safety in welding & gas

8/8/2019 Safety in Welding & Gas

1/24

SAFETY IN WELDING & GAS

CUTTING


2/24

Health Hazards

y Gases and Fumesy Welding Smoke is a mixture of very fine particles

called fumes and gasesy Welding Smoke contains fumes and gases

includingChromium, nickel, arsenic, asbestos, manganese,silica, beryllium, cadmium, nitrogen oxides,phosgene,acrolein, fluorine compounds, carbon monoxide,cobalt, copper, lead, ozone, selenium, and zinc


3/24

Health Hazards G ases & Fum es

Generally, gases and fumes come fromBase material & filler materialCoatings & paintsShielding gases & chemical reactionsProcess & consumables usedContaminants in the air


4/24

Health Hazards

y Exposure to welding smoke may haveShort-term effectsE ffects happen at or very soon after exposureLong-term effectsE ffects may happen after repeated overexposuresor an extended time after the exposure


5/24

S hort-ter m expos u res

Exposure to zinc, magnesium, copper and copperoxide can cause metal fume feverSymptoms of metal fume fever may occur 4 to

12 hours after exposureSymptoms include

Chills, thirst, fever, muscle ache, chest

soreness, coughing, wheezing, fatigue,nausea, and metallic taste in mouth


6/24


Welding smoke can irritate the eyes, nose,chest and respiratory tract Welding smoke can cause nausea, loss of appetite, vomiting, cramps, and slow digestion


7/24


Exposure to cadmium can be fatal in a short timeUltraviolet radiation can react with oxygen andnitrogen to form ozone and nitrogen oxides

These gases are deadly at high concentrations andcan also cause irritation of nose and throat and causeserious lung disease


8/24

L ong-ter m expos u res

Studies of welders, flame cutters, and burners haveshown that welders have an increasedrisk of lung cancer and possibly cancer of the larynx

and urinary tractRemember welding smoke can include cancercausing agents such as cadmium, nickel, beryllium,chromium, and arsenic


9/24

L ong-ter m expos u res

Welders may experience a variety of chronicrespiratory problems, includingBronchitis, asthma, pneumonia, emphysema,

pneumoconiosis, decreased lung capacity, silicosis,and siderosis


10/24

O ther Health Ri sks

H eat exposureH eat stress, heat stroke burns, eye injuries from hot slag, metal chips, sparks,and hot electrodes


11/24


V isible light, and ultraviolet and infrared radiationIntense light can cause damage to retinaInfrared radiation may damage the cornea and result

in cataracts

Invisible U V light can cause arc eye or welders flash

May include sandy or gritty eye, blurred vision,intense pain, tearing, burning and headache


12/24


Permanent eye damageSkin burnsSkin cancerNoiseCan result in stress, increased blood pressure, may contribute to heart disease, tiredness, nervousness,and irritability


13/24

M u sc u loskeletal I nj u r i es

Back injuries, shoulder pain, tendonitis, reducedmuscle strength, carpal tunnel syndrome, whitefinger, and knee joint diseases

Injuries may be caused by overhead work, vibrationand heavy lifting


14/24

E lectr i cal Hazards

E ven though welding generally uses low voltage,there is still a danger of electric shock Wet work areas, Cramped work spaces

Falls, fractures and other accidents can result fromelectrical exposureE ven small shock can cause brain damageDeath can occur from large shocks


15/24

Fi re and E xplos i on Hazards

Intense heat and sparks can cause fires or explosionsif in the vicinity of combustible or flammablematerials

Welding and cutting should only be performed inareas free of combustible materials such as trash, wood, paper, textiles, plastics, chemicals, andflammable dusts, liquids and

gases


16/24

Fi re and E xplos i on Hazards

Never weld or cut on containers that have held aflammable or combustible material unless thecontainer is thoroughly cleaned or filled with an inert

gas A fire inspection should be performed prior toleaving a work area and for at least 30 minutes afterthe operation is completed

Fire extinguishers should be nearby, of proper size,type and number for the hazards involved


17/24

T r i ps and F alls

y To prevent trips and fallskeep work areas clear of equipment, machines,cables, and hoses

Always properly maintain and use handrails Always use and maintain safety lines, harnesses andlanyards Always make sure that scaffolds are properly assembled and used


18/24

W eld i ng Hazards i n C onf i ned S pace

A work area with limited access, little or no airflow,not intended for continuous occupation

May also have dangerous atmospheres, hazardous configurations,

or other hazards All employees working in or around confined spacemust be trained


19/24


Never weld or cut in explosive, flammable,combustible or other dangerous environments Always use all necessary Personal Protective

Equipment (PP E) , including, harness and lanyard,respiratory protection, eye protection, etc.Never work in confined space without a trainedattendant


20/24


Always leave gas cylinders and welding powersources outside the confined spaceOnly take hoses or welding leads into confined space

Always removed hoses and/or leads when leavingconfined space for breaks, shift or crew changes, etc.


21/24


No worker should work in an area with less than19.5% or more than 23.5% oxygen contentNever ventilate with oxygen

Use continuous mechanical ventilation and properrespiratory protection All pipes, ducts, power lines, etc. that are notnecessary for the work should bedisconnected/locked out/tagged out


22/24

C o m pressed G as Hazards

Gas welding and cutting use a fuel gas and oxygen which are stored in high pressure cylindersMost fuel gases are explosive

Pure oxygen will increase the flammability of any combustible/flammable material


23/24

E ng i neer i ng C ontrols and W ork P ract i ces

y Substitute less hazardous materials for hazardousmaterials

y Use cadmium-free silver soldersy Use asbestos- free electrodes, gloves, and hot padsy Use ventilation to move away or dilute hazardsy Use work area barriers to protect others working in

the same general area


24/24

E ng i neer i ng C ontrols and W ork P ract i ces

y Welding booths should be painted with dull finishesso they dont reflect U V light

y Acoustic shields between the worker and noise

sources can reduce exposuresy Noisy machinery can be totally enclosed

safety in welding & gas

Documents