EN_NR_34_SOLDA_REV._00.pdf

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1. NR-34 COND. OF WORKING ENVIRONMENT IN THE CONSTRUCTION, REP. AND NAVAL DISMANTLING INDUSTRY - WELDING
2. INDEX AIM RISK OF ELECTRIC WELDING ESTIMATED EFFECTS OF ELECTRIC SHOCK ELECTRICAL PROTECTION IONIZING RADIATION WELDING CABLES INTRODUCTION
3. RISKS IN WELDING WITH SPECIAL PROCESSES (SUBMERGED ARC, MIG, MAG TIG) METAL GASES AND FUMES EPI E EPC
4. INTRODUCTION FOR THE PURPOSES OF THIS STANDARD, HOT WORK IS CONSIDERED TO BE WELDING, GOUGING, GRINDING, CUTTING OR OTHER ACTIVITIES THAT MAY GENERATE SOURCES OF IGNITION SUCH AS HEAT, SPARKS OR FLAMES. PROTECTION MEASURES INCLUDE GENERAL AND SPECIFIC MEASURES, APPLICABLE, RESPECTIVELY, TO ALL ACTIVITIES INHERENT TO HOT WORK AND WORK IN AREAS NOT PREVIOUSLY DESIGNATED FOR THIS PURPOSE.
5. AIM COMPLY WITH NR-34, WHICH IS REGULATED BY ORDINANCE NO. 200 OF JANUARY 20, 2011, AMENDED BY ORDINANCE SIT NO. 317 OF MAY 8, 2012 AND UPDATED BY ORDINANCE MTE NO. 1,897 OF DECEMBER 9, 2013, AIMING TO PROVIDE PARTICIPANTS WITH THE NECESSARY INFORMATION REGARDING MEASURES TO PROTECT SAFETY, HEALTH AND THE WORK ENVIRONMENT IN THE ACTIVITIES OF THE SHIPBUILDING AND REPAIR INDUSTRY, WITH A FOCUS ON ACTIVITIES INHERENT TO HOT WORK.
6. RISK OF ELECTRIC WELDING ELECTRIC WELDING IS THE PROCESS OF HEATING AND WELDING TWO PIECES OF METAL TOGETHER USING A POWERFUL ELECTRIC CURRENT. IT WAS INVENTED BY PROFESSOR ELIHU THOMSON. IT REQUIRES THE USE OF A SPECIALIZED DEVICE CALLED A DYNAMO THAT DELIVERS THE CURRENT USED FOR WELDING. TO BEGIN WITH, ELECTRIC ARC WELDING IS A PROCESS THAT JOINS METALS BY HEATING THE PIECES. THIS OCCURS THROUGH A CONTINUOUS ELECTRIC DISCHARGE, WHICH CREATES THE ARC THAT GIVES THIS TYPE OF WELDING ITS NAME. BASICALLY, THE ELECTRIC ARC MELTS THE MATERIAL BEING WORKED ON TO FORM THE JOINT. WELDING STAINLESS STEEL (HEXAVALENT CHROME) CR(VI) IS A HIGHLY TOXIC SMOKE AND CAN CAUSE DAMAGE TO THE EYES, SKIN, AIRWAYS AND LUNGS, WITH A RISK OF CANCER. WORKERS' EXPOSURE LIMITS TO CR(VI) ARE REGULATED BY BODIES SUCH AS ABNT, OSHA, ISO, AMONG OTHERS.
7. STILL ABOUT WELDING ACTIVITY, THERE ARE SOME RISKS THAT YOU NEED TO BE AWARE OF, THESE ARE: INHALATION OF HAZARDOUS FUMES AND PARTICLES WORKING IN AN UNCOMFORTABLE POSTURE AND LIFTING HEAVY ITEMS EXPOSURE TO VIBRATIONS, SUCH AS VIBRATIONS FROM GRINDING AND SLAG REMOVAL TOOLS EYE DAMAGE AND SKIN INJURY DUE TO UV FROM THE WELDING ARC. SPLASHES AND SPARKS IN THE EARS, EYES OR SKIN NOISE EXPOSURE COMING INTO CONTACT WITH ELECTRICALLY CONDUCTIVE EQUIPMENT AND RECEIVING AN ELECTRIC SHOCK SUFFER AN ACCIDENT, SUFFOCATION, POISONING, FIRE OR EXPLOSION EXPOSURE TO ELECTROMAGNETIC FIELDS FROM POWER CABLES AND WELDING EQUIPMENT
8. ELECTRIC SHOCK OCCURS WHEN ELECTRIC CURRENT TOUCHES THE BODY OR EVEN “TRAVELS” THROUGH IT, WHICH CAN HAPPEN DUE TO CONTACT WITH FAULTY APPLIANCES OR MACHINES, HOUSEHOLD WIRING, POWER LINES, SOCKETS AND EVEN LIGHTNING. IN SOME CASES, THE PERSON IS UNHARMED, BUT DEPENDING ON THE DISCHARGE, THEY CAN BE SERIOUSLY INJURED OR EVEN DIE. ACCORDING TO THE BRAZILIAN ASSOCIATION FOR AWARENESS OF THE DANGERS OF ELECTRICITY (ABRACOPEL), FROM 2015 TO 2020, OF THE 19,772 DEATHS CAUSED BY BURNS, 46.1% WERE DUE TO INJURIES CAUSED BY ELECTRICAL ACCIDENTS. ESTIMATED EFFECTS OF ELECTRIC SHOCK
9. DYNAMIC SHOCK ATMOSPHERIC DISCHARGE IN THIS TYPE OF SHOCK, THE PERSON COMES INTO DIRECT CONTACT WITH THE ENERGIZED SOURCE AND IS “SHOCK-PRONE” WHILE THE NETWORK IS SUPPLYING ENERGY OR WHILE THEY ARE IN CONTACT WITH THE ENERGY SOURCE. IT CAN CAUSE ANYTHING FROM MINOR INJURIES TO DEATH. THIS IS THE SHOCK CAUSED BY LIGHTNING THAT CAN DIRECTLY HIT THE PERSON OR PLACES CLOSE TO THEM. IN MOST CASES IT CAUSES BURNS AND DEATH. THERE ARE THREE TYPES OF ELECTRIC SHOCK STATIC SHOCK CAUSED BY AN ELECTRIC CURRENT THAT REMAINS ON CERTAIN SURFACES, RESULTING FROM FRICTION OR, FOR EXAMPLE, WHEN TWO INDIVIDUALS WITH DIFFERENT STATIC CHARGES SHAKE HANDS. BECAUSE IT IS SHORT-LIVED, THIS TYPE OF SHOCK USUALLY DOES NOT POSE ANY RISKS, EXCEPT WHEN THE ACCUMULATED CHARGE IS SIGNIFICANT ENOUGH TO CAUSE SPARKS.
10. LOW-VOLTAGE SHOCKS USUALLY CAUSE SUPERFICIAL INJURIES, WHILE PROLONGED EXPOSURE TO ELECTRIC CURRENT CAUSES DEEP BURNS. DEPENDING ON THE SEVERITY OF THE ACCIDENT, IN ADDITION TO BURNS, CARDIAC ARRHYTHMIA, TINGLING SENSATION, HEADACHES, CONVULSIONS AND LOSS OF CONSCIOUSNESS MAY OCCUR. IN MORE SERIOUS CASES, COMA, HEART ATTACK AND RESPIRATORY ARREST ARE AMONG THE COMPLICATIONS. WHAT HAPPENS WHEN SOMEONE GETS AN ELECTRIC SHOCK?
11. ABOUT HALF OF ALL ELECTRICAL SHOCK INJURIES OCCUR IN THE WORKPLACE. THEREFORE, PROFESSIONALS WHO PERFORM HIGH-RISK TASKS MUST ALWAYS WEAR PERSONAL PROTECTIVE EQUIPMENT (PPE). WHEN CARRYING OUT THE WELDING SERVICE, YOU SHOULD NOT: USE THE WELDING MACHINE NEAR WATER; DAMAGED CABLE; DAMAGED GROUNDING CABLE. FURTHERMORE, IT IS IMPORTANT TO CONSTANTLY REVIEW ELECTRICAL INSTALLATIONS AND EQUIPMENT TO AVOID ACCIDENTS. AVOID ACCIDENTS
12. ELECTRICAL PROTECTION DEVICES ARE DESIGNED TO INCREASE THE SAFETY OF ELECTRICAL INSTALLATIONS BY PREVENTING ELECTRIC SHOCKS, OVERHEATING OR CURRENT OR VOLTAGE SURGES. ACCORDING TO BRAZILIAN TECHNICAL STANDARD NBR 5410, WHICH DEALS WITH LOW-VOLTAGE ELECTRICAL INSTALLATIONS (UP TO 1000V), THESE DEVICES ARE MANDATORY IN AN INSTALLATION. THE THREE MAIN ONES ARE: CIRCUIT BREAKER, DPS AND IDR. UNDERSTAND THE DIFFERENCE AND HOW EACH ONE WORKS: ELECTRICAL PROTECTION
13. DIJUNTOR It is a device designed to disarm the circuit in which it is installed when it detects atypical heat indicating excess current. In this way, it prevents overloads and short circuits in an electrical installation. Circuit breakers can be: thermal, magnetic and thermomagnetic, single-pole, two-phase or three-phase and categorized according to the breaking curve, which can be curve B (e.g. showers, electric heaters, general-use sockets), curve C (air conditioning, lighting circuits and command and control systems) or curve D (large motors and large transformers). THE THREE MAIN ONES ARE: CIRCUIT BREAKER, DPS AND IDR, UNDERSTAND THE DIFFERENCE AND HOW EACH OF THEM WORKS: DPS (SURGE PROTECTION DEVICE) Its function is to protect installations against overvoltages caused by atmospheric phenomena. Working as a lightning rod, the DPS identifies extremely high voltages (surges) caused by lightning in the network and quickly diverts them to ground. The device is essential in installations and is mainly aimed at protecting electronic devices, preventing burns. The IDR has the function of protecting people and animals from being hit by current leaks (electric shocks). When the current leak exceeds 30mA, the IDR automatically turns off the circuit. According to the ABNT NBR 5410 standard, the use of IDR is mandatory in wettable areas (bathrooms, kitchens, service areas, garages) and in circuits that supply sockets in areas outside the building. The use of these devices is essential for a safe electrical installation and, therefore, also guarantees the safety of the environments and those who frequent them. IDR (DIFFERENTIAL SWITCHES)
14. WHEN ELECTRICAL CABLES ARE EXPOSED, THERE IS A SERIOUS RISK OF ELECTRIC SHOCK TO PEOPLE PASSING THROUGH THE AREA. DIRECT OR INDIRECT CONTACT WITH LIVE CABLES CAN LEAD TO SERIOUS INJURIES AND EVEN DEATH. THESE ACCIDENTS CAN OCCUR WHEN PEOPLE TRIP OVER CABLES OR WHEN THERE IS POOR INSULATION IN AREAS WHERE THERE IS MOISTURE. EXPOSED ELECTRICAL CABLES SIGNIFICANTLY INCREASE THE RISK OF FIRE AND SHORT CIRCUITS. EXPOSED WIRES AND CABLES ALLOW FLAMMABLE OBJECTS, SUCH AS PAPER, FABRICS AND COMBUSTIBLE MATERIALS, TO COME INTO CONTACT WITH LIVE PARTS, WHICH EMIT SPARKS AND EXCESSIVE HEAT. WELDING CABLES
15. IMPORTANCE OF WELL-STRUCTURED CABLING WITHOUT A DOUBT, WELL-STRUCTURED CABLING PLAYS A FUNDAMENTAL ROLE WITHIN COMPANIES. NOT ONLY TO AVOID PROBLEMS, BUT ALSO TO PROVIDE BENEFITS SUCH AS: RELIABILITY WELL-STRUCTURED CABLING PROVIDES A RELIABLE, HIGH-QUALITY INFRASTRUCTURE FOR TRANSMITTING DATA, VOICE, AND MORE. ORGANIZATION WELL-STRUCTURED CABLING MAKES IT EASIER TO MANAGE AND ORGANIZE CABLES. FLEXIBILITY AND SCALABILITY A WELL-DESIGNED CABLING STRUCTURE PROVIDES FLEXIBILITY AND SCALABILITY TO MEET THE EVER-EVOLVING NEEDS OF BUSINESSES. LONGEVITY WELL-STRUCTURED CABLING IS A LONG-TERM INVESTMENT.
16. IONIZING RADIATION IS RADIATION THAT HAS ENOUGH ENERGY TO REMOVE ELECTRONS FROM ATOMS, THUS CREATING IONS (INCA, 2021). NATURAL SOURCES OF IONIZING RADIATION ARE COSMIC RAYS AND RADIONUCLIDES FROM THE EARTH'S CRUST, FOUND IN PLACES SUCH AS SOIL, ROCKS, BUILDING MATERIALS, DRINKING WATER AND THE HUMAN BODY ITSELF. REGARDING EXPOSURE TO RADIATION FROM NATURAL SOURCES, RADON DESERVES SPECIAL MENTION. IT IS A NATURAL GAS, ODORLESS, COLORLESS, AND TASTELESS, WHICH TENDS TO BE CONCENTRATED IN CLOSED ENVIRONMENTS SUCH AS UNDERGROUND MINES, HOMES, OR WORKPLACES (INCA 2021, 2012). ONCE INHALED, RADON IS DEPOSITED IN THE RESPIRATORY TRACT AND IS ASSOCIATED WITH LUNG CANCER, BEING THE SECOND LEADING CAUSE OF LUNG CANCER AFTER SMOKING (WHO, 2016). ONE WAY TO PROTECT YOURSELF IS TO MAINTAIN WELL-VENTILATED ENVIRONMENTS, AVOIDING THE CONCENTRATION OF THIS GAS. IONIZING RADIATION NON-NATURAL, OR MAN-MADE, SOURCES OF IONIZING RADIATION ARE COMMONLY ENCOUNTERED IN HEALTH CARE (X-RAYS, COMPUTED TOMOGRAPHY, AND RADIATION THERAPY) AND POWER GENERATION (NUCLEAR POWER PLANTS).
17. THE RISK OF CANCER RESULTING FROM THIS EXPOSURE DEPENDS ON THE DOSE, THE DURATION OF EXPOSURE, THE AGE AT WHICH THE EXPOSURE OCCURRED AND OTHER FACTORS SUCH AS THE SENSITIVITY OF THE TISSUES TO THE CARCINOGENIC EFFECTS OF RADIATION. FORM OF EXPOSURE AT WORK INDIVIDUALS WORKING IN THE NUCLEAR INDUSTRY OR AROUND EQUIPMENT THAT EMITS RADIATION (MEDICAL INSTITUTIONS OR LABORATORIES); WORKERS IN UNDERGROUND HEMATITE MINES, DUE TO EXPOSURE TO RADON. ENVIRONMENTAL WE ARE ALL EXPOSED TO VARYING INTENSITIES OF RADIATION, INCLUDING THOSE FROM NATURAL AND MAN-MADE SOURCES.
18. ACUTE EFFECTS NAUSEA, WEAKNESS, HAIR LOSS, SKIN BURNS, OR DECREASED ORGAN FUNCTION. PATIENTS TREATED WITH RADIATION OFTEN EXPERIENCE ACUTE EFFECTS DUE TO HIGH-DOSE EXPOSURE. CHRONIC EFFECTS RADIATION CAN CAUSE CHANGES IN DNA. CANCER IS ALSO CONSIDERED AN EFFECT OF RADIATION EXPOSURE. MAIN HEALTH EFFECTS
19. THE STUDY ON THE RISKS OF EXPOSURE HAVING ALREADY BEEN OBSERVED, THE RESEARCH CENTERS REACHED THE FOLLOWING CONCLUSION, AS SHOWN IN THE TABLE BELOW: CONTROL MEASURES IT IS RECOMMENDED THAT ACTIVITIES TO BE CARRIED OUT IN WORK ENVIRONMENTS BE PROPERLY PLANNED IN ORDER TO REDUCE INDIVIDUAL DOSES, THE NUMBER OF PEOPLE EXPOSED AND THE LIKELIHOOD OF ACCIDENTAL EXPOSURE. PERSONAL AND COLLECTIVE PROTECTIVE EQUIPMENT (EPC AND PPE) MUST BE USED BY ALL WORKERS.
20. IN THE COURSE OF INDUSTRIALIZATION, METAL ALLOYS HAVE ALSO EVOLVED AND TODAY HAVE A LARGE NUMBER OF ALLOYS DIFFERENTIATED BY SPECIFICATIONS. AS A RESULT, THE TYPES OF WELDING TO SUIT THE DIFFERENT TYPES OF METAL ALLOYS HAVE ALSO EVOLVED, TODAY WE HAVE: FIXED WELDING FIXED WELDING IS THE SIMPLEST AND MOST WELL-KNOWN TYPE. THE WELDING MACHINE ELECTRODE IS COVERED BY A METAL COATING THAT JOINS AND FORMS A GAS THAT PROTECTS THE WELDER AGAINST THE HEAT! ANOTHER ADVANTAGE OF THIS TYPE OF WELDING IS THAT IT CAN BE DONE ON HORIZONTAL AND VERTICAL SURFACES. RISKS IN WELDING WITH SPECIAL PROCESSES (SUBMERGED ARC, MIG, MAG TIG) SUNDAY ME IDEAL FOR ENCLOSED SPACES. MIG WELDING IS USUALLY USED IN CLOSED SPACES, WITHOUT DRAFTS. THIS TYPE OF WELDING CAN BE APPLIED TO MATERIALS SUCH AS STAINLESS STEEL, CARBON STEEL AND ALUMINUM. IT IS ALSO GREAT FOR WELDING IN VARIOUS POSITIONS! TIG WELDING TIG WELDING USES TUNGSTEN GAS TO JOIN DIFFERENT TYPES OF METAL. HOWEVER, IT IS MORE PROFESSIONAL AND NEEDS TO BE DONE BY SOMEONE WITH A LOT OF SKILL AND EXPERIENCE.
21. METALLIC FUMES ARE VERY FINE SOLID PARTICLES OF METAL OXIDES FORMED DURING WELDING, WHICH CAN CAUSE HARM TO HEALTH, DEPENDING ON THE IMPURITIES, CONCENTRATION AND INTENSITY OF THE FUMES/GASES. THE FOLLOWING METAL FUMES CAN BE FOUND IN WELDING FUMES: ARSENIC, CADMIUM, IRON, COBALT, CHROMIUM, NICKEL, LEAD, MANGANESE AND ZINC, AMONG OTHER METALS AND COMBINATIONS. THEREFORE, THE RESPIRATORY RISKS OF INHALING METALLIC FUMES MUST BE MITIGATED TO AVOID OCCUPATIONAL PROBLEMS RELATED TO THIS CONTINUOUS EXPOSURE. ACCORDING TO FUNDACENTRO'S RESPIRATORY PROTECTION PROGRAM (PPR), WELDING IS: Welding is a process for joining materials, usually metals, by fusion. In civil construction, shipbuilding, automotive, etc., the use of MIG/MAG, Flux core, TIG, MMA and laser welding processes is common. METAL GASES AND FUMES During these processes, respirators are subject to additional risks such as excessive heat, the presence of sparks/metal splashes, electromagnetic compatibility (EMC) and UV radiation, requiring respirators to have high resistance/protection against such risks, in addition to the basic requirements. According to Regulatory Standard NR-09, Assessment and Control of Occupational Exposure to Physical Agents, of the Ministry of Labor, in its item 9.1.5.2., chemical agents are considered “substances, compounds or products that can penetrate the body through the respiratory tract, in the form of dust, smoke, mist, fog, gases or vapors, or that, due to the nature of the exposure activity, may have contact or be absorbed by the body through the skin or by ingestion”.
22. HOW METAL FUMES ARE FORMED WELDING REAGENTS BURN AT HIGH TEMPERATURES, PRODUCING A MIST OF METALLIC FUMES THAT ARE EXTREMELY TOXIC AND HARMFUL TO THE RESPIRATORY TRACT. FURTHERMORE, WHEN THIS VAPORIZED MATERIAL COOLS, IT CAN COMBINE WITH OXYGEN IN THE ATMOSPHERE, PRODUCING DUST THAT IS ALSO TOXIC AND HARMFUL. THE SMALLER THE PARTICLES, THE HIGHER THE TOXIC LEVELS OF THE DUST. TO MAKE THE SITUATION EVEN WORSE, IN SOME SITUATIONS METALLIC FUMES CAN COMBINE WITH WELDING GASES, GENERATING OZONE (O3) AND CARBON DIOXIDE (CO2). IF THE ENVIRONMENT IS POORLY VENTILATED, CARBON MONOXIDE (CO) MAY STILL BE FORMED DUE TO THE BURNING OF CO2 INSTEAD OF O2.
23. HELMET AND GLASSES EPI E EPC SIDING SCRAPER APRON GLOVE WE CLASSIFY PROTECTIVE EQUIPMENT AS: PERSONAL PROTECTIVE EQUIPMENT-PPE: ANY DEVICE OR PRODUCT, FOR INDIVIDUAL USE BY THE WORKER, INTENDED TO PROTECT AGAINST RISKS THAT MAY THREATEN SAFETY AND HEALTH AT WORK”. COLLECTIVE PROTECTION EQUIPMENT-EPC: EQUIPMENT THAT MUST BE PROVIDED BY THE COMPANY WITH THE AIM OF PROTECTING WORKERS FROM RISKS POSED BY THE WORK ENVIRONMENT, COLLECTIVELY. PORTABLE FIRE EXTINGUISHERS, EYE WASH STATIONS, EXHAUST FANS, FIRST AID KITS, FENCES, ETC.
24. RISK IN GOUGING OPERATION GOUGING OR GROOVE OPENING IS ONE OF THE VARIATIONS OF OPERATIONS POSSIBLE WITH OXYFUEL CUTTING EQUIPMENT. IT CONSISTS OF USING A CUTTING NOZZLE CONSTRUCTED WITH AN ANGULAR GEOMETRY TO ALLOW THE APPLICATION OF A CUTTING JET TANGENTIALLY TO THE SURFACE OF THE SHEET OR WELD BEAD. THE CUTTING JET OUTLET OF THE NOZZLE IS ALSO MODIFIED TO PRODUCE A SHORT, WIDE OXYGEN JET. THE PURPOSE OF GOUGING IS SUMMARIZED IN TWO OPERATIONS: TYPICALLY, NOZZLES HAVE A HARD METAL INSERT IN THEIR LOWER PART THAT COMES INTO CONTACT WITH THE SHEET METAL TO RESIST FRICTION AND ENSURE THE CORRECT OPERATING DISTANCE.
25. A VARIATION OF GOUGING NOZZLES ARE RIVET EXTRACTOR NOZZLES THAT HAVE A SMALLER CUTTING JET AND ARE USED TO QUICKLY REMOVE RIVET AND SCREW HEADS DURING DISASSEMBLY AND MAINTENANCE OF ASSEMBLED METAL STRUCTURES. THE NOZZLES CAN WORK WITH OXYGEN AND ACETYLENE OR OXYGEN AND LPG. OPENING GROOVES IN PLATES FOR SUBSEQUENT WELDING. THE SIZE OF THE GROOVE WILL DEPEND ON THE NOZZLE NUMBERING SPECIFICATION. REMOVAL OF WELD BEADS OR PART THEREOF AFTER DETECTION OF WELDING DEFECTS.