Guidelines on Biosafety

[[p.1]]
Guidelines on Biosafety
"The aim today should be to reduceHal and ensure that no one acquires HIV infection from
the hospital by strictly observing the,precautions recommended for handling blood and body
fluids, precautions in relation to infections, skin piercing and invasive procedures effective use
of sterilisation and disinfection and disposal of infective wastes."
Dr. A.K. Mukherjee
Director General of Health Services
It is a universally accepted fact that blood and blood products has the potential to develop into a
health hazard either through transfusion or contact with abrased skin surface" open wound and passage
through body orifice if the unscreened blood/blood product is handled carelessly or without any
precautionary measure,
Historical review
That the diseases could be infectiousand communicablewas not unknownto theman even fourcenturies
ago asevidenced fromthe "Theoryof contagions" enunciatedbyFracostorius(1483to 1553). Hedescribes
three different contagion.
(a) Infects by direct contact
(b) Also infects directly but in addition leaves fomes
(c) Those which infects from a distance.
Following Fracostorius,vasalius (1514-1564)and AmbroisePare (1517 to 1590)did a lot in revival
of surgery. The period following 1500AD can be called renissance period of medical science.
The new era of medical science is saidto be between 17 to 18th century discovery of circulation,
microscope, stethoscopeandpercussionasa methodinclinicalmedicineetc.andsomanyotherdiscoveries
were made. It was during this period, the Lady with the Lamp - Florence Nightingale (18(i3) gave
mankind the preliminary understanding that infections can be acquired in hospitals or in such type of
settings. The antisepticera started with discovery of carbolic acid and its clinicaluse by JosephLister in
1865. The year 1870 marked the beginning of asceptic era discovery of germ theory by Louis Pasteur.
370

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Guidelines of Biosafety
371
The otherexponent in this area was IgnazSemmelweiss who conducted someexperiments and studies
related to HAl, he was contemporary to Louis Pasteur.
Hospital acquired infection
("~t!\l)
Infections inhospital canbeacquired through auto-infections, cross-infectionandenvironmental infection.
Theepidemological triadplaysadefinitive roleinacquisition andspreadofinfection-aerial, oral,parenteral
and contact. HAl can also be contacted through some of hospital procedures like surgery, delivery,
invasive and non-invasive investigations, transfusion of blood and infusion of fluid and laboratory
procedures. The last two gained more importance after discovery of hepatitis and AIDS. It has been
observed through experience that an effective prevention of HAl can be achieved by interrupting the
transmission :
(a) Screening
(b) Isolation
(c) Erectonof barrier
(d) Controlling the exit point or route of transmission
(e) Immunisation of susceptible person
(t) Sterilisation etc.
The personnel working in laboratory or any health care worker concerned with laboratory may
acquire infection through handling of samples (blood and body fluids) tissues, bronchial washings,
swabs.Insofar, the bloodbankand its laboratory, the sourceof infection couldbe blood,bloodproducts
and body fluids. Anyone described may contain biohazards HbsAg, mv, HC~
Trepanoma etc., and a
health care worker (HCW) may acquire these biohazards during. handling of samples, processing of
blood or product and/or disposal of discarded blood in blood bank, therefore, the source materials
considered potentially biohazardous are to becarefully handledand requiresproperattention to prevent'
spread of possible infection to HCW and/or any other person involved in handling of blood-sample/
blood/blood product. Theprocedures adopted orrecommended toensureprotection andsafetyof workers
areknown as biosafe procedures. On principle, these are to be practicedfor biosafety (Table 13.1)of
Hew and concerned individuals. A brief discussion of methodology, procedure and practicebased on
principlesrecommended by national and international bodiesare summarised.
. Table,: 13.1.
Biosafety
I
Personnel
·care and
hygiene
I
Interruption
of transmission
or routes
I
Handling
transfer and
shipment
I
Protective
barrier
I
Biological
(immunisation)
I
Heat
I
Decimation
or
inactivation
I
Chemical
I
Disinfection
I
Radiation
I
I
Gas
U.V. light

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372
Blood Banking and Transfusion
Commonly employed methodology are based on principle of :
(i) Interruption of transmission and/or route of transmission.
(ii) Decimation or inactivation of bacteria, virus, spirochaete through physical, chemical and
biological means.
A health care worker can acquire infection due to exposure in course of his work from source
material containing biohazards (bacteria, virus spirochaete) through possible routes of infection like
skin abrasions, puncture and body orifices, the aerial route in blood bank laboratory is rarest.
Personal care and hygiene
(a) Wash hands before leaving lavatory and laboratory, before eating, drinking and smoking; after
you remove your handgloves. Washing of hands are done with soap and water. Repeated use of
spirit or mild detergents as an extra safety measure is to beavoided because this, in some cases
may give rise to local allergy.
(b) Trimming of nails properly and regularly.
(c) No eating, drinking and smoking inside the laboratory or processing area (component separation,
storage area, hot room etc.).
(d) No pipetting by mouth.
(e) Donot ever work in blood/bank with any open wound, abrasion of skin etc.
(f) Donot store any food, drinks etc..in blood bank refrigerators, walk-in-coolers or anywhere with
blood and components etc.
(g) Avoid putting fingers or pen like objects in the mouth.
(h) Avoid crowding and loitering by children within .laboratory and processing area of blood bank.
(i) Avoid direct contact of samples, component and blood with skin and finger; cover the tube's
mouth with paraffin or rubber stopper the mouth of sample container.
G) Any spill of samples, component or blood on table top and sinks must be immediately attended
with swabs soaked in hypochlorite solution.
(k) In case there is any direct contact of blood, blood product and samples with skin or finger, wash
hands immediately with soap and water twice or thrice, running water from tap is preferred.
(1) Periodic check up of health of HeW to ensure that he/she has not acquired any disease or TID
and take necessary. treatment, if the condition warrants and never to attend laboratorylblood
bank works unless cleared by competent medical authority.
Handling, transfer and shipment
It includes blood/sample collection, specimen transfer and manipulation, cleaning and maintenance,
shipment and waste disposal. The health care workers who are directly connected with these works are
phlebotomist/doctor, laboratory personnel, transport workers including postal workers (if specimen are
transported by postal means), the support staff and the launderers. The improper handling of the source
.material by the HeW and other staffs, thus posses a grave risk of HAL A guideline in this regard will be
appropriate to avert risk of HAl.
(a) Any material or any place, where the specimens are collected, stored or processed is to be
labelled as "Biohazard" (Fig. 13.1) or area is marked "Restricted Entry" (Fig. 13.2 and 13.3),

[[p.4]]
Fig. 13.1. Intemational sign biohazard.
Guidelines of Biosafety
373
put international insignia of Biohazard in front of
routine laboratory donor, discard blood store or
specimen store, HIV laboratory, HbsAg laboratory,
VDRL lab. The blood container or soiled article
container should be labelled as biohazard.
(b) Ample space in the laboratory and no over crowding
in working area, impervious bench tops or marbel tops
.of laboratory working table, properly and adequately
lighted room, sturdy furnitures, self closing door fitted
with vision panel, airconditioned and well ventilated
laboratory/working area.
(c) Frequent cleaning oflaboratory and wash basins with
detergent solution.
(d) Continuous water supply.
(e) Isolated place within the laboratory or a disposable container where the wastes are deposited.
(f) Walls ceiling and floor made of washable, heat and chemical resistant material. Floors to be
kept dry and not slippery.
(g) Blood tested and meant for issue to be kept in a separate blood bank refrigerator and riotmixed
up with untested blood or specimens meant for storage.
(h) Cloak room outside laboratory for keeping personal.belongings and outer garments etc.
(i) Disposable syringe and/or needle i~ to be spoiled by heating in flame, then drop in a container
having bleaching powder solution. Alternatively, they can be incinerated in incinerator. Better
not to reuse, though, it is said that boiling in water continuously for 20 to 30 minutes may
disinfect them.
Fig. 13.2. Intemational sign prohibition.
-:
"'"X"j(~
...; .:
"J.....-~'t..
~
D .....~ ... ~
.... :
-""
;~.
<,;
'':~:;;
~~~,
.."~-,,
~~~.;~:}'/;~\;"'~'<'.-'~'</
.::~.
~~
~It
-.
"l;~
...";.
...:~
~t .. ,'t:({ ~1./
~
'" ~~*.:",~
,
,
{,'
~
~
~
~~"
~';··t~"'\·
Fig. 13.3. Intemational sign mandatory.

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374
Blood Banking and Transfusion
G) Soiled linens must be handled with gloved hands, isolate them in a plastic bag immediately and
tie the bag, label biohazard and sent to laundry where launderer handles them with gloved hand
and boil the soiled linen with detergents in hot water (minimum temperature not below n°C)
for 25 to 30 minutes. Bleaching powder can be used as detergent.
(k) For blood spills soak with I% bleaching powder for not less than half an hour, thereafter,
mopping and soap water cleaning.
(1) House keeping does not require any special method except for frequent washing with soap and
water and take necessary care for spillage, use gloves while cleaning.
(m) Soiled instruments are washed first and then put for 30 to 40 minutes in a solution of 2%
glutaraldehyde.
(n) The specimens must not be transported in open mouthed container or open tray. All the blood
specimen properly sealed in plastic/glass container, no blood in the outer wall of container. The
primary container is then put into another metal or plastic container properly sealed and see that
no leak can occur from the secondary container. If the blood specimen is known or reactive
specimen of HIVlHbsAglVDRllHCV, it is labelled as "Biohazard" before transport. If it is to
be sent through post (shipment), proper precautionary measure has to betaken. Ifwithin hospital,
the plastic secondary containers may be used even when specimen are despatched from ward to
blood bank and vice versa.
(0) All wastes collected in a primary container, mostly plastic bags are tied at its mouth put into a
secondary containerlabelled as Biohazard and then sent for incineration. The known and reactive
blood bags ofHbsAg, HIV and HCV are first autoclaved and sent for fmal disposal as described
above. Dumping of wastes and blood bags are discouraged and should never be restored to for
the purpose of waste disposal. Observe official formalities of the wastes and blood bags before
sending it for incineration, Fill up the forms with number of blood bags total and serial number
mentioned for ~
HbsAg and HCV positive bag, the amount and contents present in other
wastes in disposal bags are all recorded before sending them to incineration department, obtained
receipt for the items despatched/deposited for incineration from a responsible official of
incineration department.
Protective barrier
Every HCW working within blood bank
premises must wearor use materials/devices that
can be effectively act as a protector and prevents
direct contact of blood with workers person. The
attire and devices are apron, gloves, eye shield,
safety glass in front of workers face mask, head
cover and rubber slipper. Out of all these, the
gloves and apron (knee length) is must for every
HCW.
Hand gloves (Fig. 13.4) used must be of
proper size and fitting so that it doesnot cause
any disturbance in working. Gloves are made
Fig. 13.4. Handgloves protective barrier.

[[p.6]]
Guidelines of Biosafety
375
up of latex or PVC, material and can be reused; the disposable gloves are made up of plastic material.
Latex gloves has natural porosity may be due to'silicon etc. embedded in and the porosity may range
between 3 to 15urn whereasHBV andmv is respectively 0.042 urn and O.10'Jlrn diameter.Further, the
use ~f detergentmaycause "Wicking",so hand gloves to be usedmust bear lSI mark or check the gloves
for internal quality control, and if more than 1.5% of gloves are found defective, that batch is rejected.
Checking of gloves can'be done by filling each glove with 325 ± 25 ml of water at RT. The gloves after
filling is twisted 360°and is placed over a rackfor two minutes afterwhich observe for leakageby visual
or tactile means. However) uptill now, the latex gloves tested for seepage possibility of virus (HIV,
HBV) after prolonged contact with virus.culture, failed to detect any leakage of virus, but since the
theoretical possibility cannot,be excluded, we must be cautious in using gloves, at least, it should be
checked by air insufflationor any visible perforation,crack etc. before use. Single use nonsterilegloves
are recommended for laboratory use but if, the gloves are to be reused the gloves are reprocessed as
follows:
(i) After the working is over, rinse the gloved hands,with hypochlorite solution adequately and
thoroughly.
(ii) Wash gloved hands with soap and in running water and then rinse in.clean water, procedure
may be repeated twice.
(iii) Remove the gloves and hang them by cuff for drying.
(iv) Check each gloves by air insufflation.
(v) Sterilisethe gloves.
(vi) Spray with talc powder,
If gloves are not to be reused.jhen throw them in waste container for final disposal. The degloved
hands are washed thoroughly with soap, in running water, and then immerse the hand in antiseptic
solution, rinse in clear water before you go out of laboratory.
Precautionary measure to be undertakenif the gloves get needle prick of perforatedduring working;
to facilitate easy entry of fingers and hand spray talc powder over the hand and finger.
Aprons or laboratorycoat are useful to protect the person from splashedbloodlbloodproductetc. or
unnoticed spilling of contaminated: blood/blood product similarly eyes and'nose can be protected from
splashed bloodlblood product by'using eye shield and face mask. Eye shield, face mask, head gear also
protects a person from impacting objects, closed type slippers and socks to be used to protect the foot
and legs, preferably donot bring.in the shoes that are used outside,
Decimation or inactivation" of' ~frus,.
bacteria
This can be done.by either raising the body resistancethrough immunisationor by directly tacklingthem
through,physical and chemical means.
lmmutusetion
A blood bank .:HCW can be immunised against HBY which is more infectious than HIV. But regarding
HCV, NANB and mv vaccination are yet to be discovered. We can thus protect a blood bank HeW
from HBV through a vaccination protocol for HBV.

[[p.7]]
Fig. 13.5. Disinfection of instrument.
376
Blood Banking and Transfusion
Chemical disinfection
The disinfectant in common use 1.0% hypochlorite solution, i.e., 10,000 PPM. This solution is by
dissolving 10 gm of hypochlorite in a litre of 0.5% anionic or non-ionic detergent and is said to be the
best general purpose disinfectant, if kept in contact for half an hour at least. The sodium hypochlorite is
useful particularly in case of spillage where the solution is poured around spill area covered with some
absorbent material for 30 minutes. After that the absorbent material is disposed offinto the waste container.
The spilled area again mopped with hypochlorite solution soaked in absorbent material which is again
disposed off in the waste container. The working table and wash basin etc. are cleanedwith hypochlorite
solution or gloved hands are also cleaned with hypochlorite solution. This solution is stored in a black
container that doesnot permit access to light.
Other chemical disinfectant used in high label disinfection are, formaldehyde/glutaraldehyde, 5%
carbolic acid, alcohol (ethylalcohol 70%, methyl alcohol 70%), betadine 2.5% chloramine 20 g/litre
is said to be more stable than sodium hypochlorite, dettol (chloroxylenol 4% to 10%), savlon
(chlorhexidine with cetrimide), ethyline oxide gas.
For general purpose disi nfection, the 0.1 % and 1.0%
sodium hypochlorite is commonly used respectively for clean
contamination
and
dirty
contami nation
(grossly
contaminated). Also, it is said to be quiet effective against
mv, if contact is maintained for thirty to forty minutes with
1.0% hypochlorite solution (Fig. 13.5).
Dettol and savlon are used for general purpose cleaning
of hands etc. Carbolic acid (Phenol) for cleaning of floors
etc.
No syringe or needle should ever be disinfected with
chemical disinfectant.
Physical agents employed for disinfection are heat alone,
heat with controlled pressure, gas, radiation and ultraviolet
light.
Heat
Dry heat or moist heat are used for high level disinfection.
Heat with controlled pressure are used in autoclave steam under pressure 15 to 20 PSI (lbs/sq/in)
equivalent to 121°C for twenty to thirty minutes is commonly employed for sterilisation of instruments,
liquids in container, mattress, linen, gown, coat.
Simple boiling in water for 30 minutes continuously can also sterilise the materials and equipments.
Gas
Ethyline oxide gas is employed to sterilise the plastic disposables, transfusion sets, syringe, needle,
recommended strength of ethyline oxide is 450-800 mg/litre irradiation-ionising radiation are used to
sterilise material that can be affected by temperature/heat viz. plastic disposable and transfusion sets.
Ultraviolet light has been successfully employed in inactivating the poliovirus. Beta propiolactone
with IN light was found effective against HBV and it was also demonstrated that HIV could be inactivated
by UV light in presence of photosensitising gent like psoralen.

[[p.8]]
Guidelines of Biosafety
3n
The methods described above are sufficient to disinfect or sterilise the contaminated or infected
materials from bacteria and virus even sporebearing bacteriabut the mv reported to beadelicate virus
was found resistant to irradiation by gamma ray and 'X-ray, UV light alone could not inactivate mv,
neither dry cleaning could eradicate the HIV.The HIV which is very sensitive to heat required continuous
.heat treatment for 20 hours at 60°C for getting inactivated. The transmission of HIV from blood and
body fluids, infection and skin piercing".though rarely, reported due to biosafe procedure in practice
(already described), we cannot overlook the possibility of accidental transmission through improper
handling of source material. A high level disinfection, is thus, the,only answer to prevent accidental
onslaught by HIV.
Sterilisation and high level disinfection
By this method almost all .microbes are destroyed except some spore bearing bacteria that requires
special treatment to get inactivated. HIV and HBV too are destroyed/inactivated by high level disinfection.
Commonly practiced method is application of Heat viz. dry heat, moist heat, simple boiling.
Dry heat can be applied by hot air oven, recommended temperaturerange is 160°C to 180°C for one
to two hours commonly used for sterilising glasswares viz., all glass syringes, test tubes etc., other
materials and blunt instrument that can withstand the heat of 170°C. It is also used for sterilisation of
material that are impermeable by steam viz., wax, petroleum jelly, oils and powders. It is effective
against ~
HBV bacterias spore-bearing and non-spore bearing.
Moist heat
It can be applied by autoclaving and simple boiling. Autoclaving can be done at temperature above
100°C or below 100°C.
Fig.
13.6
~ Steam jacketed autoclave.
Above 10f7JC
steam under pressure under pressure 15 to 20 psi (lbs/sqr inch) for twenty five to thirty
minutes, this 15 lbs of steam under pressure with complete air discharge will correspond to 1210e. 15
psi is equivalent to one atmospheric pressure and
121°C in 1,5 to 20 minutes. Sterilisation can be
effected at this steam under pressure. A pressure
of 30 psi approximately equivalent to 140°C,
holding time of 3 to 5 minutes is used rarely in
some special cases. To apply this pressure,
simple autoclave or streamjacketed autoclave is
sufficient (Fig. 13.6). WHO and UNICEF in
collaboration has devised a modified pressure
cooker which.can also' achieve this level.
Below 10f7JC
This method is also known as LTSF or low
temperature steam formaldehyde. Here the
formaldehyde
vapours
are
used
at
subatmospheric pressure for effectively

[[p.9]]
378
Blood Banking and Transfusion
sterilising items that cannot withstand a temperature of 100°C. Operating condition are 75°C at sub-
atmospheric pressure in a holding time of 60 minutes to 65 minutes.
Simple boiling at 100°C for.20 to 30 minutes continuously can also achieve same level of disinfection
and can be used in places where facility for autoclaving doesnot exist. .
The heat application is used for sterilising all sharp instruments (needle, lancet. knife, surgical
blade, scalpel, scissors}, blunt instruments used during operation. Mattresses can also be sterilised in a
specially made big autoclave designed for this purpose blankets those which are not washable viz.,
woollen blankets can be sterilised by a~toclaving.
High level disinfection can also be achieved by chemical method but is said to be less reliable than
heat technique. The chemical agents described earlier are used for disinfection. The materials are kept
immersed in the solutions and keeping them in contact for not less than half an hour. Needles and
syringes are disapproved for sterilisation by chemical disinfection. Commonly used chemicals are sodium
hypochlorite 1% solution, formaldehyde 4%, glutaraldehyde 2%, 6% hydrogen peroxide etc.
Irradiation by gamma ray and ultraviolet ray is also used for high level disinfection for plastic
disposable or those materials which cannot withstand heat. But either of this are not suitablefor inactivating
HIV.
Similarly, filtration technique can also be used, but these are considered less reliable for virus and
some bacterias as well. Out of all filters in use, the membrane cellulose type of filter are found most
satisfactory.
For blood bank purpose, the autoclaving above 100°C, simple boiling where the autoclaves are not
available and chemical disinfections are considered more practical. For disposable plastic materials, the
gamma ray radiation is to be practiced.
Disposal of wastes/discards
The wastes/discards from blood bank can be highly infectious because they are mostly contaminated
with HCV, HIV, HBV overtly (known blood specimen/whole bloodlblood product reactive and positive
to mv and HBV) and/or covertly. So the disposal of
blood bank wastes/discards is to be done under proper
supervision and ensure their final disposal in a manner
that prevents the recycling of the materials so disposed.
The overt wastes are disinfected first and then disposed
off by incineration. The blood bank waste and discards
are to be disposed off by incineration only, the practice
of disposal by dumping of the blood bank wastes are to
be discouraged. The general wastes are first disposed
offin a leakproof, punctureproofprimarycontainer which
is then put into a secondary container made ofplastics or
metal which are properly tied or .sealed, and labelled
Biohazard. The necessary official formalities are
observed viz. filling up 'of documents etc., before
despatching them for incineration. The 'known cases
Rg. 13.7. Incinerator.

[[p.10]]
Guidelines of ,Biosafety
379
before being despatchedfor final disposal. Despatch materialsare carried to incineratorby support staff
who are fully protected by protective attire and gloves. The materials are deposited in the incinerator
department,whereincinerationiscarriedoutunder supervisionof responsibleofficer.Bloodbanksupport
staff obtains a receipt for items'deposited'fordisposal by incineration.These receipts are kept in file for
record.
Thespecimenobtainedfromwardandothersourcescaneitherbedisposedoffbypooling allspecimen
and mix with hypochloritesolution, incubated (or 30 minutes, then disposed off in a leakproofcontainer
for final disposal by incineration.Or the specimen can be carefully poured in a wash basin with running
tap water, the exit pipe opens into sewer where the,specimen gets diluted in running water flowing
through the sewer.
Soiled linenlblankets are either disposed off by incineration, if they are grossly contaminated with
known positive bloodlbody fluids. For clean contaminated linenlblankets, reuse may be' considered, if.
proper facility for decontamination are available.Decontamination can be done by sending the soiled
linen (clean contaminated) in a polythene packlbags of different colour and then mechanically wash
them with hot detergent solution in the washing 'machine' of the laundry and dry them in mechanical
drier.The cotton blanketscan be decontaminatedlike linen but the woollen blanketsare first exposed to
formaldehydevapouror theycan be·autoclaved. For decontaminationof mattressbig autoclavesspecially
meant for the purpose are employed. '
Housekeepingin bloodbankdoesnotrequireanyspecialdecontaminationmethodandthecommonly
used methods like cleaning'with soap, water and/or phenol is sufficient. Special care has only to be
taken for blood spills (already described) and deposit of all wastes in a leak proof, puncture proof
container,Routine check for microbialcontaminationof floor,bench-topsand autoclaves,other furniture
etc., are to be carried out and necessary measureforcombating infectionhas to beundertakenand rigidly
implemented as per recommendation. Continuous pur:e water supply for laboratory and blood bank is
necessary and cannot be compromised,
Laundry and linen has already been described. The hot detergentat a temperaturenot less than'72°C
for 25 to'30 minutes has to be employed for decontaminationof soiled linen. Toilet,urinal, bed pan are
not source for HIV spread and need not require any special care, the' routine cleaning is sufficient.
Sluice, excretions, bloodlbody fluids are poured down into running water and exit pipe is connected
with a sewer throughwhich wateris flowing.Wastecan and suctionjar are to be washedwith soap water
followed by chemicaldisinfectionin 1%·hypochlorite for 30 to 35 minutesor theycan also be autoclaved.
Furnitures are cleaned with soap and hot water periodically. Use of bleech is highly recommended for
the waste cans where the wastes are deposited.
Books recommended for further reading
1. Clinical Diagnosis and Managementby Laboratory Methods of Todd, Sanford, Davidshon. John Bernard
Henry, Second Indian Edition, 1989, A1!BS.
.
.
2. HospitalAcquiredInfections, Guidelinesfor Control; Padma ShreeDr. Sriniwas, Firstedition, 1992,Ministry
ofHealth and Family Welfare (DepartmentofHealth), Nirmal Bhawan; New Delhi.
3. Standard, for Blood Banks and Transfusion Services, H.M. Bhatia, Chhaya Gupta, Jolly, Koticha, Saran,
Verma, First edition, 1987, DGHS, MOR and Family Welfare, G01, Nirman Bhawan; New Delhi.

[[p.11]]
380
Blood Banking and Transfusion
Journals and articles
(a) Risk ofTransmission ofHNfrom Health CareProfessional to Patient, Correspondence Publishedin,Care
Calling, Vol. 4, No.4, Oct.-Dec., 1991, 4.
(b) Recommendationsfor Preventing Transmission ofHWandHBVtoPatients During Exposure Prone, Invasive
Procedure, CDCAIDS Weekly, Aug. 26,191, pp. 19-24, News itempublished in Care ~alling,
Vol. 4, No.4,
Oct.-Dec., 1991, 7.
(c) Gangakhedkat; R;R., Protective ValuesofGloves and Condoms inPrevention ofHlVInfection, CareCalling,
Vol. 4, No.4, Oct.-Dec., 1991, 18.
{d) Prodouz N. Krishnaand Fratantoni, C. Joseph, Inactivation ofVirus inBloodProduct, Transfusion Bulletin,
Vol. 5, lVO. 5, Jan. i988, 3-5.
(e) Pawri, Khorsed, StandardBiosafety Guidelines for BloodBanks, Transfusion Bulletin, Vol. 4, Number 3,
Oct.-Dec., 1991,6-11.