192 PRINCIPLES OF DISINFECTION 



5. How can the effect of a certain degree of heat upon pathogenic bacteria 

 be ascertained? 



6. What is meant by an inhibiting degree of temperature upon a bacterium? 

 What by a germicidal effect? 



7. What is the optimum, what the maximum temperature of a bacterium? 



8. How is the effect of chemicals upon bacteria, both their antiseptic and 

 their germicidal effect, ascertained? 



9. What precautions are necessary to get trustworthy values for concen- 

 tration and time? 



10. What factors influence the effect of an antiseptic or disinfectant upon 

 bacteria? 



11. Describe the silk thread and the garnet method of testing germicidal 

 values. 



12. What is the difference between dry and moist heat as a germicide? 



13. Give the effect upon the germicidal value of moist heat of temperature, 

 pressure, complete or partial saturation, admixture with antiseptics. 



14. What is the effect of low temperatures upon pathogenic bacteria? 



15. What is the effect of direct sunlight and diffuse light upon pathogenic 

 bacteria? 



16. Give some examples as to the effect on pathogenic bacteria. 



17. What is the effect of diffuse daylight? 



18. What is the effect of drying out bacteria? 



19. What is the effect of electrical currents upon fluid cultures of pathogenic 

 bacteria? 



20. What is the effect of the axrays? 



21. What is the effect of radium emanations? 



22. What are the properties of an ideal disinfectant? Name a number of them. 



23. Describe the germicidal properties of corrosive sublimate in solution under 

 varying conditions. 



24. How should it be used in disinfecting a barn infected with anthrax bacilli 

 and spores? 



25. Describe the use of caustic lime as a disinfectant. 



26. Describe the use of chlorinated lime as a disinfectant. When is it used in 

 particular? 



27. What is the effect of a 4 per cent, solution of permanganate of potash upon 

 anthrax spores? 



28. Give advantages and disadvantages of carbolic acid as a disinfectant. 



29. What is an aldehyde? What is formaldehyde? 



30. What is formol or formalin? 



31. How is a 1 per cent, solution of formaldehyde prepared from a good com- 

 mercial formalin? 



32. What is meant by polymerization? What is the polymerization product 

 of formalin? Is it a gas like the latter? 



33. How can paraform be used as a disinfectant? 



34. How does a 4 per cent, solution of formalin compare with corrosive sub- 

 limate and with carbolic acid? 



35. What kind of an acid is carbolic acid? 



36. How should formalin be used as a disinfectant? How much for each 1000 

 cubic feet of space? 



37. What is the Breslau method of using formalin? 



38. How is a space to be disinfected by formalin prepared? 



39. How can the unpleasant pungent irritating smell of formalin be removed 

 after disinfecting a space with it? 



40. Discuss the value, advantages, and disadvantages of sulphur dioxide as a 

 disinfectant. 



41. How is it prepared? How much is required for each 1000 cubic feet of 

 space? 



42. Discuss the value of 100 per cent, and of 50 per cent, alcohol as a disin- 

 fectant. 



43. What is the difference between disinfection and sterilization? 



