In 2018, one of the largest meat processing facilities in South Australia broke out in flames, causing millions of dollars in damages. Investigations determined that a worker welding an offal bin had accidentally started the fire, which spread rapidly across the premise after it went into a highly combustible wall.
Had the workers not evacuated in the time that they did, the result may have been much more catastrophic. Although the devastating blaze broke out on a Wednesday ripping its way through to Friday, this tragedy highlights only one of the dangers of welding.
Although the pipe welding process itself may not be complex, the potential dangers certainly are. Some of the risks to consider may include:
Given the number potential dangers in welding processes, there are several people who are responsible for health and safety duties in relation to pipe welding. Those who have a role in managing the risks of pipe welding processes include:
Staff members and those at the workplace where pipe welding is to be performed also have duties under the Work Health and Safety Act, such as the duty to take reasonable care for their own health and safety at the workplace. As shown, there are many moving parts to a safe and efficient work environment for welding. But before we explore further, lets discuss the basics of pipe welding.
Pipelines are viewed as the veins of modern infrastructures and can be used in the transportation of oil, water, gas, and other important amenities. Therefore, pipe welding is sometimes necessary to perform repairs, construction, maintenance, and even replacements. However, it should only be conducted by certified personnel. The main aim of pipe welding is to ensure the entire system is secure and sealed. It is also important to note that varying grades of piping require varying welding processes.
The common types of pipe welding may include:
In arc welding, the welder must have an electrode and a welding gun. A metal wire fed to the gun is heated until it melts. The molten metal applied to the pipe’s connection points create the weld. Arc welding is suitable for heavy and thick metals such as cast iron.
Metal inert gas welding is a form of arc welding most suitable for aluminum, mild steel, and stainless steel. The process entails the use of wire fed going through a wire electrode in a welding handgun. The process does not require any mixing of the gases, making it the quickest form of welding.
This form of arc welding requires an expert welder. Its application is similar to MIG welding, the only difference being the use of a tungsten electrode instead of a wire electrode to produce the arc. It has a clean finish making the welded pipe look attractive and professional. This type of welding is the most suitable for various metals and alloys such as magnesium, aluminium, and copper alloys. However, it is worth noting that different types of metals require different tungsten electrodes.
This type of welding does not entail the creation of an electrical arc. It entirely involves the use of oxygen and acetylene to produce a super-hot flame. The flame can melt steel and create a strong weld. The filler rod is occasionally added to the welding area.
As opposed to other processes where welding machines are used, oxyacetylene welding involves the use of a torch attached to acetylene and oxygen bottles, a regulator, and gas hoses. It is suitable for soft metals such as bronze and copper.
Studies show that full-time welding may be associated with serious health issues such as bronchitis, airway irritation, effects on lung functions, and other changes. The airborne hazards pipe welders may encounter primarily fall into one of two categories:
Electric arc and laser welding emit ultraviolet, visible light and infra-red radiation. Gas welding emits visible light and infra-red radiation. Certain types of UV radiation can produce an injury to the surface and mucous membrane (conjunctiva) of the eye called "arc eye," "welders' eye" or "arc flash." These names are common names for "conjunctivitis", an inflammation of the mucous membrane of the front of the eye.
The amount of time required to cause effects to the eye also depends on several factors such as the intensity of the radiation,
Welding arcs and flames emit intense visible, ultraviolet, and infrared radiation which pose as potential skin hazards. UV radiation in a welding arc will burn unprotected skin. Just like UV radiation in sunlight, it could potentially lead to skin cancer.
To prevent injury or death by electricity, electrical equipment must be regularly inspected and tested by a competent person. Especially if it is used in an environment in which the normal use of the equipment exposes it to damaging operating conditions or reduce the life of the equipment. This could mean exposure to moisture, heat, vibration, mechanical damage, corrosive chemicals, or dust.
Electric shock or electrocution can occur through direct contact with the electrode, live parts, the work piece, or through contact with a device such as an unearthed cable or tool. This in turn increases the risk dramatically.
Electromagnetic fields close to a power source can also disrupt the operation of pacemakers, permanent defibrillators or other medical devices which could affect a person’s heart rate.
Under the Work Health and Safety Act regulations, an atmosphere is hazardous if the concentration of a flammable gas, vapour, mist or fume exceeds five per cent of the lower explosive limit for the gas, vapour, mist or fume.
Pipe welding generates heat, flames and sparks, which are all sources of ignition. This risk is especially high when pipe welding is necessary for repairs. When combined with fuel and oxygen, sources of ignition present a significant risk of fire and explosion, as presented in the disaster story earlier.
With the temperature of a welding arc ranging from 3,000 to 20,000 degrees Celsius, burns are one of the most common injuries in welding. Hazards can come from sparks and spatter flying off the welding arc, sparks and hot metal blowing off the cutting flame, and hot equipment. Additionally, arc rays can cause radiation burns.
Depending on the type of welding, compressed and liquefied gases can be used as fuel, a source of oxygen or as shielding gases. The associated hazards include fire, explosion, toxicity, asphyxiation, oxidisation and uncontrolled release of pressure. Gas leakage is a specific hazard that requires extra care as fuel gas leakage can often be detected by odour, but oxygen leaks are harder to detect.
Those responsible for duty of care must ensure that the noise exposure at work does not exceed the acceptable standard level. Exposure to high noise levels can cause permanent hearing loss. Equipment for performing welding can generate varying levels and frequencies of noise, therefore requires careful consideration when identifying these risks.
Lead is one of the many heavy metals that pose a risk when using welding fluxes. It has the potential to become an airborne contaminant when soldering and welding materials.
If you cut a piece of pipe that has been coated with paint that contains lead, it can also give off welding fumes containing lead oxide. Inhaling these fumes can cause lead poisoning, in which you become weak and develop anemia (a low red blood cell count).
Other potential health risks relating to pipe welding (or welding in general) can be associated with the confined spaces at a workplace. This may include risks associated with entering, working in, on or in the vicinity of a confined space. Another common risk is the lack of ventilation. In this case the heat, fumes and other airborne contaminants can be trapped in the work area posing health and safety risk to the worker.
A risk assessment is not mandatory for welding processes under the Work Health and Safety (WHS) Act Regulations. However, given the potential dangers it will be the best way to determine how to manage these risks.
The first step in the risk management process is recognising all the pipe welding hazards. This involves identifying elements and situations which could potentially cause harm to people.
The risk assessment may involve a simulation of a pipe welding project and anticipate the different types of risks, the precautions to prevent this, and the actions to take if someone is exposed.
Depending on the type of risk, a model Code of Practice has been developed to provide practical guidance for persons who have duties to manage risks to health and safety under the WHS Act and regulations applying in a jurisdiction. For more information visit Safe Work Australia.
Great question. Despite all this talk of all the dangers and risks of welding, the aim is always to eliminate the risk. So, if it’s at all possible, why not just eliminate the need to weld pipe?
You can minimise or eliminate the risk all together by substituting pipe welding with something that gives a lesser risk - press fit.
Press fit is an alternative method that ensures the safety of the user and surrounding workers. Our process at IBEX Australia involves the use of a stainless-steel press fit piping system made from either 304L or 316L stainless steel.
The beauty of this?
Note: Times include full joint preparation and completion: cutting, deburring, witness marking and pressing / welding of the joint. Times do not cover any joint finishing, i.e. pickling and pasting, non-destructive testing, etc. All press fit times have been timed by IBEX Australia.
All conventional welding times have been provided by a third party company and are for preparation and welding under professional workshop conditions.
With the press fit piping system being a clear and superior substitute to pipe welding, consider using press fit for your next project.
To speak to one of our experts about using stainless steel in your project, call us on 1300 85 45 20