Certified And Registered Central Service Technician (CRCST) Practice Exam

Critical items are classified as items that are introduced directly into the bloodstream or other normally sterile areas of the body. These items have a high risk of causing infection if not properly sterilized or if contaminated. It is crucial to ensure that critical items are properly cleaned, sterilized, and handled to prevent the transmission of pathogens and ensure patient safety.

Sterilization is the correct answer because it refers to the process of completely destroying all forms of microorganisms, including bacteria, viruses, and spores. This process ensures that no viable microorganisms are present, making the object or area free from any potential sources of infection or contamination. High-level disinfection, thermal disinfection, and chemical disinfection may effectively kill most microorganisms but may not guarantee complete eradication, unlike sterilization.

To achieve a reasonable level of disinfection, alcohol must remain in wet contact with an item for a period of five to 10 minutes. This duration allows enough time for the alcohol to effectively kill bacteria and viruses on the surface. A shorter contact time may not be sufficient to fully disinfect the item, while a longer contact time may not provide any additional benefits and could potentially damage the item being disinfected. Therefore, five to 10 minutes is considered an appropriate timeframe for alcohol disinfection.

Thermal disinfection is a process of using heat to eliminate or reduce the number of microorganisms. It is an effective method because high temperatures can denature the proteins and enzymes of the microorganisms, leading to their destruction. The options "Heated chemicals" and "Heated glutaraldehyde" are incorrect as they suggest the use of heated substances, rather than heat itself. Prolonged high pressure steam is also incorrect as it specifies a specific form of heat, while the correct answer simply states "heat," which encompasses all forms of heat.

Ortho-phthalaldehydes would be the best choice for high-level disinfection of instruments. This is because ortho-phthalaldehydes have a broad spectrum of antimicrobial activity and can effectively kill a wide range of microorganisms, including bacteria, viruses, and fungi. They are also relatively fast-acting and have a low level of toxicity. Additionally, ortho-phthalaldehydes have good material compatibility and can be used to disinfect a variety of medical instruments without causing damage or corrosion.

Testing the minimum effective concentration in high-level disinfection solutions each time the solution will be used ensures that the solution is at the appropriate concentration to effectively kill microorganisms. This is important for ensuring the safety and efficacy of the disinfection process. Weekly or daily testing is not frequent enough to guarantee that the solution remains effective between tests. Testing is not limited to only when manual soaking systems are used, as the concentration of the solution can vary regardless of the method used.

Glutaraldehyde and ortho-phthalaldehydes are classified as high-level disinfectants because they have the ability to kill a wide range of microorganisms, including bacteria, viruses, and fungi. These disinfectants are effective against both vegetative and spore forms of microorganisms, making them suitable for use in healthcare settings where a high level of disinfection is required. Additionally, both glutaraldehyde and ortho-phthalaldehydes have a low level of toxicity and are compatible with a variety of materials, making them versatile options for disinfection purposes.

Antiseptics are used on living tissue to slow the growth of microorganisms. They are specifically designed to be used on animate (living) surfaces, such as skin, to prevent infection. Antiseptics work by killing or inhibiting the growth of bacteria, viruses, and fungi, thereby reducing the risk of infection. Unlike disinfectants, which are used on inanimate objects, antiseptics are formulated to be safe for use on the skin and other living tissues. Glutaraldehydes, halogens, and disinfectants are not specifically designed for use on living tissue, making antiseptics the correct answer.

Phenolics are classified as intermediate to low-level disinfectants because they have a broad spectrum of antimicrobial activity and can effectively kill a wide range of microorganisms, including bacteria, viruses, and fungi. However, they are not as potent as high-level disinfectants or sterilants, which can completely eliminate all forms of microbial life. Therefore, phenolics are considered suitable for disinfecting surfaces and medical equipment that do not require sterilization but still need effective disinfection.

Thermal disinfection refers to the use of heat to kill all microorganisms, except spores. This method is effective in destroying most bacteria, viruses, and fungi. It is commonly used in healthcare settings to sterilize medical equipment and instruments. Unlike sterilization, which kills all forms of life including spores, thermal disinfection only targets the vegetative forms of microorganisms. This process helps to reduce the risk of infection and ensure the safety of patients and healthcare workers.

Iodophors are a member of the chemical family known as halogens. Halogens are a group of elements that include iodine, chlorine, bromine, fluorine, and astatine. Iodophors are chemical compounds that contain iodine and are commonly used as disinfectants or antiseptics. They are effective against a wide range of microorganisms and are often used in medical and healthcare settings.

Quaternary ammonium compounds are a type of low-level disinfectant that is incompatible with soap. This means that when used together, the effectiveness of both the disinfectant and the soap may be compromised. It is important to note that soap is not considered a disinfectant on its own, but rather helps to remove dirt and germs from surfaces. Therefore, if quaternary ammonium compounds are used for disinfection, it is recommended to avoid using soap simultaneously to ensure the effectiveness of the disinfectant.

Technicians should not always wear latex gloves when using glutaraldehyde. While gloves are recommended for protection, they should be made of nitrile or neoprene, as glutaraldehyde can penetrate latex gloves and cause skin irritation or allergic reactions. Therefore, the statement is false.

High-level disinfectants are powerful disinfectants that are used to kill or inactivate a wide range of microorganisms. However, they can be deactivated or rendered ineffective by organic matter. Organic matter such as blood, bodily fluids, dirt, or debris can interfere with the disinfection process by binding to the disinfectant molecules and preventing them from effectively targeting and killing the microorganisms. Therefore, it is crucial to clean and remove any organic matter from the surfaces or objects before applying high-level disinfectants to ensure their effectiveness.

Water temperature is the key source of disinfection in an automated washer because high temperatures can kill or inactivate many types of microorganisms. Heat is able to denature proteins and disrupt cell membranes, effectively destroying the microorganisms. Hydrogen peroxide can also have disinfecting properties, but it is not the main source of disinfection in this case. Disinfecting detergent can help in the cleaning process, but it is not the primary source of disinfection.