chapter 12- lesson 6

What is the primary function of disinfectants according to the introduction?

• To improve the smell of inanimate surfaces

• To reduce or eliminate pathogenic microorganisms on inanimate surfaces

• To clean dirty floors and walls

• To remove stains from clothing

Which of the following is not listed as an example of an alkali used as a disinfectant?

• Sodium hydroxide

• Calcium oxide

• Sodium hypochlorite

• Potassium hydroxide

What is a characteristic of chlorine when used as a disinfectant?

• It has a pleasant odor

• It is ineffective as a bleaching agent

• It degrades when exposed to light

• It is most effective in a concentration of 5%

What is the concentration range of sodium hypochlorite (household bleach) when used as a disinfectant?

• 0.05% to 0.2%

• 1% to 5%

• 0.5% to 1%

• 2% to 10%

According to the text, what should be done before applying lime as a disinfectant to animal skin?

• The animals should be washed thoroughly

• The lime should be diluted with water

• The animals should be removed from the grounds

• The lime should be mixed with other disinfectants

Quaternary ammonium is an effective disinfectant when applied to clean, hard surfaces because it has:

• Pleasant odor and is non-irritating

• Acceptable odors and are non-irritating to those who have chemical sensitivities

• Offensive odor and is irritating to those with chemical sensitivities

• No odor and is completely safe for all surfaces

Phenol, when used as a disinfectant, is not recommended for food contact surfaces because it:

• Is too mild as a disinfectant

• Is safe for all types of surfaces

• Can cause corrosion and has an offensive odor

• Is the most effective disinfectant available

Proper handling of disinfectants requires that:

• A solution too weak will be effective

• Spills and splashes may injure operator or patient

• Combining chemicals can reduce the effectiveness of the active ingredients

• Organic material may increase the effectiveness of the disinfectant

Which of the following is a reason why surfaces are to be cleaned prior to chemical disinfection?

• To ensure a pleasant smell after disinfection

• To prevent corrosion of the surfaces

• To remove organic matter that can inactivate disinfectants

• To make the disinfectant smell better

Why is it important to dilute bleach properly when using it as a disinfectant?

• To prevent damage to surfaces and materials

• To enhance its pleasant smell

• To increase its shelf life

• To make it less effective as a disinfectant