Basic Welding Mid-term Exam

Burns are indeed some of the most common and painful injuries in a welding shop. This is because welding involves working with high temperatures, sparks, and molten metal, which can easily cause burns if proper safety precautions are not taken. Welders are at risk of getting burned from direct contact with hot metal, from sparks and slag flying off the welding process, or from exposure to ultraviolet radiation. Therefore, it is important for welders to wear protective clothing, such as flame-resistant gloves and clothing, to minimize the risk of burns.

The statement "Gas cylinder must be chained or secured at all times" is true. This is important for safety reasons as unsecured gas cylinders can pose a significant risk. Chaining or securing the gas cylinder prevents it from falling or tipping over, which could lead to gas leaks, explosions, or other accidents. By keeping the gas cylinder properly secured, the chances of accidents or injuries are minimized, ensuring the safety of individuals and the surrounding environment.

Acetylene cylinders should never be operated while lying on their side because when they are in this position, there is a risk of acetone being drawn into the valve, regulator, and hose. This can lead to potential hazards and compromise the safety of the operation. Therefore, it is important to always keep acetylene cylinders in an upright position to prevent any potential accidents or damage.

Long hair, loose fitting clothes, and ties can be dangerous when working with rotating equipment because they can get caught in the machinery, leading to serious injuries or even death. The rotating parts can easily entangle and pull in loose clothing, causing the person to be pulled into the equipment. Ties can also get caught in the machinery, posing a similar risk. Therefore, it is important to avoid wearing long hair, loose fitting clothes, and ties when working around rotating equipment to ensure personal safety.

When working with electrodes, it is important to avoid touching them to any metal surface other than the workpiece. This is because those surfaces can become electrically live, meaning they can carry an electrical current. Touching the electrode to such surfaces can result in electric shock or other hazards. Therefore, it is crucial to only make contact between the electrode and the intended workpiece to ensure safety during electrical work.

Ventilation should be placed as close to the fume source as practical in order to effectively remove the fumes and gases generated during welding. This helps to minimize the exposure of the welder and others in the vicinity to potentially harmful fumes and ensures a safer working environment. By placing the ventilation close to the fume source, the fumes can be captured and removed more efficiently, reducing the risk of respiratory issues and other health hazards associated with welding fumes.

Skin contact with liquid oxygen can cause frostbite because liquid oxygen is extremely cold, with a boiling point of -183 degrees Celsius. When it comes into contact with the skin, it rapidly evaporates and absorbs heat from the surrounding tissues, causing severe cold burns and frostbite. Therefore, it is important to handle liquid oxygen with caution and avoid direct contact with the skin to prevent frostbite injuries.

Oxygen cylinders should never be stored with flammable gases such as acetylene cylinders because oxygen supports combustion and can accelerate the burning process. Mixing oxygen with flammable gases increases the risk of fire or explosion. Therefore, it is crucial to store oxygen cylinders separately from flammable gases to ensure safety.

A striker is the only acceptable method for lighting oxyfuel torches because it provides a controlled spark that can ignite the fuel mixture in a safe and efficient manner. Matches and a cigarette lighter may not provide a consistent spark, and a welding arc is not suitable for lighting oxyfuel torches as it produces a high-intensity heat that can be dangerous. Therefore, a striker is the preferred tool for safely igniting an oxyfuel torch.

When not in use, an electrode holder GTAW torch or MIG gun should not be placed in contact with a grounded metal surface because it can cause a short circuit or electrical shock. Grounded metal surfaces can conduct electricity, and if the electrode holder or MIG gun is in contact with them, it can create a path for the electrical current to flow, leading to potential hazards. Therefore, it is important to keep these tools away from grounded metal surfaces when they are not being used to ensure safety.

Fuel gas fittings are equipped with left-hand threads because it is a safety measure. Left-hand threads are designed to prevent accidental loosening of the fittings due to the rotation of the connected pipes or hoses. This is especially important for fuel gas fittings, as any leakage can lead to hazardous situations such as gas leaks or fires. The use of left-hand threads ensures that the fittings remain securely tightened, reducing the risk of accidents and ensuring the safe operation of fuel gas systems.

The potential hazards related to arc welding include radiation, fumes, and toxic gases. Radiation can cause burns and eye damage, while fumes and toxic gases can lead to respiratory problems and other health issues. Therefore, all of the options mentioned in the question are correct as they all pose risks during arc welding.

When using a fire extinguisher to extinguish a fire, it should be pointed at the base of the fire because this is where the fuel source is located. By directing the extinguisher at the base, it helps to cut off the supply of fuel and effectively put out the fire. Pointing at the top of the flames or holding it within 6 inches of the flame may not be as effective as it does not target the source of the fire. Moving the extinguisher up and down to cool the flames may help in certain situations, but it is not the most effective method for extinguishing the fire.

Safety glasses are essential when entering a welding shop to protect the eyes from sparks, debris, and harmful UV radiation emitted during the welding process. While gloves, a welding helmet, and welding leathers are also important safety equipment, they specifically protect the hands, head, and body from burns, sparks, and heat, respectively. However, safety glasses are crucial for eye protection, as welding without them can lead to serious eye injuries or damage.

OSHA stands for the Occupational Safety and Health Administration, which is a federal organization created to ensure safe and sanitary working conditions for employees. They establish and enforce standards, provide training and education, and conduct inspections to promote workplace safety and protect workers from hazards.

Operating arc welding equipment while standing on wet or damp floors can be extremely dangerous. Water is a good conductor of electricity, and if the equipment comes into contact with the wet or damp floors, it can cause electric shock or electrocution to the operator. This can result in serious injury or even death. Therefore, it is important to always ensure a dry and safe working environment when operating arc welding equipment.

Keeping a butane or propane cigarette lighter in one's pocket around welding equipment is not safe. These lighters are highly flammable and can ignite easily when exposed to sparks or heat from welding equipment. Therefore, it is not recommended to keep them in close proximity to welding equipment to prevent accidents or fires.

Fuel gas hoses are usually colored red to indicate that they are used for fuel gas applications. The color-coding system helps to easily identify and differentiate between different types of hoses. Red is commonly associated with fuel gas, while other colors may be used for different purposes such as green for oxygen, blue for air, and yellow for flammable liquids. The use of color-coding ensures safety by preventing mix-ups and potential hazards in industrial settings where various gases and liquids are used.

Mechanized OFC refers to the process of burning off excess organic material on a track using specialized equipment. This process is commonly known as a track burner because it involves using high heat to rapidly burn off the vegetation on the track, allowing for smoother and safer operations. Therefore, the statement "Mechanized OFC is commonly referred to as a track burner" is true.

Safety glasses are always required when welding, regardless of whether the helmet is down or not. Welding generates intense heat, sparks, and UV radiation, which can cause eye injuries if proper eye protection is not worn. The helmet provides protection for the face and head, but safety glasses are necessary to protect the eyes from potential hazards. Therefore, the statement that safety glasses are not required when welding with the helmet down is false.

Acetylene can indeed be used with an oxyfuel cutting tip. Oxyfuel cutting is a process that involves using a mixture of fuel gas and oxygen to create a high-temperature flame for cutting or welding. Acetylene is a commonly used fuel gas in oxyfuel cutting due to its high flame temperature and ability to produce a concentrated and stable flame. Therefore, the statement that acetylene can be used with an oxyfuel cutting tip is correct.

Acetylene has a maximum safe working pressure of 15 psi. This is because acetylene is a highly flammable gas and can become unstable at high pressures, increasing the risk of explosion. Therefore, it is important to ensure that the pressure is kept below this limit to maintain safety while working with acetylene.

The given correct answer states that vaporized metals such as zinc, cadmium, lead, chromium, and beryllium are hazardous. This means that when these metals are converted into vapor form, they pose a danger or risk to health, safety, or the environment. It implies that exposure to these vaporized metals can have harmful effects and precautions should be taken to avoid any potential hazards associated with them.

Oil should never be used on gas cylinders, regulators, connections, and hoses because oil can cause damage to the rubber seals and O-rings, leading to leaks and potential hazards. Oil can also react with certain gases and create a fire or explosion risk. It is important to use appropriate lubricants and follow manufacturer's recommendations to ensure the safety and proper functioning of gas equipment.

A Hot Work Permit authorizes the performance of work potentially posing a fire hazard. This means that before conducting any work that involves heat, sparks, or open flames, a permit must be obtained to ensure that proper safety precautions are in place to prevent fires. The permit serves as a way to regulate and control potentially dangerous activities, ensuring that they are carried out safely and minimizing the risk of fire incidents.

Operating welding equipment beyond its rated capacity is not acceptable in order to maintain production. This is because operating equipment beyond its rated capacity can lead to various issues such as equipment damage, decreased efficiency, increased risk of accidents, and poor quality of the welding work. It is important to operate equipment within its specified limits to ensure safety, maintain productivity, and produce high-quality welds.

Acetylene is a highly flammable gas that can be unstable and explosive at high pressures. Therefore, it is important to ensure that the working pressure for acetylene is within a safe range to prevent accidents. The maximum safe working pressure for acetylene is 15 psi. This pressure limit helps to minimize the risk of ignition or explosion while handling and using acetylene gas.

Flash burn is a burn to the eye caused by exposure to ultraviolet light from the welding arc. When a person's eyes are exposed to the intense ultraviolet light emitted during welding, it can cause a painful burn on the surface of the eye. This can result in symptoms such as redness, swelling, tearing, and sensitivity to light. Flash burns can be prevented by wearing appropriate eye protection, such as welding goggles or a welding helmet with a proper shade lens, which can filter out the harmful ultraviolet light.

Regulators are the devices used to control the pressure on an oxyfuel cutting torch set. They are responsible for maintaining a consistent and accurate flow of oxygen and fuel gases to achieve the desired cutting or welding results. Valves control the flow of gases, handles provide grip and control, and wing-pressure adjusting screws are not typically used in the context of oxyfuel cutting torch sets. Therefore, regulators are the correct answer for this question.

Concrete should never be cut or welded directly against because it can release harmful fumes and dust particles. These fumes and particles can be hazardous to health and may cause respiratory issues. Additionally, cutting or welding against concrete can weaken its structure and cause damage. It is important to take necessary precautions and use appropriate tools and techniques when working with concrete to ensure safety and maintain the integrity of the material.

Class C fire extinguishers are specifically designed to extinguish fires caused by electrical equipment. These fires involve energized electrical equipment such as appliances, wiring, circuit breakers, and outlets. Class C extinguishers contain non-conductive extinguishing agents that do not conduct electricity, allowing them to safely extinguish the fire without the risk of electric shock to the user. Therefore, class C fire extinguishers are the appropriate choice for electrical fires.

Fuel gas fittings typically have left-hand threads and are color-coded with red. The left-hand thread is used to prevent accidental cross-connection with other types of fittings, ensuring that the fuel gas is properly connected. The color red is commonly associated with fuel gas fittings to easily distinguish them from other types of fittings and indicate the presence of potentially hazardous materials.

The term for the width of the cut produced by any cutting process is called "kerf".

All three fuel gases, MAPP, propane, and acetylene, can be used to cut low-carbon steel. Each gas has its own advantages and disadvantages, but all are capable of providing the heat and energy required to melt and cut through the steel. MAPP gas burns at a higher temperature than propane, making it more suitable for thicker steel, while acetylene has a high heat output and is commonly used for cutting and welding. Therefore, all three gases can be used effectively for cutting low-carbon steel.

Oxyacetylene torches can cut carbon steels because the high temperature flame produced by the torch can melt and vaporize the steel, allowing it to be cut easily. Carbon steels have a lower melting point compared to stainless steel, aluminum, and copper-nickel alloys, making them more suitable for cutting with an oxyacetylene torch.

The oxyfuel cutting process uses oxygen and flammable gases. These gases are necessary to create a high-temperature flame that can melt and cut through metal. In addition to oxygen, commonly used flammable gases in oxyfuel cutting include acetylene, propane, and natural gas. These gases are highly combustible and provide the heat source required for the cutting process.

A burn that causes the skin to blister is referred to as a second degree burn. This type of burn affects both the epidermis (outer layer of the skin) and the dermis (underlying layer of the skin). It is characterized by redness, pain, swelling, and the formation of blisters. Unlike a first degree burn, which only affects the epidermis and causes redness and mild pain, a second degree burn is more severe and requires medical attention for proper treatment and care. A third degree burn involves damage to deeper layers of the skin, while a fourth degree burn extends beyond the skin and affects underlying tissues and organs.

The correct lens shade number for welding depends on the amount of welding current being used. The lens shade number indicates the level of darkness of the lens, which protects the eyes from the bright light emitted during welding. Different welding processes and current levels produce varying levels of brightness, so the appropriate lens shade number should be selected to provide adequate protection for the specific welding conditions.

The correct answer is "is large enough that a person can enter and perform tasks." This means that a confined space is a space that is big enough for a person to enter and carry out their work. It does not necessarily have a flammable atmosphere, an unrestricted means of entry or exit for employees, or be designed for continuous employee occupancy. The defining characteristic of a confined space is its size and suitability for work tasks.

When oxyfuel cutting, it is necessary to wear shaded lenses. This is because oxyfuel cutting uses a flame, which emits intense ultraviolet (UV) and infrared (IR) radiation. These radiations can be harmful to the eyes and can cause damage such as arc eye or welder's flash. Shaded lenses provide protection by reducing the amount of UV and IR radiation that reaches the eyes, ensuring the safety of the person performing the oxyfuel cutting operation.

Areas that have less than 10,000 cubic feet per welder, or that have ceilings less than 16 feet high, require forced ventilation. The given answer of 10,000 is the threshold for determining when forced ventilation is necessary. If the area has less than 10,000 cubic feet per welder or a ceiling height of less than 16 feet, it does not have sufficient ventilation and therefore requires forced ventilation to ensure the safety and well-being of the welders.

When cutting with acetylene, the oxygen working pressure needs to be greater than the acetylene working pressure. This is because the oxygen is used to support and enhance the combustion of acetylene, allowing for a hotter and more efficient flame for cutting. By increasing the oxygen pressure, the flame temperature can be increased, resulting in faster and more effective cutting.

Cotton is the preferred type of clothing to be worn when using an OFC torch because it is a natural fiber that is less likely to catch fire or melt compared to other materials. Cotton is also breathable and comfortable, making it suitable for long periods of use. It is important to wear clothing that provides protection and minimizes the risk of burns or injuries when working with a torch.

During flame cutting, the preheat flames should be neutral. This means that the flame should have an equal balance of oxygen and fuel, creating a neutral atmosphere. A neutral flame ensures that the metal being cut does not oxidize or become carburized, which could negatively affect the quality of the cut. By maintaining a neutral flame, the heat is evenly distributed and the cutting process is more efficient and precise.

When an excessive amount of preheat is used during an oxyfuel cut, it can cause the top edge of the cut to melt or be completely removed. This occurs because the intense heat softens and melts the material, causing it to lose its structural integrity and potentially be removed by the cutting stream.

Federal regulation requires that hazardous information about a product be provided to all users of that product. The form used to provide this information is called a Material Safety Data Sheet (MSDS). The MSDS contains detailed information about the potential hazards of a product, including its physical and chemical properties, safe handling and storage procedures, emergency response measures, and regulatory information. It is important for users to have access to this information to ensure their safety and to comply with regulatory requirements. The other options, Information Form (IF), Hazardous Information Sheet (HIS), and Occupational Safety and Hazard Form (OSHF), are not commonly used terms and do not accurately describe the required form.

A carburizing flame in oxyacetylene welding has an excess of fuel. This means that there is more acetylene in the mixture compared to the amount of oxygen. The excess fuel creates a reducing atmosphere, which is ideal for certain types of welding and brazing applications. In a carburizing flame, the excess fuel helps to protect the metal from oxidation and allows for the introduction of carbon into the weld, enhancing its strength and hardness.

A fully charged oxygen cylinder does not contain approximately 225 psi at 70 degrees F. The pressure inside a fully charged oxygen cylinder can vary depending on the specific type and size of the cylinder, but it is typically much higher than 225 psi. Additionally, the pressure inside the cylinder can change with temperature, so it may not remain constant at 70 degrees F. Therefore, the statement is false.

ANSI Z49.1 does not allow oxygen to be used as a substitute for compressed air when necessary. Oxygen should not be used as a substitute for compressed air because it can increase the risk of fire and explosion. Oxygen supports combustion, and using it in place of compressed air can lead to hazardous situations. Therefore, the statement is false.

The statement is true because oxy-fuel cutting does not produce a significant amount of ultraviolet light. Shaded lenses are typically used to protect the eyes from intense ultraviolet radiation, which is commonly emitted during processes like welding. However, since oxy-fuel cutting does not generate high levels of ultraviolet light, there is no need to use shaded lenses for eye protection during this specific process.