Department of Oral & Dental Pathology and Microbiology/Oral Medicine & Dental Radiology


Dept. data last updated on :08/04/2024


Safe Operating Procedure


This SOP provides general information on fire prevention, as well as detailed information regarding fire extinguisher classification, type, size, location, and use. Other EHS SOPs provide information regarding fire safety related to specific materials, such as flammable liquids, compressed gases, pyrophoric chemicals, etc.

Fire Prevention

o   Keep corridors, and exit areas clear of items that impede egress in an emergency (i.e., chairs, tables, boxes, equipment, etc).

• Properly store combustible items. Do not accumulate unnecessary cardboard boxes, chemicals, and paper products.

o   When stacking or storing items on shelves, the top of the items must be a minimum of 18” below sprinkler head deflectors.

ü  Properly store compressed gas cylinders.

ü  Purchase equipment that is approved by a testing organization, .

ü  Keep electrical equipment, cords, and plugs in good condition.

ü  Arrange for an authorized factory representative or electrician to replace electrical cords or plugs that are in poor condition (i.e., frayed, cracked insulation, loose prongs, etc.).

ü  Do not overload electrical outlets.

ü  Report loose electrical wall receptacles, missing outlet faceplates, and exposed wires to the Building Maintenance Reporter (BMR)/ Electricity department of university.

ü  Disconnect electrical equipment that could possibly overheat when unattended.

ü  Keep fire extinguishers charged, stored in their designated location, and ensure annual inspection.

ü  When using a space heater, allow a minimum of three (3) feet between the heater and combustible materials.

ü  Turn off the electrical and heat-producing appliances at the end of the day.

ü  Refrain from open flames (i.e. candles, sterno burner, incense burner, etc.) unless they areanintegral part of the work activity (i.e., Bunsen burners in laboratories, torches in welding shops,etc.). Do not leave open flames unattended.

ü  Do not store or use ordinary combustibles (i.e., papers, napkins, cloths, etc.) or flammable/combustible solvents (e.g.,aerosols, paints, etc.) in the vicinity of open flames or hot surfaces.

ü  Know how to safely exit the work area if a fire should occur.

ü  Have at least two (2) exit routes inmind and walk through them to assure your safe response. Always observe a fire alarm.

ü  Convene in the predetermined safe gathering location.

ü  Use appropriately designed tools for handling hot equipment or surfaces (don’t improvise withdish towels, rags, etc.).


Classes of Fires

The Fire Protection Association categorizes fires by class. Newer fire extinguishers use a picture/ labeling system to designate which types of fires they are to be used on. Older fire extinguishers are labeled with colored geometrical shapes with letter designations. Icons for both are shown below. Many extinguishers are designed for more than one type of fire and will therefore be labeled with more than one designator.

ClassA – Trash, Wood, Paper

Class A fires involve ordinary combustible materials--paper, wood, fabrics, rubber, and many plastics. Quenching by water or insulating by a multipurpose (ABC) dry chemical agent is effective.

ClassB - Liquids, Grease

Class B fires occur in flammable liquids--gasoline, oils, greases, tars, paints, lacquers, and flammable gases. Dry chemicals and carbon dioxide agents extinguish these fires.

Class C - Electrical Equipment

Class C fires take place in live electrical equipment--motors, generators, switches, and appliances. Nonconducting extinguishing agents such as dry chemicals or carbon dioxide are required to extinguish them. Fire extinguishers for the protection of delicate electronic equipment shall be selected from types specifically listed and labeled for Class C.


ClassD - Combustible Metals

Class D fires occur in combustible metals such as magnesium, titanium, zirconium, sodium, lithium, and potassium. Sodium carbonate, graphite, bicarbonate, sodium chloride, and salt- based chemicals extinguish these fires. There is no picture designator for Class D extinguishers.

ClassK - Cooking Oil Fires.

Class K fires occur in cooking appliances that use combustible cooking media (vegetable or animal oils and fats).

Types of Fire Extinguishers

• Multipurpose Dry Chemical for Class A, B, and C Fires. The monoammonium phosphate agent is inexpensive and electrically nonconductive but leaves a powdery residue that can damage equipment. This type of extinguishing agent is not good for hidden fires.
• Water for Class A Fires. This type of extinguishing agent is not appropriate for areas with Class C hazard potential because water will conduct electricity.

• CO2 for Class B and C Fires. Carbon dioxide is a colorless, odorless gas that leaves no messy residue to damage equipment. This type of extinguishing agent is good for reaching hidden fires, however, the heavy vapor settles out, limiting the total discharge range to approximately 8 ft. (2.4 m). Carbon dioxide may also cause thermal (cold) and static (shock) damage.

• Dry Chemical for Class B and C Fires. The potassium bicarbonate and sodium bicarbonate extinguishing agents are extremely effective against Class B fires and are electrically nonconductive. They are considered non-toxic and cleanup may be accomplished with a vacuum cleaner or broom and dustpan.

• Dry Chemical for Class D Fires. Extinguishing agents include sodium carbonate, salt, graphite, bicarbonate- and sodium chloride-based chemicals. These agents are not equally effective on all combustible metal fires. Be sure the extinguishing agent chosen will be effective on the combustible metal present, as using the wrong extinguishing agent can increase or spread the fire.

• Wet Chemical for Class K Fires. Potassium acetate is the agent specifically listed and labeled for use on Class K fires. Portable Class K fire extinguishers are intended to supplement automatic fire extinguishing systems.

Ratings of Fire Extinguishers

The fire rating of an extinguisher provides a guide to its extinguishing ability.,

Class A and Class B fire extinguishers carry a classification on their nameplates that consists of a numeral followed by a letter. The numeral indicates the approximate relative fire extinguishing capacity of the extinguisher on the class of fire, which is identified by a letter. For example, a 4-A extinguisher has approximately twice the extinguishing capacity as 2-A extinguisher.

Class C and D extinguishers carry only the symbol and have no numerical rating. Fire extinguishers and extinguishing agents for use with Class D hazards shall be of types approved for use on the specific combustible metal hazard. This should be detailed on the fire extinguisher nameplate.

Location of Fire Extinguishers

Fire extinguishers are required to be conspicuously located where they will be readily accessible and immediately available in the event of fire. Preferably, they shall be located along normal paths of travel, including exits from areas. Extinguisher placement must fulfill both distribution and travel distance requirements. Fire extinguishers must not be obstructed or obscured from view. In large rooms, and in certain locations where visual obstructions cannot be completely avoided, means shall be provided to indicate the extinguisher location.

Scattered or widely separated hazards must be individually protected. A fire extinguisher in the proximity of a hazard shall be carefully located to be accessible in the presence of a fire without undue danger to the operator. Portable fire extinguishers must be installed securely on the hanger, or in the bracket supplied by the extinguisher manufacturer, or in a listed bracket approved for such purpose, or placed in cabinets or wall recesses.

Number of Fire Extinguishers Needed

The number of extinguishers needed is determined by the authority having jurisdiction (usually the local or state fire marshal). This determination is based on the rapidity with which a fire may spread, the intensity of the heat that may develop, the travel distance (actual walking distance) from any point to the nearest fire extinguisher, and the accessibility of the fire.

Use of Extinguishers

Any person who is designated or intends to use a fire extinguisher must be trained in its use.


Undergraduate Teaching

Lectures: it’s the main mode is theoretical teaching for undergraduate students. The course work is divided among all the faculty members in the beginning of the session according to their respective thrust areas. The teaching schedule for the entire session is passed by the members of the BOS of the department.

Clinical demonstrations: undergraduate students must be exposed to different clinical procedures through appropriate demonstrations by faculty members.

Problem based learning: it mainly includes clinical teaching. Every faculty member on his/her OPD day must take at least 45 minutes of clinical teaching mainly based on a particular clinical problem and then outlining the etiology, pathogenesis and management of that particular problem.


  • To ensure that the learning environment of its dental education program is conducive to the ongoing development of explicit and appropriate professional behaviors in its dental students and faculty.

  • Professionals demonstrate adherence to the highest standards of personal, professional, and academic honesty and integrity.

  • To periodically evaluate the learning environment in order to: a) identify positive and negative influences on the maintenance of professional standards b) implement appropriate strategies to enhance positive and mitigate negative influences c) identify and promptly correct violations of professional standards

  • To not allow our conduct to negatively impact on others' learning or clinical activities

  • To not discriminate against students on the basis of such grounds as age, race, colour, ancestry, place of origin, ethnicity, political beliefs, religion, marital status, family status, physical or mental disability, sex, sexual orientation or gender identity

  • To communicate respectfully with others both verbally and in writing

  • To respect the privacy and confidentiality of those to whom we owe that duty

Financial Records

1. Register for purchase committee meetings

2. Register for record of all the instruments in the department

3. Register for record of repair of various items

4. Register for consumables items

5. Indent book register

Clinical Work Records

1. Register for general patient registration in UG CLINIC

2. Register for student patient registration in UG CLINIC

3. Register for patient record in PG CLINIC

4. Register for daily work done record of Consultants, Postgraduates, Undergraduates, Interns,


5. Register for equipment allocation to consultants & postgraduates

Official Work Records

1. Register for Received documents

2. Register for Dispatch documents

3. Register for departmental meetings        

4. Register for Board of Studies

5. Register of leave record of Teaching & Non-Teaching

6. Register for attendance of Teaching, Non-Teaching, post graduates, Undergraduates, Interns

7. Register for duty of teaching & non-teaching during holidays.

8. Register for Budget Controlling, Consumable & Permanent Stocks.


  • Official Working Hours 8:00 AM – 4:00 PM with one hour lunch break

  • Maintaining records of all the documents received and dispatched from the department

  • To put up all the received documents before the chairperson

  • To carry out the duty in accordance with the comments of the chairperson.

  • To make arrangements for the exams conducted in the department

  • Filing documents in their respective files (Office file/Personal file/Circular file/ Notice Board file/ PG file/NAAC/IQAC/File for Minutes of BOS).

  • To maintain all the details of purchases and expenditure made by the department.

  • The following record registers are maintained by the office

  • To make arrangements for the DCI Inspections, B.O. S., and other Meetings.

  • To prepare and maintain the monthly patient record.

  • To prepare the monthly attendance record of Teaching, Non Teaching, Residents & Interns.


  • Observe social distancing measures at all times (minimum 2 meters)

  • Thermal screening of patient

  • Minimize the patient crowding in the waiting area.

  • Clear safety standards for PPE & IPC

  • Appropriate sequencing and scheduling, management, discharge and referral of patients,

  • Using one-way entry/exit for patient flow

  • Cleaning and decontamination of area before and after every patient daily

PPE: personal protective equipment

IPC: infection prevention & control



  • Surfaces that are likely to be contaminated by the dental surgeon handling it or by the spill or spatter of oral contaminants should be disinfected. Surfaces touched by the dental surgeon are called TOUCH SURFACES.

  • E.g. unit handles, various controls, hand piece, 3 way syringe, photodynamic unit etc. These instruments need to be treated with disinfectants or covered with a protective barrier.

  • The surfaces which are contaminated by contact with soiled instruments are called


  • E.g. instrument trays, tube and hand piece holders.

  • SPLITTER SURFACE is any surface which is not a touch or transfer or instrument surface and is within few feet of the oral cavity e.g. the dental chair surface. These surfaces are not cross contamination surfaces.

  • Prevention of contact by touching and elimination of spill and spatter is ideal for preventing infection from surfaces. Since it is not possible, two main methods of protection of surfaces are used which are disinfection and barriers

  • Disinfection involves cleaning of surfaces after every patient and application of disinfectant chemical material. These chemicals include—alcohol, iodophore, synthetic phenols, gluteraldehyde, chlorine etc.

  • Dental patient chair: All chair functions should be controlled from a foot switch to avoid possible contamination by use of hand operate switches. Greatest potential for cross contamination is from chair mounted controls. Covering switches with clear plastics, which is replaced between patient sessions, will allow visualization and use without contamination of switches.

  • Task seat or chair: Dentist should not touch seat covering with contaminated hands. Cleaning and disinfecting of porous seat covering may be accomplished with soap and water.

  • Spittoons: Spittoons should be flushed with water, scrubbed and disinfected. Assembly around spittoons can be protected by barriers and removed when contaminated.

  • Cabinetry: The amount of cabinetry should be minimized and they should be made from material that will with stand repeat cleaning and disinfection.


  • All water lines should be flushed for 3-5 minutes if the system has been idle for several hours.

  • After each patient running high speed hand pieces for a minimum of 20-30 seconds to discharge water and air should be done to flush out patient material that have entered during use.

  • Routine disinfection of water lines is possible by using a disinfection solution in water lines while unit is idle.

  • Anti-retraction valves to prevent backflow of patient material into water line should be regularly tested for proper functioning

  • Suck about 1 liter of 1% sodium hypochlorite through the suction line at the end of the day, leave it for overnight. Next day before starting the work rinse with water and use.


  • Materials like sodium hypochlorite 5.25% (1:10 dilution), iodophors like Biocide & combination synthetics (Phenolics, Multicide & Omni II Vitaphine) have the disadvantage of leaving surfaces wet for 10 minutes, which is inconvenient in a busy dental practice.

  • Glutaraldehyde products that are intended to be used as surface disinfectants contain only 0.25% (w/v) glutaraldehyde. However, they should be used with care, as repeated contact may damage the skin.

  • Surfasept S.A is a commercially available disinfection solution which is aldehyde free, contains Isopropyl alcohol, chlorhexidine digluconate and flavoured excipient. It must be sprayed onto the area which must be completely and uniformly moistened then wiped.

  • Surface disinfection can be done by scrubbing the surface with the iodophor-soaked gauze pads and allowed to dry. Then 70% isopropyl alcohol should be used to remove the residue.


ü  Least critical instruments such as Imaging Plate System, Intraoral Sensor, OPG unit should be disinfected.

ü  Quaternary ammonium compounds are cationic surface disinfecting agents. Commonly used ones are Cetrimide and Benzylkonium chloride. Disadvantages with these compounds are that they get inactivated by soap, reduced activity in presence of metal ions common in natural water, reduced effectiveness in presence of organic matter, lack of activity against tuberculosis bacteria and are not sporicidal.

ü  8% solution of formaldehyde in alcohol and 2% solution of activated glutaraldehyde were considered to be two disinfectant of choice.

ü  To disinfect the OPG or RVG machine Switch off  the unit.

ü  Remove all visible soil, if any, with disposable cloth or paper wipe.

ü  No disassembly shall be performed on the unit Dampen (not soak) a lint-free cloth with soap and running water.

ü Thoroughly clean all accessible parts of the unit, including the temporal head clamps, with the dampened lint-free cloth.

ü Dry the unit with hygienic disposable cloth.

ü  Dampen (not soak) a lint-free cloth with a low-level disinfectant.

ü  Wipe thoroughly all accessible parts of the unit with the dampened lint free cloth.

ü  Allow to dry in the open air for a minimum of five minutes.

Cleaning and disinfecting accessories that have contact with mucous membranes

ü  Remove and discard the protective sheath from the accessory.

ü  Remove all visible soil with a disposable cloth or paper wipe. Rinse at least one minute under running water to thoroughly clean the accessory from any excess soil.

ü  Using a soft brush, apply medical enzyme detergent solutions (basically, with a multi-enzymatic formula) to all surfaces of the accessory.

ü  Rinse thoroughly under running water for at least one minute to remove detergent residue.

ü  Dry the accessory with compressed air or a hygienic disposable cloth. Visually inspect the accessory for residual soil.

ü  If soil is visible, either repeat steps two to five, or safely dispose the accessory.

ü  Wrap the cleaned accessory using a standard packaging material for autoclaving.

ü  Steam autoclave at 132°C (270°F) for four minutes or depending on your local regulation you can steam autoclave at 134°C (273°F) for 18 minute

Intra Oral Sensor

ü  Remove the protective hygienic sleeves.

ü  Remove the debris or organic matter from the sensor surface with a disposable wipe or surface brush.

ü  Inspect the sensor for debris.

ü  Repeat cleaning if there is any debris left Disinfect the sensor head with disinfecting wipes or soak it in a disinfecting solution with intermediate-level hospital disinfectant with label claims of tuberculocidal activity eg. A chlorine-containing product, a quaternary ammonium compound with alcohol, a phenolics, an iodophors.


Sterilization can be accomplished in one of several ways. Some of the most common ways that are followed in dental practice include steam autoclave sterilization, dry heat sterilization, chemical vapour sterilization and ethylene oxide sterilization

Instrument Processing

The overall process consists of

  • Holding ( presoaking )

  • Pre cleaning

  • Corrosion control, drying, lubrication

  • Packaging

  • Sterilization

  • Sterilization monitoring

  • Handling processed instruments

·       Presoaking:

Placing instruments in presoak solution until time is available for full cleaning prevents drying, begins to dissolve organic debris and in some instances begin microbial kill. Presoak solution consists of detergents, enzymes, or detergents containing disinfectants. Used solution should be discarded at least once a day.

·       Cleaning:

Blood, saliva and materials on instrument can insulate underlying microorganisms from sterilizing agents. Cleaning reduces this bio burden. Cleaning solutions with antimicrobial activity can eliminate build up of contaminants as the cleaning solution is being repeatedly used.

Hand cleaning:  It is an effective method if performed properly. Heavy utility gloves and protective eyewear should be worn during hand cleansing of instruments. Instruments should be immersed in the detergent solution and then scrubbed with soft brush.

·       Mechanical/Ultrasonic cleaning:

ü  Coupling of powerful ultrasonic vibrations with cold disinfection increases the effectiveness of the process.

ü  In a densely packed pile of instruments, there is only a thin layer of disinfectant around each instrument; vibration assures penetration of a properly concentrated solution into every area of every instrument.

ü  Cleaning solution specifically recommended for use in ultrasonic cleanser should be used in proper dilution. The instruments are kept in the ultrasonic cleanser basket and submerged in the cleaning solution.

·       Ultrasonic Cleaner:

ü  The cleaner should be covered and operated for 6-10 minutes or until no visible debris remains. If instrument cassettes are used cleaning time is increased to 15 minutes.

ü  After cleaning instruments are thoroughly rinsed. Cleaned instruments must be considered contaminated and handled with gloved hands.



It is an electrolytic process in which the contact of two dissimilar metals or dissimilar areas within a single metal sets up a potential difference resulting in an electron flow. The electron flow leaves behind reactive ions that readily combine with atmospheric oxygen to form oxides (rust). Conditions such as extreme temperatures, physical abrasion, galvanism, or reactive extraneous ions that disrupt the chromium oxide layer will render the steel vulnerable to corrosion. Instruments made of carbon or 400 series steel are more susceptible than those of 300 series steel. Recent studies showed no significant difference in mean wear whether sterilized with steam autoclave or dry heat.

To reduce corrosion

  • Clean and remove debris from the instruments and rinse with distilled water.

  • Avoid tap water which contains dissolved alkali and metallic ions.

  • Water must be deionized and of good quality.

  • Keep the pH of steam above 6.4; otherwise pitting will occur.

  • Chrome plated instruments and stainless steel instruments should be sterilized separately because the electrolyte action can carry carbon particles from the exposed metal of a chromium plated instrument and get deposited on stainless steel.

  • It is better to keep the instruments in wrapping. Detergents with chloride bases should be avoided because chloride residue unites with steam to form HCl.

  • Detergents with pH of more than 8.5 may disrupt chromium oxide layer.

Packaging: Cleaned instruments should be packed prior to sterilization to protect them from recontamination after sterilization. The instruments should be packed in an appropriate wrapping material before sterilization. A wrapping material designed for a particular type of sterilizer should be used with the sterilizer. E.g. A single layer cloth wrap for steam sterilization, self sealing polyfilm paper pouches for chemical vapour sterilization, paper wrap for dry heat sterilization. Wrapping material should be self sealing or heat sealed or double folded and sealed with appropriate tape.



ü Moist heat denatures and coagulates protein of microorganisms. The sterilization is due to latent heat of vaporization present in moist heat.

ü  When steam condenses on contact with cooler surfaces, it becomes water and gives latent heat to that surface.

ü  This principle is used in autoclave.

ü  Temperature required is 121°C for 20 minutes at 15 pounds pressure. For practical considerations high pressure vacuum models are operated at a temperature of136°C for 5 minutes at 30 pounds pressure.


ü  Ethylene oxide at normal temperature is a gas with very high penetrating ability. It acts by alkylating the amino, carboxyl, sulphydril groups in protein molecules.

ü  It reacts with RNA and DNA.

ü  It sterilizes heat sensitive


  • Steam, dry heat, chemical vapour and ethylene oxide sterilization are acceptable for hand pieces.

  • Run the handpiece over a sink for 20 seconds allowing water to flush through the hand piece thoroughly. Remove the bur.

  • Scrub the hand piece thoroughly with detergent and water, to remove any debris. Rinse and dry the hand piece.

  • Lubricate the hand piece with a good quality oil recommended by the hand piece manufacture

  • Expel excess oil by running the hand piece for 2 seconds, after replacing the bur or hanging the hand piece in a hand piece rack.

  • Remove the bur, if replaced. Clean the fiber-optic, bundle ends with alcohol Place the hand piece in a clear view sterilisation pouch, together with a chemical indicator strip

  • Sterilise in an autoclave or chemiclave, according to the manufacturer's instructions. Do not
    leave the handpiece in the steriliser after sterilisation cycle is complete.

  • Remove the hand piece from the bag, insert the bur, and use.


ü  Burs become very contaminated and are classed as critical items; they must be sterilised after use.

ü  Diamond and carbide burs may be safely autoclaved with minimal damage but carbon-steel burs are damaged by autoclaving.

ü  Carbon-steel burs may be sterilised by using a chemical vapoursteriliser. A glass bead steriliser at 218ºC for 10 seconds may be used to sterilise grossly contaminated carbon-steel burs during the same dental procedure.




  • Turn on the switch manually and check for all the functions, prior to seating the patient on dental chair. Open the valve for compressor and waterlines.

  • The equipment and surfaces subject to contamination should be cleaned and disinfected.

  • Adjust the position and height of dental chair so as to make the patient comfortable and keeping in mind the ergonomics of the operator.

  • At the beginning of each clinical session, flush water through waterlines for 2-3 minutes.

  • The surfaces of the dental unit a recovered with disposable food grade cling foil plastic. Use of disposable glass and suction tips for each patient is done.

  • The dental operator, assistant and all personnel within two meters of patient cares should wear impervious surgical gown/ scrub with well-fitting N-95 mask.

  • Sensor taps or taps with elbow handles should be preferred.

  • Avoid use of towels; Paper towels are preferred

  • Pre-procedural mouthwash (povidone-iodine, chlorhexidine, chloride-dioxide) for at least15 seconds may be helpful in transient reduction of viral load.

  • Infection control guidelines with special considerations for aerosol or splatter generating procedures should be followed:

    • High vacuum suction with minimum suction capacity of 6.6 litres per minute.

    • Use faceshield.

    • Use rubber dam wherever possible.

    • Keep adequate follow up time in between two procedures.

  • Clean        and               disinfect         equipment                 and     operatory                 surfaces          with     1% sodium hypochlorite or 70% alcohol for appropriate contact times.

  • Remove soiled gown as soon as possible. The procedures and prescription are recorded only after doffing the PPE.

  • Patient to perform hand hygiene and to be provided with review/ follow- up instructions.

  • Remove the water bottle and clean it every day after work and flushout disinfectant through the waterlines.

  • Turn off the valves for compressor and waterlines and switch off the dental chair unit after work.


SOP of Oral Medicine OPD-All patients having dental problems of Aligarh & surrounding districs as well as refered patients from PHC & Dental clinics were thoroughly examined in Oral Medicine OPD by expert Oral Physician (Faculty members of departments) and dignosis were made keeping all protocol provided by MOH & Govt Of India.

The medicinal & noninvasive  treatments were carried out and patients requiring specific dental procedures were refered to different dental OPD.

Specific dignosis procedures were carriedout such  as screening by Velscope for early detection of mouth cancer.Also some other non-invasivwe treatment modilities such as TENS & Photodynamics therapy carriedout in same OPD.

SOP of Oral & Maxillofacial Radilogy -All patients requiring Dental & Maxillofacial Radiographs were carried out by expert & exprienced radigraphic  technicians.

Both convetional and digital intra & extra Oral radiograph were done here. Specialised Radiographs such as OPG,lat.Ceph and differnt TMJ view were performed under supervision of Oral & Maxillofacial Radiologist.

SOP of Oral Pathology Lab-Histopathological studies of Oral & maxillofacial lesions were performed in Oral Pathology lab by expert & exprienced Oral & Maxillofacials pathologists(Faculty members of departments).