CHAPTER- 2

LITERATURE - SURVEY

2.0	SOURCES AND GENERARTION OF BIO- MEDICAL WASTES.

2.1	Sources of Bio-Medical Waste:

        The sources of biomedical waste which can cause severe health hazards can be categorized into major and minor sources depending upon the quantity   produced. However the scope of the present work is limited to the study of Bio-medical wastes generated in hospitals in metro cities.
(a)	Major Sources

        The major sources of bio-medical waste include hospitals, other health-care establishments and related laboratories and research centers. Hospital waste comprises of waste from University hospital, General   hospital and  District hospital. Other health care establishments consists of waste from emergency medical care service, health-care centers and dispensaries,   obstetric and maternity clinics , outpatient clinics , dialysis centers, first-aid posts and sick bays, long-term health care establishments and hospices transfusion center and military medical services 
        Related laboratories and research centers includes medical and biomedical    Laboratories, biotechnology laboratories and institutions, medical research centers,                 mortuary and autopsy centers  , animal research and testing, blood banks and blood collection services and nursing homes for the elderly.

(b)Minor Sources

        The Minor sources of bio-medical waste are small health-care establishments  
specialized health-care establishments and non-health activities involving                                                intravenous or subcutaneous interventions.
        Small health-care establishments comprises of physicians offices, dental clinics, acupuncturists and chiropractors.
                          
        Specialized health-care establishments includes convalescent nursinghomes,  psychiatric hospitals and disabled persons' institutions.
        Non-health activities involving intravenous or subcutaneous interventions consists of cosmetic ear-piercing and tattoo parlor, illicit drug users, funeral services ambulance services and home treatment.

2.2	Bio-Medical Waste Generation  

        There are several factors on which the biomedical waste generation depends. The identified factors are type of health care unit, hospital specialization, no of persons treated on daily bases ,proportion of research work items and the economical status of the patient etc.
.
Table 2.1: Bio-Medical waste generation according to national income level
        Extensive literature survey was done at national level and the various data was tabulated in the following manner as given in the table below:

National income level	Annual waste generation, (kg/head of population)	
High-income countries:
All health-care waste
 Hazardous health-care waste	
1.1-12.0
0.4-5.5	
Middle-income countries:
All health-care waste
Hazardous health-care waste	
0.8-6.0
0.3-0.4	
Low-income countries:
All health-care waste	
0.5-3.0	

         Sources: Commission of the Europe all Union (1995), Halbwachs (1994),   
         Durand (1995).
             
               From the above table it is seen (as expected) that the waste generation is   
               dependent on the per capita income of a country.
Table 2.2: Bio-Medical waste generation according to Source Size

Source	Daily waste generation (kg/bed)	
University hospital	4.1-8.70	
General hospital	2.1-4.20	
District hospital	0.5-1.80	
Primary health-care hospital	0.05-0.20	

Sources: Economopoulos (1993

              
        The amount of radioactive Bio-Medical waste is generally extremely small compared with the radioactive waste produced by the nuclear industry. The developing countries that have not performed their own surveys of bio-medical waste may find the following estimates for average distribution of bio-medical wastes useful for preliminary planning of waste management:

•	80% general biomedical waste, which may be dealt with by the normal domestic  and urban waste management system;
•	15% pathological and infectious waste;
•	1 % sharps waste;
•	3% chemical or pharmaceutical waste;
•	Less than 1 % special waste, such as radioactive or cyostatic waste, pressurized containers or broken thermometers and used batteries.

Table 2.3: Bio-Medical waste generation at international level:
                 
        Literature survey was conducted for both developed and developing countries as given in the following table:
Region	Daily waste generation (kg/bed)	
North America	7-10	
Western Europe	3-6	
High-income countries
Middle-income countries	2.5-4
1.8-2.2	
Latin America	3	
Eastern Europe	1.4-2	
Eastern Mediterranean	1.3-3	
France	2.5	
Netherlands	2.7	
USA	4.2	

Sources: Durand (personal communication, 1995), Johansson (1997).

        Before further planning is undertaken, health-care establishments should make estimates of their own waste production, particularly for hazardous health-care wastes. The estimated number of beds and estimated quantity of Bio-medical waste in India is given in Table 2.4

 Table 2.4 Estimated quantity of bio medical waste in the country

S.No.	States/Union Territories	Total no of Beds	Estimated quantity of bio-medical No. of waste generation (kg/day)	
1.	Andhra Pradesh	26791	6698	
2.	Arunachal Pradesh	2476	619	
3.	. Assam	12661	3164	
4.	Bihar	29090	7273	
5.	Goa	3644	911	
6.	Gujarat	58984	14746	
7.	Haryana	7028	1757	
8.	 Himachal Pradesh	3852	963	
9.	Jammu & Kashmir'	8202	2051	
10.	Karnataka	37929	94811	
11.	Kerala	77199	19300	
12.	Madhya Pradesh	18141	4534	
13.	Maharastra	78920	19730	
14.	 Manipur	1561	299	
15.	Meghalaya	1867	467	
16.	Mizoram	1304	3262	
17.	Nagaland	1050	263	
18.	Orissa	14494	3624	
19.	Punjab	14671	3668	
20.	Rajasthan	20465	5115	
21.	Sikkim	575	144	
22.	Tamil Nadu	48780	12195	
23.	Tripura	1730	433	
24.	Uttar Pradesh	47278	11820	
25.	West Bengal	54767	13692	
26.	A&N Islands	576	144	
27.	Chandigarh	500	125	
28.	Dadra & Nagar Haveli	70	18	
29.	Daman & Diu	150	38	
30.	Delhi	18770	4693	
31.	Lakshadweep	70	18	
32.	Pond cherry	2608	652	
	Total 	596203	149051	

        As  per expectation the amount of waste generated/kg/day is directly dependent on he no of people taking medical treatment in hospital

Source: Manual on Hospital waste management. May 2000. CPCB.

2.3	Classification of Biomedical Waste 
         
        For efficient waste management system,the classification of waste is an important criteria. The waste may be categorized into sharps, soiled wastes, disposable, anatomical waste, discarded medicine, chemical waste etc.  

        Bio-medical waste includes all the waste generated by hospitals, research facilities and laboratories. In addition, it includes the waste originating from minor or scattered sources such as that produced in the course of health care undertaken in the home. Between 75% and 90 % of the waste produced by hospitals is comparable to domestic waste. It is created mostly from administrative and housekeeping functions of health care units and may contain waste generated during maintenance of health care premises. The remaining 10-25% of hospital waste is generated as hazardous and may create a various health risks.

Table 2.5(a) gives the categorization of biomedical waste as recommended by WHO. Table 2.5(b) gives the categorization of bio medical waste as per the government of                 India's Notification on biomedical waste the details of the various categories of bio medical waste are summarized in following paragraph.

 Table 2.5(a): Categories of biomedical waste as recommended by WHO

Sl. No.	Waste Category 	Description	
1.	Infectious waste	Waste suspected to contain pathogens e.g. waste from isolation wards; tissues (swabs), materials, or equipment that have been in contact with infected patient; excreta.	
2.	Pathological waste	Human tissues or fluid e.g. body parts; blood and other body fluid; fetuses	
3.	Sharps	Sharps waste e.g. needles; infusion sets scaples knives blades, broken glass.	
4.	Pharmaceutical waste	Waste containing pharmaceuticals e.g.
Pharmaceuticals that are expired or no longer needed items contaminated by or containing pharmaceuticals (bottles, boxes).
	
5.	Genotoxic waste	Waste containing substances with genotoxic properties e.g. waste containing cytostatic drugs (often used m cancer therapy); genotoxic chemicals.	
6.	Chemical waste	Waste containing chemical substances e.g.
Laboratory reagents; film developer; disinfectants that are expired or no longer needed; solvents.
	
7.	Waste with high content of heavy metals 	Batteries; broken thermometers; blood pressure content of heavy gauges; etc
.
	
8.	Pressurize containers 	Gas cylinders, gas cartridges; aerosol cans	
9.
	Radioactive waste	Waste containing radioactive substances Waste containing unused liquids from radiotherapy or laboratory research; contaminated glassware, packages, or absorbent paper; urine and excreta from patients treated or tested with unsealed radionuclide;
sealed sources

Table 2.5(b) : Categories of biomedical waste as per Govt. of India : Notification
S.No	Option	Waste category	
1.	Category No. 1	Human Anatomical waste 	
2.	Category No.2	Animal waste 	
3.	Category No.3	Microbiology & Biotechnology Waste 	
4.	Category No.4	Waste sharps 	
5.	Category No.5	Discarded medicines and Cytotoxic drugs	
6.	Category No.6	Soiled Waste 	
7.	Category No. 7	Solid waste 	
8.	Category No.8	Liquid waste 	
9.	Category No.9	Incineration ash 	
10.	Category No. 10	Chemical waste 	

2.4 	Legislations for Bio -Medical Waste Management

	International agreements and underlying legislative and regulatory principles:

        International agreement is based on number of following principles that govern either public health management of hazardous waste. These principles outlined below should be taken into consideration when national legislation or regulations governing bio-medical waste management are formulated:
        These principles are signed by more than 100 countries, concerns tran boundary movements of hazardous waste; it is also applicable to health-care waste. Countries that signed the Convention accepted the principle that the only legitimate tran boundary shipments of hazardous waste are exports from countries that lack the facilities or expertise to dispose safely of certain wastes to other countries that have both facilities and expertise. Exported waste should be labeled according to the UN recommended standards:
        The "polluter pays" principle implies that all producers of waste are legally and financially responsible for the safe and environmentally sound disposal of the waste they produce. This principle also attempts to assign liability to the party that cause damage.
        The "precautionary" principle is a key governing health and safety protection. When the magnitude of a particular risk is uncertain, it should be assumed that this risk is significant, and measures to protect health and safety should be designed accordingly. The "proximity" principle recommends that treatment and disposal of hazardous waste take place at the closest possible location to its source in order to minimize the risks involved in its transport. According to a similar principle, any community should recycle dispose of the waste it produces, inside its own territorial limits.
2.5      Biomedical Waste Management and Planning

(1) 	The need for planning

        Formulation of objectives and planning for their achievement is necessary to  improve bio-medical waste management at the national, regional, and local level. Planning requires the definition of a strategy that will facilitate careful implementation of the necessary measures and the appropriate allocation of resources according to the identified priorities. This is important for the motivation of authorities, bio-medical workers, and the public, and for defining further actions that may be needed.Surveys on the generation of waste will be the basis for identifying opportunities and setting targets for waste minimization, reuse and recycling, and cost reduction.

(2) 	International recommendations for waste management

        The United Nations Conference on the Environment and Development (UNCED) in 1992 led to the adoption of Agenda 21, which recommends a set of measures for waste management. The recommendation may be summarized as follows:
•	Prevent and minimize waste production;
•	Reuse or recycle the waste to the extent possible;
•	Treat waste by safe and environmentally sound methods;
•	Dispose of the final residues by landfill in confined and carefully designed sites.

(3) 	      Waste management plan for a health-care establishment

(a)	Assignment of responsibilities

        The appropriate management of bio-medical waste depends mainly on good administration and organization but also requires adequate legislation and financing, as well as active participation by trained and informed staff. The head of the hospital should form a waste management team to develop a waste management plan. The team should have the following members:

1.	Head of Hospital (as chairperson). 
2.	Heads of Hospital Departments.  
3.	Infection Control Officer.  
4.	Chief Pharmacist.  
5.	Radiation Officer.
6.	Matron (or Senior Nursing Officer) .
7.	Hospital Manager .
8.	Hospital Engineer .
9.	Financial Controller
10.	Waste Management Officer (if already designated).

       In certain establishments, the structure may include a Hospital Hygienist, in addition to or instead of the Infection Control Officer, to address specific problems relating to hospital hygiene. In such cases, some or all of the duties of the Infection Control Officer specified below will be carried out by the Hospital Hygienist. The members of the waste management team in writing, informing each of them of their duties and responsibilities should be formally appointed by the Head of Hospital as outlined in the following sections. He or she should appoint a Waste Management Officer with overall responsibilities for the development, of the hospital waste management plan and for the subsequent day-by-day operation and monitoring of the waste disposal system. This post may be assigned to the Hospital Engineer depending on availability of relevant staff. Hospital Manager to any other appropriate staff member at the discretion of the Head of Hospital.

(b)	Management structure, liaison paths, and duties

      A typical hospital waste management structure with line management responsibilities and liaison paths between key personnel involved in the handling of healthcare waste. This structure may be adjusted to the particular needs of each hospital. The sharing of duties of key personnel in large hospitals is described in the following paragraphs; in smaller hospitals, one individual may fulfill two or more sets of responsibilities, but the same principles will apply.
1.	Hospital Engineer
2.	Head of Environmental Services Departments
3.	Heads of Medical and Dental Engineering 
4.	Pharmacy 
5.	Radiology 
6.	Laboratory
7.	Blood Bank
8.	Catering
9.	Housekeeping
10.	Internal Transportation System
11.	Administration
12.	Finance
13.	Supporting Staff
14.	Heal of Hospital
15.	Hospital attendants and ancillary workers
16.	liaison path
17.	line management paths

2.6 	  Waste Minimisation
            
        The policies and practices that should be implemented for reduction of waste generation are depends upon the 4R,s that is refuse, reuce, recycle and reuse..

2.7	 Handling Storage and Transportation of Bio- Medical Waste

1 	 Waste segregation and packaging

          Segregation  and identification of the waste is the key to minimizations and management of bio-medical waste. Appropriate handling, treatment, and disposal of waste by type reduce costs and do much to protect public health. Segregation should always be the responsibility of the waste producer, should take place as close as possible to where the waste is generated, and should be maintained in storage areas and during transport. The same system of segregation should be in force throughout the country. The following practices are  recommended in addition to the color-coding of waste containers:

•	General heath-care waste should join the stream of domestic refuse for disposal.
•	Sharps should all be collected together, regardless of whether or not they are contaminated. Containers should be puncture-proof (usually made of metal or plastic and fitted with covers. They should be rigid and impermeable so that they safely retain not only the sharps but also any residual liquids from syringes. To discourage abuse. Containers should be tamper-proof (difficult to open or break) and needless and syringes should be rendered unusable. Where plastic or metal  containers are unavailable or too costly, containers made of dense cardboard are recommended.
•	Bags and containers for infectious waste should be marked with the international infectious substance symbol 
•	Highly infectious waste should, whenever possible, be sterilized immediately by autoclaving. It therefore needs to be packaged in bags that are compatible with the proposed treatment process: red bags, suitable for autoclaving, are recommended.
•	Cytotoxic waste, most of which is produced in major hospital or research facilities, should be collected in strong, leak-proof containers clearly labeled cytotoxic wastes 
•	Small amounts of chemical or pharmaceutical waste may be collected together with infectious waste.
•	Large quantities of obsolete or expired pharmaceuticals stored in hospital wards or departments should be returned to the pharmacy for disposal. Other pharmaceutical waste generated at this level, such as spilled or contaminated drugs or packaging containing drug residues should not be returned because of the risk of contaminating the pharmacy; it should be deposited in the correct containers at the point of production.
•	Large quantities of chemical waste should be packed in chemical-resistant containers and sent to specialized treatment facilities (if available). The identity the chemicals should be clearly marked on the containers: hazardous chemical wastes of different types should never be mixed.
•	Waste with a high content of heavy metals' (e.g. cadmium or mercury) should be collected separately.
•	Aerosol containers may be collected with general bio-medical waste once they are completely empty, if the waste is not destined for incineration.
•	Low-level radioactive waste (e.g. swabs, syringes for diagnostic or therapeutic use) may be collected in yellow bags or containers for infectious waste if there are destined for incineration.
        Since costs for safe treatment and disposal of hazardous bio-medical waste are typically more than 10 times higher than those for general waste, all general, i.e. non-hazardous, waste should be handled in the same manner as domestic refuse and collected in black bags. No health-care waste other than sharps should be deposited in sharps containers, as these containers are more expensive than the bags used for other infectious waste. Measure of this sort help to minimize the costs of bio-medical waste collection and treatment. When disposable syringes are used, for example, the packaging should be placed in the general waste bin and the used syringe in the yellow sharps container. In most circumstances, the needle should not be removed from syringe because of the risk of injury, if removal of the needle is required, special care must be taken.
        Appropriate containers or bags holders should be placed in all locations where particular categories of waste may be generated. Instructions on waste separation and identification should be post.

2 	On-site collection, transport, and storage of waste 

(a)	Collection

        It should be ensured that waste bags are tightly closed or sealed when they are about three-quarters full. Light-gauge bags can be closed by tying the neck, but heavier-gauge bags probably require a plastic sealing tag of the self-locking type. Bags should not be closed by stapling. Sealed sharps containers should be placed in a labeled, yellow infectious bio-medical waste bag before removal from the hospital ward or department. Waste should not be allowed to accumulate at the point of production. A routine programme for their collection should be established as part of the bio-medical waste management plan. The recommendations to be followed by the ancillary workers in charge of waste collection:

•	Waste should be collected daily (or as frequently as required) and transported to the destination  central storage site.
•	No bags should be removed unless they are labeled with their point of production (hospital and ward or department) and contents.
•	The bags or containers should be replaced immediately with new ones of the same type.
•	A supply of fresh collection bags or containers should be readily available at all locations where waste is produced.

(b)	 Storage

        Inside the health-care establishment or research facility, a storage location for bio-medical waste should be designated. The waste, in bags, or containers, should be stored in a separate area, room, or building of a size appropriate to the quantities of waste produced and the frequency of collection. The methods and recommendations for the storage area and the equipment are as given below:
•	Storage times for bio-medical waste (i.e. the delay between production and treatment) should not exceed the following if a refrigerated storage room. is not available
•	Temperature climate : 72 hours in winter 48 hours in summer Warm climate : 48 hours during the cool season 24 hours during the hot season Cytotoxic waste should be stored separately from other bio-medical waste in a designated secure location.
•	Radioactive waste should be stored in containers that prevent dispersion, behind lead shielding. Waste that is to be stored during radioactive decay should be labeled with the type of radionuclide, the date, and details of required storage conditions.
•	The storage area should have an impermeable, hard-standing floor with good drainage; it should be clean and disinfect.       
•	There should be a water supply for cleaning purposes.
•	The storage area should afford easy access for staff in charge of handling the waste.
•	It should be possible to lock the store to prevent access by unauthorized persons.
•	Easy access for waste-collection vehicles is essential.
•	There should be protection from the sun.
•	The storage area should be inaccessible for animals, insects, and birds.
•	There should be good lighting and at least passive ventilation.
•	The storage area should not be situated in the proximity of fresh food stores or food preparation areas.
•	A supply of cleaning equipment, protective clothing, and waste bags or containers should be located conveniently close to the storage area.

3		On-site transport 

       Wheeled trolleys, containers, or carts that are not used for any other purpose and meet the following specifications are used for the transportation of biomedical waste within the hospital or other facility : 

•	Easy to lead and unload;
•	No sharp edges that could damage waste bags or containers during loading and unloading.
•	Easy to clean.
•	The vehicles should be cleaned and disinfected daily with an appropriate disinfectant.
•	All waste-bag seals should be in place and intact at the end of transportation.

4 	Off-site transportation of waste  

•	Regulation and control system 
•	Special packaging requirements for off-site transport 
•	Labeling 
•	Routing 

2.8	Treatment Technologies

       As per the CPCB manual on HWM, there are five broad categories of hospital waste treatment technologies which are as follow

1 	Mechanical Process 

       These are processes used to change the physical form or characteristics of the waste either to facilitate waste handling or to process the waste in conjunction with other treatment steps. The two primary mechanical processes are compaction and shredding. Compaction involves compressing the waste into containers to reduce its volume. Shredding, which also includes granulation, grinding, pulping etc. is used to break the waste into smaller pieces. 

2 	Thermal Processes 

       In this processes heat is used to decontaminate or destroy medical waste at temperatures ranging from 49°C to 91°C. Low-heat systems and high-heat systems are the two categories of thermal processes. Low-heat systems use steam, hot water or electromagnetic radiation to heat and decontaminate the water.. High heat systems employ combustion, hydrolysis and high temperature plasmas to decontaminate and destroy the waste. The basic thermal treatment processes are as follows:
(a)	      Autoclaving 

        Autoclave (steam sterilization) is a low-heat thermal process and is designed to bring steam into direct contact with the waste in a controlled manner and for sufficient time to disinfect the waste. The three basic types of steam autoclave systems are gravity, pre vacuum, and retort systems. Gravity type autoclaves, in which pressure alone is used to evacuate air from the treatment chamber, typically operate with standard temperatures of about 121°C. These systems require a typical cycle time of approximately 60-90 minutes in order to achieve full steam penetration into the most densely packed waste loads. Pre-vacuum type autoclave systems evacuate air from the treatment chamber using vacuum pumps. This enables them to reduce cycle times to about 30 - 60 minutes, as the time to heat the air within the chamber is eliminated. Pre-vacuum systems typically operate at about 132°C. Retort type autoclaves comprise large volume treatment chambers designed for much higher steam temperatures and pressures, and therefore their cycle times can be substantially less than those of the other systems. 

(b)	      Microwave Treatment

       Microwave heating occurs inside the waste material unlike other thermal treatment systems, which heats wastes externally,. This process involves pre-shredding the waste, injecting it with steam, and heating it for 25 minutes at 95°C under a series of microwave units..
(c)	      Incineration 

       High-temperature combustion under controlled conditions is used in incineration to convert wastes containing infectious and pathological material to inert mineral residues and gases. The three types of incinerators used for hospital waste treatment are multiple-hearth, rotary kiln, and controlled air. All three types can have primary and secondary combustion chambers to ensure maximum combustion of the waste. The primary chamber is for solid-phase combustion, whereas the secondary chamber is for gas-phase combustion. The rotary kiln is a cylindrical refractory-lined shell that is mounted at a slight incline from the horizontal plane to facilitate mixing the waste materials with circulating air. Rotary-kiln systems usually have a secondary combustion chamber after the kiln to ensure complete combustion of the waste. Under conditions of both low and excess stochiometric oxygen requirements, controlled-air incinerators bump waste into two or more chambers. In the primary chamber, waste is dried, heated, and burned at 40 - 80% of the stochiometric oxygen requirement. Combustible gas produced by this process is mixed with excess air and burned in the secondary chamber at usually between 100 - 150% of the stochiometric requirement. A supplementary fuel burner is used to maintain elevated gas temperatures and provide for complete combustion.

(d)	      Plasma Systems 

       A plasma torch or burner is utilised for heating the waste to super-high temperatures. Plasma is a material in which the temperatures are so high that some of its electrons re separated from its atoms. Some plasma-fired systems are reportedly designed to operate with furnace temperatures of as high as 10,000°C. These systems are, in many respects, very similar to incineration systems except that conventional combustion does not take place. The plasma-fired chambers operate in an oxygen-deficient mode, and off-gases need to be com busted separately. The residue produced is a glass-like substance, rather than a particulate ash typical of incinerators.

3	         Chemical Processes 

       Chemical treatment is synonymous with chemical disinfection. Disinfectants used are mostly chlorine compounds, phenolic compounds, iodine, alcohols, hexachlorophene, formaldehydes, iodine-alcohol combinations, formaldehyde-alcohol combination etc. Most chemical disinfectants are used as aqueous solutions. Most of these systems start with a shredding step in order to provide sufficient contact between the waste and disinfectants. 
4 	Irradiation process 
	
        Irradiation is synonymous with electromagnetic or ionizing radiation. Processes utilizing Cobalt 60, and electron beam accelerator unit or electron beam gun, for irradiation sterilizing the medical waste have been developed. These systems require post shredding, to render the waste unrecognizable.
5          Biological Process 

        For treating biomedical waste a system is being developed using biological enzymes. It is claimed that biological reactions will not only decontaminate the waste but also cause the destruction of all the organic constituents so that only plastics, glass, and other inert will remain in the residues.

2.9 	Wastewater management : 

1          Management of liquid waste : 

       Strict limit on the discharge of hazardous liquids to sewers is the basic principle underlying effective wastewater management .

(a)	       Connection to a municipal sewage treatment plant 

        In countries that do not experience epidemics of enteric diseases and that are not endemic for intestinal helminthiasis, it is acceptable to discharge the sewage of biomedical waste to municipal sewers without pretreatment, provided that the following requirements are met:

•	The municipal sewers are connected to efficiently operated sewage treatments plants that ensure at least 95% removal of bacteria.
•	The sludge resulting from sewage treatment is subjected to anaerobic digestion, leaving no more than one helminthes egg per liter in the digested sludge.
•	The waste management system of the biomedical waste producer maintains high standards, ensuring the absence of significant quantities of toxic chemicals, pharmaceuticals, radionuc1ides, cyotoxic drugs, and antibiotics in the discharged sewage.
•	Excreta from patients being treated with cyotoxic drugs may be collected separately and adequately treated.
•	If these requirements cannot be met, the wastewater should be managed and treated. In normal circumstances, the usual secondary bacteriological treatment of sewage, properly applied, complemented by anaerobic digestion of sludge, can be considered as sufficient.
•	During outbreaks of enteric disease, during critical periods (usually in summertime because of warm weather, and in autumn because of reduced river water flow),effluent disinfection by chlorine dioxide (Cl02) or by any other efficient process is recommended. If the final effluent is discharged into coastal wasters close to shellfish habitats, disinfection of the effluent will be required throughout the year.
        When the final effluents or the sludge from sewage treatment plants are reused for agricultural or aqua cultural purposes, the safety recommendations should be respected. Many hospitals, in particular those that are not connected to any municipal treatment plant, have their own sewage treatment plants.

(b)	      Wastewater treatment 

        The following operations should be practiced for efficient on site treatment of biomedical waste:
•	Primary treatment 
•	Secondary biological purification. Most helminths will settle in the sludge resulting from secondary purification, together with 90-95% of bacteria and a significant percentage of viruses.The secondary effluent will thus be almost free of helminthes, but will still include infective concentrations of bacteria and viruses.
•	Tertiary treatment. The secondary effluent will probably contain at least 20 mg/liters suspended organic matter, which is too high for efficient chlorine disinfection. It should therefore be subjected to a tertiary treatment, such as lagooning. If no space is available for creating a lagoon, rapid sand filtration may be substituted to produce a tertiary effluent with a much reduced content of suspended organic matter(<10 mg/liter).
•	Chlorine disinfection: To achieve pathogen concentrations comparable to those found in natural waters, the tertiary effluent would be subjected to chlorine disinfection to the breakpoint. This may be done with chlorine dioxide which is the most efficient, sodium hypochlorite, or chlorine gas. Another option is ultraviolet light disinfection.  Disinfection of the effluents is particularly important if they are discharged into coastal waters close to shellfish habitats, especially if local people are in the habit of eating raw shellfish.
(c)        Sludge treatment

        Anaerobic digestion is required  to ensure thermal elimination of most pathogens from the sludge generated by sewage treatment plant. Alternatively, it may be dried in natural drying beds and then incinerated together with solid infectious bio-medical waste. On-site treatment of biomedical sewage will produce a sludge that contains high concentrations of helminthes and other pathogens.

(d)	Reuse of wastewater and sludge in agriculture and aquaculture

        If the treated wastewater is to be used for unrestricted irrigation then it should contain no more than one helminthes egg per liter and no more than 1000 fecal coli forms per 100 ml. It is essential that the treated sludge contains no more than one helminthes egg per kilogram and no more than 1000 fecal coli forms per 100 g. The sludge should be applied to fields in trenches and then covered with soil.               

(e)	Options for establishments that apply minimal waste management              
              procedures 

        A lagooning system is the minimal requirement for treatment of wastewater in a region or an individual health-care establishment that cannot afford sewage treatment plants. The system should comprise two successive lagoons to achieve an acceptable level of purification of biomedical sewage. Lagooning may be followed by infiltration of the effluent into the land benefiting from the filtering capacity of the soil. There is no safe solution for the disposal of sewage from a biomedical waste generator which cannot afford a compact sewage treatment plant and that has no space available to build a lagooning system:

2	      Minimal safety requirements

       For biomedical waste management agencies that apply minimal programmes and are unable to afford any sewage treatment the following measures should be implemented to minimize health risks: 
•	Patients with enteric diseases should be isolated in wards where their excreta can be collected in buckets for chemical disinfection.This is of utmost importance for example in case of cholera outbreaks and strong disinfectants are needed.
•	No chemicals or pharmaceuticals should be discharged into the sewer.
•	Sludge from hospital cesspools should be dehydrated on natural drying beds and disinfected chemically (e.g. with sodium hypochlorite, chlorine gas or preferably chlorine dioxide).
•	Sewage from biomedical waste should never be used for agricultural or aqua cultural purposes.
•	Biomedical  sewage should not be discharged into natural water bodies that are used to irrigate fruit or vegetable crops, to produce drinking water or for recreational purposes.
•	Small-scale rural hea1th-care establishments that apply minimal waste management programmes may discharge their wastewater to the environment. An acceptable solution would be natural filtration of the sewage through porous soils, but this must take place outside the catchment area of aquifers used to produce drinking water or to supply to the health-care establishment

3	     Sanitation 

         In many health-care establishments in developing countries, patients have no access to sanitation facilities. Disposal of excreta in the environment creates a high direct or indirect risk of infection to other people. Human excreta are the principal vehicle for the transmission and spread of a wide range of communicable diseases, and excreta from hospital patients may be expected to contain far higher concentrations of pathogens and therefore to be far more infectious than excreta from households. This underlines the prime importance of providing access to adequate sanitation in every health-care establishment and of handling this issue with special care. The fecal and  oral transmission route and other routes such as penetration of the skin must be interrupted to prevent continuous infection and reinfection of the population. The health-care establishment should ideally be connected to a sewerage system. Where there are no sewerage systems, technically sound on-site sanitation should be provided

2.10      Health & Safety Practices and Training of Workers

        For the continuous monitoring of worker’s health and safety, to ensure correct handling, provisions should be included by Bio-medical waste management policies or plans.The production, segregation, transportation, treatment and disposal of bio-medical waste involve the handling of potentially hazardous material. Protection against personal injury is therefore essential for all  workers who are at risk. The individuals responsible for management of bio-medical waste should ensure that all risks are identified and that suitable protection from those risks is provided.	

(1 )       Management practices 

        Many of the management practices recommended contribute to a reduction in risk for personnel who handle bio-medical waste. These are summarized as follows:
•	Waste segregation : careful separation of different types of waste into different and  distinct containers or bags defines the risk linked to each waste package.
•	Appropriate packaging: prevents spillage of waste and protects workers from contact with waste.
•	Waste identification (through distinct packaging and labeling): allows for easy recognition of the class of waste and of its source.
•	Appropriate waste storage: limits the access to authorized individuals only, protects against infestation by insects and rodents, and prevents contamination of surrounding areas.
•	Appropriate transportation: reduces risks of workers being exposed to waste.

(2)	Special precautions for clearing up spillages of potentially hazardous    
        substances

         For clearing up spillages of body fluids or other potentially hazardous substances, particularly if there is any risk of splashing, eye protectors and masks should be worn, in addition to gloves and overall respirators (gas masks) are also needed if an activity is particularly dangerous, for example if it involves toxic dusts, the clearance of incinerator residues, or the cleaning of contaminated equipment. Residues should be recovered as completely as possible using hand tools (e.g. a shovel), and then packed safely. It is especially important to cover spilled droplets of metallic mercury. If a leakage or spillage involves infectious material, the floor should be cleaned and disinfected after most of the waste has been recovered.

(3)       Response to injury exposure

        A programme of response should be established that prescribes the actions to be taken in the event of injury or exposure to a hazardous substance. All staff who handles bio-medical waste should be trained to deal with injuries and exposures. The programme should include the following elements:
•	Immediate first-aid measures, such as cleansing of wounds and skin, and irritation (splashing) of eyes with clean water.
•	An immediate report of the incident to a designated responsible person.
•	Retention, if possible, of the item involved in the incident details of its source for identification of possible infection.
•	Additional medical attention in an accident and emergency or occupational health department, as soon as possible.
•	Medical surveillance.
•	Blood or other tests if indicated.
•	Recording of the incident.
•	Investigation of the incident and identification and implementation of remedial action to prevent similar incidents in the future.
•	In case of a needle stick injury, bleeding of the wound should be encouraged and the areas should be washed under clean running water. The remaining elements of the accident response plan should then be followed.
•	The purpose of incident reporting should not be seen as punitive. Active support by managers should encourage prompt and accurate reporting.