Unit 3, Welding Safety And First Aid, Obj. 8-15

Keeping cables and hoses coiled free of kinks and properly stored when not in use is important for their longevity and functionality. Coiling them helps prevent tangling and damage, while storing them properly prevents them from being exposed to elements such as moisture or extreme temperatures. This ensures that the cables and hoses remain in good condition and can be used effectively when needed. Therefore, the statement "When not in use, keep cables and hoses coiled free of kinks and properly stored" is true.

Acetylene is a highly flammable gas, and it can easily ignite when exposed to open flames. Therefore, it is important to store acetylene cylinders safely away from any potential sources of ignition to prevent accidents or fires. This makes the statement "Because acetylene burns readily, acetylene cylinders should be kept safely away from open flames" true.

Welding cables carry high levels of electrical current, and draping them over a gas cylinder can cause damage to the cable insulation, leading to potential electrical shock or fire hazards. Striking an arc on a gas cylinder can cause sparks or heat that may ignite flammable gases or materials present in the vicinity, leading to explosions or fires. Therefore, it is crucial to never drape a welding cable over a gas cylinder and never strike an arc on a gas cylinder.

Dragging cables or hoses through dirt or oil can cause damage to the cables or hoses, leading to potential electrical or fluid leaks. Similarly, pulling on a cable to force it over an obstruction can strain or break the cable, resulting in potential electrical hazards or loss of connectivity. Therefore, it is important to avoid dragging cables or hoses through dirt or oil and to never force a cable over an obstruction.

Propane and MPS cylinders should be stored in clean, dry, well-ventilated locations free from other combustibles to minimize the risk of fire or explosion. Propane is a highly flammable gas, and storing it in a clean and dry environment helps prevent corrosion and leaks. Adequate ventilation is necessary to disperse any potential gas leaks and prevent the buildup of flammable vapors. Additionally, keeping these cylinders away from other combustible materials reduces the risk of accidental ignition. Therefore, it is important to store propane and MPS cylinders in a clean, dry, well-ventilated location free from other combustibles to ensure safety.

Acetylene cylinders should be stored in clean, dry, well-ventilated locations free from other combustibles because acetylene is a highly flammable gas that can easily ignite in the presence of heat, sparks, or flames. Storing acetylene cylinders in a clean and dry environment helps to prevent any moisture or contaminants from reacting with the gas and causing potential hazards. Adequate ventilation is necessary to disperse any leaked gas and minimize the risk of accumulation. Additionally, keeping acetylene cylinders away from other combustible materials reduces the chances of fire or explosion in case of a leak or accident.

Both propane and MPS cylinders should be used and stored in the upright position to ensure safety. Storing them upright prevents any leakage or accidental release of the gas. Additionally, using them in the upright position allows for better control and regulation of the flow of gas. Storing or using these cylinders in any other position can pose a risk of gas leakage, which can be hazardous and potentially lead to accidents or fires. Therefore, it is important to always follow the recommended guidelines and store and use propane and MPS cylinders in the upright position.

The statement is true because natural gas in cylinders, like any other fuel gas, can pose potential risks if mishandled. Precautions should be taken to ensure the safe handling, storage, and use of natural gas cylinders to prevent accidents, leaks, or explosions. This includes proper storage in well-ventilated areas, avoiding exposure to heat or flames, and using appropriate safety equipment such as gloves and goggles when handling the cylinders.

When moving cylinders, the correct method is to tilt them and roll them on their bottom edges. This means that the cylinders should be inclined at an angle and then moved by rotating them on their base. Rolling is the appropriate action for moving cylindrical objects as it allows for smooth and controlled movement without causing damage or instability. Bouncing, on the other hand, involves a sudden and uncontrolled motion that is not suitable for moving cylinders. Therefore, rolling is the correct answer.

Using welding cable covers is a recommended practice to ensure safety and protection. Welding cables carry high currents and are prone to damage from heat, sparks, and physical abrasion. By using cable covers, the cables are shielded from these potential hazards, reducing the risk of electrical shock, fire, and equipment damage. Cable covers also help in organizing and managing the cables, preventing tripping hazards and improving overall workspace safety. Therefore, the statement "Use welding cable covers" is true.

Acetylene cylinders should be protected against extreme temperature rises because acetylene is a highly flammable gas that can become unstable and explode if exposed to high temperatures. Therefore, it is crucial to store and handle acetylene cylinders in a controlled environment to prevent any potential accidents or hazards.

Shielding gases should be stored in an upright position to ensure their proper functioning and safety. Storing them upright prevents any leakage or damage to the gas cylinders. If the cylinders are stored horizontally, there is a higher risk of gas leakage, which can be hazardous. Additionally, storing the cylinders upright allows for easier identification and access to the specific gas needed for a particular application. Therefore, it is essential to store shielding gases in an upright position to maintain their integrity and ensure a safe working environment.

Skin exposure to carbon dioxide and nitrogen should be avoided because both gases are cold enough to cause frostbite. Carbon dioxide exists in a solid state as dry ice, which can cause frostbite upon contact with the skin. Nitrogen, on the other hand, is often used in cryogenic applications and can cause severe frostbite if it comes into contact with the skin. Therefore, it is important to avoid skin exposure to both carbon dioxide and nitrogen to prevent frostbite.

Compressed gas cylinders need to be secured in an upright position at all times to ensure their stability and prevent any potential hazards. Storing cylinders upright helps to prevent them from falling or tipping over, which could result in leaks, damage, or injury. Additionally, keeping the cylinders upright allows for easier identification of the contents and proper access to the valves. This position also ensures that the pressure relief devices are in the correct orientation, allowing for the safe release of pressure if needed.

The statement suggests that it is important to keep cables off metal tables or any grounding surfaces. This is because metal tables and grounding surfaces can conduct electricity and may cause electrical shocks or damage to the cables. Therefore, it is advisable to keep cables away from such surfaces to ensure safety and prevent any potential electrical hazards.

Oxygen cylinders should be protected against excessive temperature rises because high temperatures can cause the gas inside the cylinder to expand rapidly, leading to a dangerous increase in pressure. This can potentially result in the cylinder rupturing or exploding, posing a significant safety risk. Therefore, it is important to ensure that oxygen cylinders are stored and handled in environments where temperature fluctuations are minimal to prevent any potential accidents or hazards.

The statement is true because when using the Shielded Metal Arc Welding (SMAW) process, it is necessary to disconnect and remove the electrode holders and cables after completing the welding task. This is important for safety reasons as it helps prevent accidental contact with the live electrical components and reduces the risk of electrical shock or fire hazards. Additionally, removing the electrode holders and cables also helps in maintaining the equipment and preventing any damage or wear.

Water-cooled systems rely on the flow of water to dissipate heat and prevent overheating. If the water is not turned off when shutting down the system, it can lead to water leakage, damage to components, and potential electrical hazards. Therefore, it is important to ensure that water-cooled systems have the water turned off before shutting them down to avoid any potential issues.

Oxygen under pressure may react violently in the presence of oil or grease, which is why all oxygen fittings and equipment should be kept free of oil and grease. This is because the high pressure of oxygen can cause oil or grease to ignite or explode, posing a significant safety hazard. Therefore, it is crucial to ensure that oxygen systems are properly maintained and free from any potential sources of ignition.

Liquid oxygen cylinders have a double wall construction to help maintain a vacuum, and such cylinders should be handled with extreme care. This is because liquid oxygen is highly reactive and can easily ignite when it comes into contact with flammable materials. The double wall construction helps to prevent any leaks or ruptures that could lead to oxygen escaping and potentially causing a fire or explosion. Therefore, it is crucial to handle liquid oxygen cylinders with caution to ensure the safety of everyone involved.

Valve protection caps should not be used for lifting cylinders.

Natural gas should be used just like any other fuel gas, whether it is obtained from a cylinder or a piped-in supply. This means that it should be handled and used with the same precautions and safety measures as any other fuel gas. Regardless of the source, natural gas is a combustible substance and should be treated with respect to prevent accidents or hazards. Therefore, the statement "Whether used from a cylinder or from a piped-in supply, natural gas should be used just like any other fuel gas" is true.

Nonflammable shielding gases such as argon, nitrogen, carbon dioxide, and helium can displace oxygen in the air. This means that when these gases are released and accumulate in an enclosed space, they can reduce the oxygen levels, leading to a potential risk of asphyxiation for anyone in that area. Therefore, it is important to store these gases in well-ventilated areas to prevent the displacement of oxygen and ensure the safety of individuals.

Valve protection caps should be in place and securely fastened while stored to ensure that the valves are protected from any potential damage or contamination. This helps to maintain the integrity of the valves and prevent any unwanted leaks or malfunctions.

Cylinders should be stored in a well-protected, well-ventilated, dry location inside buildings to ensure safety. They should be kept at least 20 feet away from highly combustible materials. This distance is necessary to minimize the risk of fire or explosion, as combustible materials can easily ignite if they come into contact with cylinders containing flammable gases.

Oxygen cylinders should never be stored near any other fuels because oxygen greatly enhances combustion. When oxygen comes into contact with flammable materials, it can cause them to ignite and burn more rapidly and intensely. Storing oxygen cylinders near other fuels increases the risk of fire and explosion. To ensure safety, it is crucial to store oxygen cylinders separately from any other fuels to prevent accidents and potential hazards.

The correct answer is to pay careful attention to the actual time you spend welding. This is because the given information states that the GTAW welding machine has a duty cycle of only 10 percent. This means that the machine can only operate for 10 percent of the time before it needs to cool down. Therefore, it is important to monitor the time spent welding to ensure that it does not exceed the duty cycle and cause the machine to overheat.

Store cylinders on fireproof flooring only to ensure safety and prevent any potential fire hazards. Fireproof flooring is designed to resist the spread of fire and can help contain any flames or heat that may be generated from the cylinders. This reduces the risk of fire spreading to other areas of the store and minimizes the potential damage that could occur. Using fireproof flooring is a precautionary measure that helps protect both the store and its occupants from the dangers associated with storing cylinders.

When work is finished, when cylinders are moved at any time, or when cylinders are empty, cylinder valves shall be closed. This means that the cylinder valves should be closed when there is no gas or substance left in the cylinders. This is important for safety reasons as it prevents any accidental release of gases or substances that could be hazardous. Closing the valves when the cylinders are empty ensures that they are properly secured and reduces the risk of any accidents or leaks.

The correct answer is to operate the machine no more than 2 minutes out of each 10 minute period. This is because the GTAW machine has a 20 percent duty cycle, which means it can only be operated for 2 minutes out of every 10 minutes. Therefore, to ensure that the machine does not overheat and to adhere to the duty cycle, it is important to limit the operating time to 2 minutes within each 10 minute period.

The statement is false because acetylene should never be withdrawn from a cylinder at pressure above 15 psi. Acetylene is a highly flammable gas and becomes unstable and explosive at higher pressures. To ensure safety, it is recommended to withdraw acetylene at pressures below 15 psi.

Using only solvents and rags to clean cables and hoses is not recommended because it may not effectively remove dirt, grease, or other contaminants. Additionally, solvents can be flammable and may pose a safety risk if not used properly. It is important to follow the manufacturer's recommendations for cleaning cables and hoses, which may include using specific cleaning products or methods.

Oxygen should be stored with the valve end up to prevent any leakage or accidental release of the gas. Storing it in this position ensures that the valve remains tightly closed and reduces the risk of oxygen escaping from the container. This is important because oxygen is highly flammable and can pose a significant fire hazard if not handled and stored properly. By storing it with the valve end up, the likelihood of any accidents or mishaps related to oxygen storage is minimized.

Interchanging gas and water hoses without purging them first can be dangerous. Gas hoses are designed to handle the specific requirements of gas flow, while water hoses are designed for water flow. Interchanging them without purging can lead to gas leakage or water contamination, both of which can have serious consequences. Therefore, it is important to always purge the hoses before interchanging them to ensure safety.

The statement is false because acetylene can be safely used from a cylinder lying on its side. Acetone is used to stabilize acetylene and prevent it from becoming explosive, and it is stored in a porous material within the cylinder. When the cylinder is upright, the acetone is in contact with the acetylene gas. However, when the cylinder is lying on its side, the acetone is still contained within the porous material and does not mix with the acetylene gas. Therefore, there is no risk of explosion when using acetylene from a cylinder lying on its side.