Waste Management
A lot of things are used everyday in the hospital and then discarded. Care should be taken to see that the items are not strewn about everywhere, but are thrown into the dustbins. Dustbins should be provided in all areas of the hospital, and should be emptied daily, and in some areas where the waste generation is more the dustbins should be cleared twice a day. If decaying matter is not disposed of immediately, it emits a bad odour, and generates disease causing germs. This will affect the environment and our health. Hence it is very important to ensure that waste in a hospital is cleared and disposed daily. It is also important to ensure that the waste bins are washed daily and disinfected with dettol ( any disinfectant) and then put out to dry in direct sunlight.
In this lesson we shall study the importance of a good waste management system.
What is waste management?
The process of collecting, transporting, processing and disposing of waste is known as waste management. Nowadays waste management has gone one step ahead. It not only deals with planning of disposal but also attempts to see how we can reuse or recycle certain materials from the waste.
The waste from health care facilities is categorised into 2 main categories
General solid waste
This is the majority of all waste found in health care facilities and is similar to waste generated in other places. This includes:
-Paper
-Polythene
-Food waste
-Kitchen Waste
-Garden Waste
Bio medical waste
This is waste that is generated during diagnosis, treatment, and immunisation of humans or animals or during research activity. By implication, solid waste other than cotton, dressing, linen etc. which are contaminated with blood are considered as municipal waste, unless they come in contact with other bio medical waste. Bio medical waste includes:
-Cotton
-Swabs
-Infectious plastics
-Plastics
-Glass
-Syringes
-Needles
-Blades
Of the above, the last 4 come into the category of “sharps”, as they can easily cut or get into the skin of the person handling the waste, causing immediate infection.
The general waste can be further classified into 2 groups:
Recyclable waste
This is waste that can be re-used, such as
-Cardboard
-Paper
-Plastic bottles, covers and cups
-Ropes and strings
-Rubber items
-Shoes & slippers
-Thermocol
-Wood
-Coconut shells
-Cloth pieces
-Dry batteries
-Glass bottles
-Leather items
-Metal
Bio - degradable items
These are items that easily decompose and mix into the soil.
-Dust
-Food waste
-Kitchen waste
-Garden waste
-Coal and ash
-Hair
-Insects and rodents
-Tea and coffee powder
-Egg
Impact of poor waste management systems On people
1.Infections: This is the most common health hazard associated with poor hospital waste management. Those exposed to this hazard are-
a)Patients attending the health care institution
b)People visiting the patients in the health care institution
c)Medical and paramedical persons who are providers of medical care
d)Sanitation staff involved in collection, segregation, transportation and final disposal of waste
e)Staff working in support services of the hospital
2.Physical injury: This occurs due to the improper handling of various biomedical wastes at various stages of waste management. Out of various categories of waste, the sharps are the most prone
to cause physical injury, especially when intermixed with other waste
3.Chemical injury: This results from hazardous, toxic, corrosive, flammable, reactive and genotoxic wastes which can produce burns on accidental exposure, or cause toxicity to cells
4.Radiation injury: This occurs due to exposure to various forms of radioactive waste such as that from the chemotherapy and X-ray rooms
On environment
1.Water pollution: Measures should be taken to reduce the quantity and strength of incompatible pollutants in wastewater flow. If not connected to municipal wastewater treatment plant, an on- site treatment should be started. Sludge from such a plant should be managed with the same precautions as for municipal waste sludge ie. it should not be put on food crops unless treated properly. For chemicals, which are a potential source of pollution, an on-site chemical waste survey is a pre-requisite to the development of an effective waste management system. Waste chemicals, as far as possible should be recycled, and more hazardous chemicals should be substituted wherever possible with less hazardous chemicals. Use of disinfectants should be limited and alternatives used wherever possible
2.Air pollution: Most of the air pollution results from incineration. It should be ensured that incinerators for health care institutions be designed specifically for that purpose and must comply with the accepted norms of emission. Fume hoods, which are another outlet for air pollution should be fitted with filters
3.Soil pollution: General waste along with properly treated infectious waste can safely be disposed of in a specialised landfill. Properly operated incinerators produce sterile ash, which can safely be put in a specialised landfill
Generation and segregation of waste
Generation of Waste refers to activities and procedures, which result in the production of waste. In a hospital scenario generation of bio-medical waste is done at all levels and in all areas, starting from the highly trained specialists to the class IV sanitation staff. It is the first step in hospital waste management.
Source of waste refers to those areas or sites where wastes are generated.
Segregation of waste is defined as separation of different types of wastes by sorting.
It is the most important prerequisite in the entire process of waste management as it allows special attention to be given to the relatively small quantities of infectious and hazardous waste thereby reducing the risk and the cost of handling and disposal. Segregation of waste is the key to the entire process of scientific waste management, as proper sorting into different categories will entail right treatment and disposal. Segregation of waste should be done at source, and hence becomes the responsibility of the generators of waste, viz. doctors, nurses and paramedics. Sensitising the generators of waste to properly segregate the waste at source is the key to successful implementation of scientific waste management.It is important to put the waste in respective colour bin which is accepted by the management.
Collection, storage and transportation of waste
Collection of hospital waste is the process, which is done after segregation, and in a way, both can be considered as being complementary to each other.
Several guidelines have been suggested for categorisation of hospital wastes enunciated by various authorities. One of these is the colour coded classification for developing countries by WHO:
| S.No. | Category of waste | Recommended colour code |
| 1 . | General Non- hazardous waste | Black |
| 2 . | Sharps (infected or not) | Yellow |
| 3 . | Infected waste (not containing sharps) | Yellow |
| 4 . | Chemical and Red Pharmaceutical waste (other than cytotoxic drugs, radioactive wastes, high pressure containers | Red |
| 5 . | Clinical wastes that need autoclaving | Blue |
Storage is the duration of time the wastes are kept in the areas of generation and transit, till the point of disposal. One should be very careful about storage, as unless the waste is securely stored, unscrupulous elements and rag pickers may gain access to the waste and cause problems. Under the provisions of Biomedical Wastes (Management and Handling) Rules, 1998, the following section pertains to the storage of waste:
Authorised persons handling biomedical wastes shall ensure that:
1.No untreated biomedical waste shall be stored beyond a period of 48 hours
2.If, for any reason it becomes necessary to store waste beyond such period, the authorized person must take permission of the prescribed authority and take measures to ensure that the waste does not affect human health and the environment
No waste shall be stored where it is generated beyond a period of 48 hrs.
Characteristics of waste storage containers
Containers for interim waste storage must have the following characteristics:
1.Made up of hard plastics / metal which should be sturdy and leak proof
2.The size of the containers will depend upon the quantity of waste generated
3.Should have a secure lid which can be shut after the waste is collected. It should not allow insects and animals to go inside
4.Should be puncture proof, reusable, colour coded, labeled and not easily destroyed by rodents and other animals
5.The inner surface should be smooth and rounded without any sharp edges which can tear the plastic bags kept inside
It is preferable to have three sizes – for collection, storage and transportation
Plastic bags used for waste collection, storage and transportation
1.Should be large enough to accommodate all the waste of that particular category. It should completely line the container and a portion of it should be outside
2.Should be sturdy enough to withstand the weight of the load of waste without tearing or giving way
3.Should be leak proof and water proof, without any weak areas or tears
4.Should be colour coded. Labeled and marked clearly with labels
In case the bags are to be incinerated they should be made up of non-chlorinated plastics
Waste collection area / centre should have the following characteristics
1.Should be an area specifically marked for collection and storage of waste, pending treatment and final disposal
2.Should be covered and protected from all sides against humans and animals
3.There should be a proper facility for locking of the area to prevent tampering by rag pickers. The key should be kept with a responsible person at all times
4.There should be a clear warning sign with symbols
5.Location should be away from public places and food preparation areas
6.Construction should be robust with drainage system, lights and ventilation
Transportation
Waste disposal is a multiphase activity, in which the different stages (ie. generation, segregation, collection, interim storage, transportation, treatment and final disposal) are highly interdependent, both technically and organisationally. In this entire spectrum of activities, collection and transportation form a vital link between the point of generation and final disposal.
Types of transportation
Internal
This refers to the transportation of waste from the point of generation and storage in the wards to a point outside the building premises, where it is kept, pending the transport to the actual site of disposal.
External
This refers to the transportation of waste from the central collection point outside the building to the site of final disposal.
Vehicles for transportation
Internal transportation
1.Push cart - An open push cart designed so that one or two bins/containers of waste can be moved from rooms to the garbage trolley parked outside the ward
2.Waste trolley - A large trolley made of iron/ stainless steel with 4 revolving castors and of
sturdy construction. It should be covered so that insects, flies, etc. do not have access inside to it
3.Wheel barrow - Can be used for small amount of general/non-hazardous waste
External transportation
1.Cycle rickshaw - can be used if the site of final disposal is close to the hospital. It should be covered on all sides and can be divided into 2 compartments, for infectious and non-infectious waste
2.Van / lorry - It should be earmarked for waste transportation with the label ‘Bio medical Waste” on both sides and at the back. It should be fully covered and lined internally with aluminum or metal to give it a smooth impervious finish. It should have rounded corners without edges or angles for effective cleaning and disinfection. The driver’s cabin should be fully separated from the bulk head, and the load compartment should be securely locked during transit. If the journey to the site of final disposal is long, roof vents need to be provided for ventilation
Final disposal
Disposal means burial, discharge, deposit, dumping, land-filling or placing on land, of any biomedical waste.
Disposal of general/non-hazardous solid waste
Depending upon the quantity of general non- hazardous wastes generated in the hospital the following are the options available for disposal.
For small quantities of wastes
1.Landfill: This is the most satisfactory method of garbage disposal where suitable land is available. However, the site of landfill has to be chosen with utmost care and the following factors regarding construction should be kept in mind: - It should be avoided near sources of water
-The site should be securely fenced and should have a gate away from public view with signboard stating “Landfill site”
-Covered with at least 0.5m of suitable cover material
Landfill is done by any of the following methods:
-Trench Method – A long trench 2-3m deep and 3-10 m wide depending upon local conditions is made.The treated waste is ideally compacted, filled up to 2m and covered with excavated earth
-Ramp Method - This is well suited where the terrain is moderately sloping, and excavation is done to secure the covering material
-Area Method -This method is used for terrain land depressions, disused quarries and clay pits. The treated waste is deposited, packed and consolidated in uniform layers up to 2- 2.5 m deep. Each layer is sealed on its exposed surface with a mud cover at least 12” thick to prevent infestation of flies, rodents etc
After the waste has been buried, chemical, bacteriological and physical changes occur and the temperature goes up to 600 C within 7 days hastening the decomposition process. Within 4-6 months complete decomposition of matter occurs into an innocuous mass. The potential use of filled land includes improvement of eroded areas, marshes and other marginal land.
2.Pit Burial: This is suitable for small camps or institutions, where in a small pit of size 2m by 2m waste is put with 10cm soil between each layer of waste. When the level is full, it is closed with a thick layer of soil. It is also fenced with secure gate for entry and exit. Contents get decomposed within 4-6months
3.Composting: This is a method of combined disposal of refuse and night soil. It is a process whereby organic matter breaks down under bacterial action resulting in the formation of relatively stable humus like material called
compost which has considerable manorial value for soil as it contains nitrates and phosphates. The temperature achieved over a period of days destroys the eggs and larvae of flies and other insects.
Vermiculture: In this process, the biodegradable wastes from the kitchen, houses and the cafeteria are converted into manure with the help of earthworms. Organic waste is kept in wooden boxes or earthen ditches with small amount of waste at the bottom. A small bunch of earthworms are placed in each part and covered with organic matter. This is sprinkled with water, and in due course gets converted into manure
For large quantities of waste
1.NADEP Composting: General refuse/waste can be converted into rich, soft, good smelling compost by using this simple, economical and non-polluting technology
2.Pelletisation Technology: This process converts biodegradable wastes into “fuel pellets” by treatment with heat, humidity, and pressure by machine designed for this purpose.The fuel thus developed is cheaper, has less smoke emission but lasts longer
3.Biopress Methods: This turns garbage into incinerable matter and produces methane gas. Methane is produced naturally in any landfill through decomposition of organic matter, over a period of 20-30years.It contains roughly 50% methane and 50% carbon dioxide. The recoverable gas is about 50-80% of the total gas which can be used for:
-Generation of electricity in an internal combustion engine or gas turbine
-Directly as a boiler fuel
-Compressed for vehicle fuel or upgraded to pipeline gas
4.Gasification technology (biogas from organic waste): Energy derived from anaerobic digestion of organic waste involves the production of biogas from organic waste. The technology involves the separation of wastes at source or mechanically prior to digestion and comprises the following steps: (i) pre-treatment (ii) digestion (iii) post treatment of waste. This process is eco friendly and recovers 100% methane, reduces odour, produces electricity and displaces carbon dioxide. It is a traditional source of energy and forms a suitable by-product, viz. compost which is an excellent manure
Disposal of human anatomical, blood and body fluids
The preferred treatment for this is incineration. After incineration, the ash can be sent for specialized landfills, as it is sterile.
Disposal of sharps
Although sharps comprise of a relatively small proportion of the total hazardous waste generated in any hospital, they have the maximum propensity and potential for causing needle “stick” injuries and hence can cause infection. It has been proved beyond doubt that the category of waste that needs maximum precaution and care is sharps. Sharps are stored in areas or points of generation in puncture-proof containers. Before storing them, the needles, which comprise the majority of sharps, can be destroyed by needle destroyers or by using syringe melting and disposal systems.
Disposal of microbiological and technological waste
This is disposed using any of the technological options such as autoclaving, microwaving, hydroclaving, or incineration.
Disposal of pharmaceutical and infectious solid waste
This can be incinerated and the ash can be disposed of in landfills.
Disposal of chemical waste
Non-hazardous chemical waste can be disposed of using the same method as general wastes. The waste that can be recycled should be packed, labeled properly and stored for recycling. Hazardous chemical waste should be recycled if possible or treated and disposed of in sewers after dilution (liquids) or incineration (solids). The ash is disposed of in landfills.
Disposal of radio active wastes
This should be done as per the guidelines laid down by BARC, India. These wastes can be disposed of in the normal channels under strict supervision, after their radioactivity is neutralised.
Solids should be stored in appropriate containers like plastic bags or large cans under strict security and thereafter disposed of as ordinary waste after removal of all radioactive labels and warning signs. Liquid
and gases, which are generally low-level radioactive wastes, should be diluted properly and disposed of in the sewers or released in the open atmosphere.
Disposal of pressurised container
These should be disposed of with general waste, in specialised landfills.
For a demonstration on waste management, please watch the video of the CD.
Student exercise
Answer the following
1.What is waste management?
2.Why is it important to have a good waste management system?
3.What are the different types of waste generated in an eye hospital?
4.What are the wastes generated in a multi speciality hospital?
5.What are the measures the Housekeeping Department can take to reduce the generation of waste?
