GB9448-1999 replaces GB9448-1988
"GB9448-1999 welding and cutting safety" since the implementation of self-2000-5-1
Foreword
This standard is based on the American Standard ANSI / AWS Z49 . 1 "Welding and Cutting safe" to 9448 GB - 1988 "Welding and Cutting safe" for revision, on the technical elements equivalent thereto; following changes in specific technical content:
- This standard uses China's standards as a reference. Due to the differences in the standard systems, adjustments have been made to varying degrees in the part of the reference to the relevant technical content of the standard, and changes have also been made in the text description.
-- ANSI / AWS Z49 . 1 The duplicated and difficult-to-manipulate parts of "Safety in Welding and Cutting" have been appropriately deleted in connection with the actual situation in China.
——According to our country's actual situation, we have retained ANSI / AWS Z49 . 1 Technical content that does not exist in the Welding and Cutting Safety but exists in the original standard and proves to be effective and reasonable;
——This standard is mainly applicable to general welding and cutting operations, so it deletes the content and special safety requirements that are not related to the operation in the original standard, such as the design and installation details in the climbing operation and busbar system;
- According to the layout of technical content, this standard has added an appendix.
This standard has replaced GB 9448-1988 since the date of implementation .
Appendix A , Appendix B and Appendix C of this standard are all suggested hints.
This standard was proposed by the State Bureau of Machinery Industry.
This standard is under the jurisdiction of the National Welding Standardization Technical Committee.
This standard is mainly responsible for drafting units: Harbin Welding Research Institute.
The main drafters of this standard are: Pu Dongguang and Zhang Hao.
First paragraph general rules
1 range
This standard specifies the basic principles that must be followed to avoid personal injury and property damage during the welding and cutting operations.
This standard provides a basis for the safe implementation of welding and cutting operations.
2 reference standards
The provisions contained in the following standards are incorporated into this standard and constitute the provisions of this standard. At the time of publication, the editions indicated were valid. All standards will be revised and all parties using this standard should explore the possibility of using the latest version of the following standards.
GBJ87-1985 noise control design specifications for industrial enterprises
GB/T2550-1992 Rubber hose for welding and cutting Oxygen rubber hose
GB/T2551-1992 Rubber hoses for welding and cutting Acetylene rubber hoses
GB/T3609.1-1994 Welding eye and face protection
GB/T4064-1983 Guidelines for Safety Design of Electrical Equipment
GB/T5107-1985 Hose fittings for welding and cutting
GB7144-1985 Gas cylinder color marking
GB/T11651-1989 Labor protection articles selection rules
GB15578-1995 resistance welding machine safety requirements
GB15579-1995 Safety requirements for arc welding equipment Part 1: Welding power supply
GB15701-1995 welding protective clothing
GB16194-1996 Hygienic standard of welding fumes in workshop air
JB/T5101-1991 Cutting torch for gas cutting machine
JB/T 6968-1993 Portable Micro Welding Torch
JB/T 6969-1993 injection and suction welding torch
JB/T 6970-1993 Jet Suction Cutting Torch
JB7496-1994 Gas cylinder regulator for welding, cutting and similar processes
JB/T 7947-1995 Equal Pressure Torch, Cutting Torch
3 General
3.1 Equipment and Operation
3.1.1 Equipment conditions
All welding and cutting equipment used in operation must be in normal working condition. When there are safety hazards ( such as: lack of safety or reliability ) , they must be stopped and repaired by maintenance personnel.
3.1.2 operating
All welding and cutting equipment must be used in accordance with the manufacturer's operating instructions or procedures, and must also meet the requirements of this standard.
3.2 Liability
Managers, supervisors and operators have their own responsibility for the safe implementation of welding and cutting.
3.2.1 Manager
The manager must perform the necessary safety training for the personnel performing the welding and cutting operations and the supervisors. The training includes: safe operation of equipment, safe implementation of processes and emergency measures.
It is the responsibility of the manager to notify the person performing the operation in a suitable manner ( eg safety training and education, verbal or written instructions, warning signs, etc. ) about the hazards and consequences that welding and cutting may cause .
The manager must mark the areas that are allowed to be welded and cut, and establish the necessary safety measures.
The manager must specify the individual welding and cutting operation rules in each area. And ensure that each person involved is aware of the hazards involved and understand the appropriate preventive measures.
The manager must ensure that only approved and inspected equipment ( such as welding and cutting equipment, regulators, pressure regulators, welders, welding guns, and personal protective equipment ) are used .
3.2.2 Site management and safety supervisors
Site management and safety supervisors should be set up at the welding or cutting site. These supervisors must be responsible for the safety management of the equipment and the safe execution of the process. While implementing supervisory responsibilities, they can also assume other responsibilities, such as on-site management, technical guidance, and operational collaboration.
Supervisors must ensure:
- All types of protective equipment are used reasonably;
- Properly configure fire prevention and extinguishing equipment on site;
- Assign fire guards;
- The required hot work procedures are followed.
Where there is no need for fire alert personnel, supervisors must make final inspections after the completion of the hot work industry and organize the elimination of potential fire hazards.
3.2.3 operator
The operator must have the basic conditions required for the special operator and understand the hazards that may occur during the operation and the procedures applicable to controlling the hazardous conditions. The operator must use the equipment safely so that it does not pose a hazard to life and property.
Operators can only perform welding or cutting operations on the premise that the specified safety conditions have been met and on-site management and supervisor approval. The operator can perform welding or cutting continuously without any change in the conditions of approval.
4 Personnel and work area protection
4.1 Work Area Protection
4.1.1 equipment
Welding equipment, welding, cutting tools, cylinders, cable and other instruments to be placed and securely held in good order, so that it will not work or prejudice the past, persons in the vicinity.
4.1.2 warning sign
Welding and cutting areas must be clearly marked and must have the necessary warning signs.
4.1.3 Protective screen board
In order to prevent workers or other people in the vicinity from being exposed to radiation and splashing damage from welding and cutting arcs, use non-flammable or fire-resistant screens ( or screens ) to isolate and protect them.
4.1.4 Welding compartment
Where permitted, the welding site may be separated by a non-flammable screen or screen to form a welded compartment.
4.2 Personal protection
When selecting protective equipment according to GB/T 11651 , the following considerations should also be taken:
4.2.1 Eye and face protection
When the operator observes the arc, he must use a hood with a filter or a hand-held mask, or wear safety goggles, goggles or other accessories.
Suitable glasses. Support staff should also wear similar eye protection devices.
Masks and goggles must meet the requirements of GB/T 3609.1 .
For large-area observations ( such as training, presentations, demonstrations, and some automatic welding operations ) , a large-area filter window or curtain can be used instead of
Must use a single mask, hand cover or goggles. Window or curtain material must provide observers with a safe protective effect against arcing and fragmentation
Slag splash damage.
The lens shading number can be selected with reference to Table 1 .
Table 1 Selection Guide for Goggles Shade No.
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4.2.2 Body Protection
4.2.2 .1 Protective clothing
Protective clothing should be selected according to the specific welding and cutting operation characteristics. Protective clothing must meet the requirements of GB 15701 and provide sufficient protection area.
4.2.2 .2 Gloves
All welders and cutters must wear fire-resistant protective gloves. See Appendix C ( Appendix for tips ) for relevant standards .
4.2.2 .3 Apron
When the front of the body needs additional protection against sparks and radiation, durable fire-resistant aprons made of leather or other materials must be used.
4.2.2 .4 Leggings
When additional leg protection is required, fire-resistant leg guards or other equivalent equipment must be used.
4.2.2 .5 Shawls, capes and sleeves
During overhead welding, cutting, or other operations, leather or other fire-resistant sleeves or caps must be worn when necessary, or a cap of refractory texture can be worn under the hood to prevent head burns.
4.2.2 .6 Other protective clothing
When noise cannot be controlled within the permissible sound level specified in GBJ 87 , protective devices ( such as ear muffs, ear plugs or other suitable means of protection ) must be used .
4.3 Respiratory Protection Equipment
Means for utilizing the ventilation air pollution can not be reduced to allowable limits in the working area can not be implemented or such controls must use respiratory protection device, such as: long tube masks, masks and other (standards See Appendix C).
Ventilation 5
5.1 adequate ventilation
In order to ensure that workers work in a harmless atmosphere, all welding, cutting, brazing and related operations must be performed under adequate ventilation conditions ( including natural ventilation or mechanical ventilation ) .
5.2 Prevent smoke flow
Measures must be taken to prevent the operator from directly breathing the flue gas produced by the welding operation.
5.3 Implementation of ventilation
In order to ensure that the degree of contamination of welding fumes in the workshop air is lower than the value specified in GB 16194 , various ventilation means ( eg natural ventilation, mechanical ventilation, etc. ) may be used as required .
6 Fire Fighting Measures
6.1 Fire Responsibility
The fire protection responsibilities of welding operators, supervisors and management personnel must be clearly defined and a practical and safe fire prevention management system must be established.
6.2 The specified operating area
Welding and cutting should be carried out in areas designed, constructed ( or specially designated ) to reduce fire hazards . When welding or cutting operations are to be performed in a non-designated area due to special reasons, they must be inspected and approved.
6.3 Hot working conditions with flammable areas
Welding or cutting operations can only be carried out without fire hazards.
6.3.1 transfer artifacts
When conditions are met, the workpiece must first be moved to the designated safety zone for welding.
6.3.2 Transferring Fire Sources
When the workpiece is immovable, move all movable objects around the fire hazard to a safe location.
6.3.3 The workpiece and fire source cannot be transferred
When the workpiece and fire source cannot be transferred, measures must be taken to limit the fire source to prevent fire, such as:
a) The flammable floor should be cleaned and protected by means of spreading water, spreading wet sand, metal sheets or the like.
b) All openings or cracks in the floor shall be covered or sealed, or other measures shall be taken to prevent flammable objects under the floor from coming into contact with sparks that may fall from the openings. Similar measures should be taken for cracks or openings in the walls, open doors or windows that are open or damaged.
6.4 Fire Fighting
6.4.1 Fire Extinguisher and Water Sprayer
There must be adequate fire extinguishing equipment in the place where welding and cutting operations are performed. The configuration depends on the nature and quantity of flammable items on site. It can be a pool, sandbox, hose, fire hydrant or portable fire extinguisher. Where there is a sprinkler, the sprinkler must be ready for use during welding or cutting. If the welding site is very close to the automatic sprinkler, the sprinkler can be temporarily covered with a non-combustible thin material or damp cotton cloth as required. And this kind of temporary masking is to facilitate rapid demolition.
6.4.2 Fire alert personnel settings
Fire alert personnel should be set up at the following welding or cutting work sites and locations that may cause fire:
a) The flammable material in the building structure or material near the flammables is within 10m from the operating point .
b) Openings expose exposed flammable materials within a 10m radius of openings in walls or floors ( including concealed spaces in walls or floors ) .
c) a metal near the other side of the metal partition walls, walls, ceilings, roofs, etc. susceptible to radiation or heat to ignite combustibles.
d) On- board operations When working on tanks, decks, overhead frames and bulkheads, sparks and heat transfer through welding may cause fire in the compartments.
6.4.3 Fire alert duties
Fire alert personnel must undergo the necessary fire training and be familiar with fire emergency procedures.
The duty of fire alert personnel is to monitor the fire conditions in the work area; after the completion of welding or cutting, check and eliminate possible residual fires.
Fire alert personnel can assume other duties at the same time, but they must not interfere with their fire alert tasks.
6.5 Welding or cutting with flammable containers
When welding or cutting containers containing flammable substances, special safety measures must be taken and approved after strict inspections. Otherwise, it is forbidden to start work.
7 Safety requirements in enclosed spaces
Special measures are required when working in confined spaces.
Note: Closed space refers to a relatively narrow or restricted space, such as tanks, boilers, containers, cabins, and so on. "Closed" means poor ventilation due to structure, size, shape.
7.1 Ventilation in enclosed spaces
In addition to normal ventilation requirements, ventilation in enclosed spaces also requires the prevention of the accumulation of combustible mixtures and the enrichment of oxygen in the atmosphere.
7.1.1 The entry of personnel
Persons are prohibited from entering in enclosed spaces without good ventilation. If you want to enter, you must wear suitable air supply breathing equipment and be supervised by someone wearing similar equipment.
If necessary, before entering, test the toxic gas, combustible gas, harmful gas, and oxygen amount in the enclosed space and confirm that it is harmless before entering.
7.1.2 Nearby People
Proper ventilation in enclosed spaces must not only ensure the safety of welders or cutters, but also ensure the safety of all personnel in the area.
7.1.3 Use of air
The amount of air used for ventilation must be such that the concentration of harmful substances in the enclosed space is below the specified value.
The compressed air supplied to the respirator or breathing apparatus must meet normal breathing requirements.
The respirator compressed air line must be a dedicated line and must not be connected to other lines.
With the exception of air, oxygen, other gases or mixtures must not be used for ventilation.
Where welding, cutting, or related processes are performed in areas that are directly hazardous to life and health, forced ventilation, supplied breathing equipment, or other appropriate means must be used.
7.2 Use of equipment
7.2.1 Gas cylinders and welding power supplies
When welding and cutting are performed in an enclosed space, the gas cylinder and the welding power source must be placed outside the enclosed space.
7.2.2 Vent pipe
Pipes used for welding, cutting or local exhaust ventilation of related processes must be made of non-combustible materials. These pipelines must be regularly checked as required to ensure that they function stably, and no flammable residue is found on the inner surface.
7.3 Adjacent areas
When welding or cutting is carried out in the vicinity of a closed space and there is a danger within the enclosed space, one must be made aware of the dangerous consequences within the enclosed space and it is forbidden to enter such an enclosed space in the absence of the necessary protective measures.
7.4 Emergency Signal
When an operator enters a closed space from a manhole or other opening, he must have the means to provide rescue signals to outsiders.
7.5 Guardians of enclosed spaces
When working in an enclosed space, if there is a gas that is seriously endangering life safety, guardians must be installed outside the enclosed space.
The guardian must have the rescue measures to rescue or protect the inside staff in a state of emergency, and have the ability to implement rescue operations. They must at any time monitor the status of the workers inside and keep in touch with them, and prepare emergency equipment.
8 Public Exhibitions and Demos
When displaying and demonstrating welding and cutting operations in public places, besides safeguarding the personal safety of the operators, the audience must also be protected from the effects of arc, spark, electric shock and radiation.
9 warning signs
Where soot, gases, arcs, sparks, electric shocks, heat, radiation, and noise from welding and cutting operations may cause harm, a clear understanding of these hazards should be made available through the use of appropriate warning signs.
The second chapter special rules
10 oxygen gas welding and cutting safety
10.1 General requirements
10.1.1 Parts Contacted with Acetylene
All parts in contact with acetylene ( including instruments, pipes, accessories, etc. ) must not be made of alloys containing more than 70 % copper, silver, and copper ( or silver ) .
10.1.2 Isolation of Oxygen and Combustibles
Oxygen cylinders, cylinder valves, fittings, pressure reducers, hoses and equipment must be isolated from oil, grease, and other combustibles or explosives. Do not touch oil bottles or oxygen equipment with oily hands or gloves with oil marks.
10.1.3 Sealing test
When checking the airtightness of the air connection, it is forbidden to use an open flame.
10.1.4 Prohibited Use of Oxygen
Do not use oxygen instead of compressed air. Oxygen is strictly prohibited for dusting pneumatic tools, oil preheating furnaces, starting and moving internal combustion engines, blow-through pipes, clothes and workpieces, pressurizing for ventilation or the like. Oxygen jets must not be sprayed on surfaces with oil, greased clothing, or into fuel or other storage tanks.
10.1.5 Oxygen equipment
Gas cylinders, equipment, lines, or instruments used for oxygen are strictly prohibited for use with other gases.
10.1.6 Gas Mixing Accessories
Without permission, it is forbidden to install devices or accessories that may mix air or oxyg
A dumbwaiter is a small
freight elevator or lift intended to carry objects rather than people.
Dumbwaiters found within modern structures, including both commercial, public
and private buildings, are often connected between multiple floors. When
installed in restaurants, schools, kindergartens, hospitals, retirement homes
or in private homes, the lifts generally terminate in a kitchen.
The term seems to have been
popularized in the United States in the 1840s, after the model of earlier
"dumbwaiters" now known as serving trays and lazy Susans. The
mechanical dumbwaiter was invented by George W. Cannon, a New York City
inventor. Cannon first filed for the patent of a brake system (US Patent no.
260776) that could be used for a dumbwaiter on January 6, 1883. Cannon later
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A simple dumbwaiter is a movable
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[There is] ... great play between
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