Manual of basic techniques for a health laboratory - libdoc.who.int

82 Manual of basic techniques for a health laboratoryContainers for stool specimensIf the lavatory is not connected to a septic tank, fill the jars containing stools with a5% solution of cresol (see page 83) or a similar disinfectant. Leave for 6 hours.Empty into the lavatory.If the lavatory is connected to a septic tank, cresol or other disinfectants should notbe added to the stools before disposal. Clean the jars with detergent and water, asdescribed on page 80.Sputum pots and tubes containing pus or CSF specimensThere are several possible methods.Using an autoclave 1This is the best method.1. Place the containers in the autoclave and sterilize for 30 minutes at 120°C.2. After the containers have cooled, empty the contents into the sink or lavatory.3. Clean with detergent and water, as described on page 80.Boiling in detergentKeep a large pan especially for this purpose.Boil sputum pots for 30 minutes in water containing washing powder (60g perlitre of water) (Fig. 3.62).Using formaldehyde solution or cresolPour into each sputum pot either:— 10ml of undiluted formaldehyde, 10% solution (reagent no. 28), or— 5ml of 5% cresol (see page 83).Leave for 12 hours.Fig. 3.62 Cleaning sputum pots byboiling in detergentUrine bottlesEmpty the bottles into the lavatory.Fill them with either:— a 10% solution of household bleach (see page 84), or— a 5% solution of cresol (see page 83).Leave for 4 hours.Test-tubes containing blood specimensTest-tubes of fresh blood collected on the same day should be:— rinsed in cold water— left to soak in a detergent solution (see page 80).Test-tubes of “old” blood kept for several days at room temperature may contain largenumbers of microorganisms. They should be:—filled with a 10% solution of household bleach (see page 84)— left for 12 hours and then— rinsed and cleaned.1For further information, see section 3.5.5.