re-detection, and post-operation” (9 words in limited space operation). The detection indicators include three concentrations: oxygen concentration, concentration of flammable and explosive substances (flammable gas, explosive dust), and concentration of toxic and harmful gases. The test shall comply with the relevant national standards or industry standards.

38. 9-step method for safety control of limited space operations: hazard identification, safety access, safety isolation, safety replacement, safety inspection, safety protection, safety monitoring, safety operation, safety confirmation before operation.

39. Before the limited space operation, according to the safety analysis and assessment, corresponding emergency measures should be made for the emergency situations that may be encountered in the limited space, including the escape route and rescue method in the emergency situation of the operator, the life-saving facilities and fire-fighting equipment on the site. Wait.

40. Before the limited space operation, the person in charge of the site shall organize the safety guardian, emergency rescue personnel and operators to control the work items, work contents and operations in accordance with the “Conscious Space Hazardous and Hazardous Factors Notification Card” or the limited space safety management account. The process identifies the dangerous and harmful factors that may exist in the operation process, improves the limited space operation plan, and proposes organizational measures, technical measures, engineering measures and emergency measures to eliminate and control the hazards.

41. Before the limited space operation, the emergency rescue personnel and their responsibilities, emergency response and information communication methods should be clarified, and all personnel entering the limited space should be informed.

42. Before entering the limited space, it should be replaced by inert gas such as nitrogen, steam ejector cleaning, and then forced ventilation to eliminate or reduce toxic and harmful gases in the limited space. It is forbidden to use pure oxygen to ventilate the gas. The limited space is filled with oxygen or oxygen-enriched air. Oxygen poisoning and combustion explosions occur in an oxygen-rich environment.

43. The operation plan shall be examined and approved according to the procedure, and the person in charge of the site, the guardian, the emergency rescuer and the operator shall be clarified, and the operator shall be informed of the limited space operation plan and the dangerous and harmful factors and prevention and control measures that may exist at the job site. The person in charge of the site shall supervise the operator to prepare for the work according to the plan.

44. All limited space operations should be provided with special (part-time) safety guards. Class A and Class B limited space operations should be provided with full-time guardians; guardians should be staffed by experienced personnel, familiar with the environment and process conditions of the work area, Be aware of possible hazards and the impact of hazards on workers and understand first aid knowledge. Receive special safety training for limited space and pass the examination.

45. During limited space operations, the safety guardian must not leave the job site and maintain uninterrupted contact with the operator. The guardian supervises and inspects before the operator enters the limited space and during the operation: the degree of compliance with the operation permit procedure, the implementation of the safety measures, the detection of toxic and harmful gases and oxygen content, the procedures for stopping the power transmission of the equipment, and the warning signs. On-site energy power medium or toxic and harmful gas pipelines are reliably cut off or shut down, on-site environmental safety, ventilation, illegal investigation and investigation of hidden dangers, and emergency rescue facilities.

46. ​​Limited space operations must be carried out with reliable partitioning (isolation) measures to separate facilities and equipment that may endanger the safety of work, and spaces where toxic and hazardous substances are present, from the site of operation.

47. In the “three types of” limited space temporarily formed in unconventional operation activities such as maintenance and construction, the person in charge of the site, guardian, operator and emergency rescue personnel shall be clearly defined in the construction plan preparation stage. Conduct limited space special safety training for relevant personnel.

48. During the limited space operation, the holes, holes and doors of the equipment and facilities should be used for natural ventilation. If the natural ventilation method cannot meet the safety requirements, mechanical forced ventilation must be adopted. Under special circumstances, the operator should wear safe and reliable breathing. mask.

49. The limited space operation must apply for the “Limited Space Work Safety Permit”. In the limited space, the “High Safety Operation Certificate” is required for high-altitude operations, and the “Fire Safety Certificate” should be applied for the hot work.

50. Check the workers and tools before working in limited space. After the operation is completed, the person in charge of the job site and the guardian shall supervise, guide, supervise the operation personnel to clean up the site, check the tools, and evacuate the work site after confirming the error.

51. The limited space operation is “not allowed to be allowed”: first, it is not allowed to enter the limited space without permission, and the second is that the operation plan is not approved for safety and reliability, and the operation is not allowed. Third, the gas and oxygen-deficient environment is limited. The space is not taken through ventilation and continuous monitoring measures are not allowed to operate; the fourth is that the operation personnel are not allowed to perform the dangerous and harmful factors, and the operation is not allowed; the fifth is that the on-site safety measures are not confirmed by the special person; the sixth is that the safety guardian is not on site. No operation is allowed; seventh, qualified personnel are not allowed to work; eight is not completely cleaned up residues are not allowed to work; nine is emergency rescue measures and equipment preparation is not in place not allowed to operate; ten is workers, tools Unclear inventory is not allowed to close the entrance.

52. “10 musts” for limited space operations: First, the procedures for approval of safety licenses must be handled; second, reliable isolation (isolation) and replacement measures must be taken; third, the principle of first ventilation, re-detection, and post-operation must be implemented; Maintain the normal continuous operation of the ventilation facilities; fifth, the gas monitor must be worn; sixth, it must be equipped with communication tools, set up the safety guardian and keep in touch; seventh, it must work according to the operating standards and individual safety technical measures; Escape and emergency rescue channels must be set in the limited space; nine must keep the entrance and exit unimpeded; ten is that the abnormal situation must be evacuated immediately.

53. Gas-based limited space operation life support rules: First, the gas is reliably cut off (blocking the blind plate or removing a pipe, closing the valve, and locking the upper lock). Second, the purge and replacement before the operation, monitoring and passing. The third is continuous ventilation, timing or continuous monitoring during operation.

54. Life-saving rules for material-buried limited space operations: First, the source of materials is reliably isolated (interrupted) or thoroughly cleaned. Second, the incoming system is powered off and listed (the local switch hits the zero position and is listed), and the emergency facilities such as the belt system accident drawstring are in a self-locking state. Third, the operator uses safety ropes or seat belts and is securely fixed outside the limited space. It is strictly forbidden to stand under the storage facilities such as the barrel and silo.

55. Inflammable and explosive materials, limited space operation life support rules: First, flammable and explosive materials must be thoroughly cleaned and not allowed to be stored around the work site. The second is continuous ventilation, monitoring or filling if necessary.

56. Life support rules for drowning limited space operations: First, the liquid source is reliably cut off (close the valve, set the physical partition). Second, the operator uses seat belts or safety ropes and is securely fixed outside the limited space. Third, protective clothing should be used in the acid environment.

57. Life-saving rules for mechanical limited space operations: First, equipment and facilities must be powered off and listed, with obvious disconnection points, industrial safety locks when necessary; second, hardware measures to prevent equipment facilities from rotating; third, operators must The entrance and exit can be closed after all evacuation from the work site.

58. Five common misconceptions in the process of limited space operation: First, there is no danger of smelling or seeing any danger, and no problem is entered; second, only the probe goes in and looks at it, it is not really necessary to enter; the third is to go in quickly The fourth is checked, no problem, you can not test the instrument; fifth, once something happens, you can hold your breath and escape.

59. After the limited space workers are involved in the accident, the relevant personnel on the scene shall immediately report the police and prohibit blind rescue. When emergency rescue personnel implement rescue, they should do their own protection and wear necessary breathing apparatus and rescue equipment.

60. Limited space emergency supplies configuration requirements: Before carrying out limited space operations, emergency personnel should be equipped with full-face positive pressure air breathing apparatus or long tube mask and other isolated respiratory protection equipment, emergency communication alarm equipment, on-site rapid detection equipment, large Power forced ventilation equipment, emergency lighting equipment, safety ropes or lifelines and safety ladders.

61. Eight measures should be taken in the event of an emergency in the limited space operation process: first, call for help or alarm; second, wait for help before entering; third, open ventilation equipment while waiting; fourth, evacuate the injured person; fifth, artificial ventilation; It is to use rescue equipment as much as possible; seven is to organize medical care; eight is to isolate this area until the cause is found.

62. Emergency Center Tel: 120; Fire Alarm Phone: 119.

63. When there are multiple contractors in the same limited space, the centralized management department of each unit's outsourcing business shall designate a special person to coordinate and manage the safety production work of the contractor. The limited space operation is a subcontracted project, and the general contractor and the subcontracting unit shall simultaneously participate in the on-site written safety disclosure of the unit where the limited space is located.

64. Outreach personnel engaged in “three types of” limited space or operating in a limited space of Class A must be personnel who have worked in the units for at least three months.

65. The “four types of personnel” (site in charge, guardian, emergency rescuer, and operator) engaged in limited space management and operation must correctly use the C0 detector, oxygen content analyzer, air breathing apparatus, fire extinguisher, etc. And emergency rescue equipment.

66. Out-of-town personnel (including on-site supervisors, guardians, emergency rescuers, and operators) who work in limited space must be personnel who have been working for at least six months.