Basic Principles of Lab Works

I. Pre-Lab Principles

1. Familiarize Yourself with the Lab

• Take a tour of the lab to understand the layout and location of equipment, safety features, and emergency exits.
• Read and understand lab manuals, guidelines, and protocols.
• Familiarize yourself with lab-specific safety procedures and emergency response plans.

2. Read and Follow Protocols

• Carefully read and understand established protocols and procedures for experiments and tests.
• Follow protocols precisely, and do not deviate from them without proper authorization.
• Take notes and record any modifications or variations made to protocols.

3. Wear Proper Personal Protective Equipment (PPE)

• Wear lab coats, gloves, safety glasses, and other required PPE to protect yourself from chemicals, biological agents, and physical hazards.
• Ensure PPE is in good condition and properly fitted.
• Remove PPE when leaving the lab and dispose of it properly.

II. Safety Principles

HAZARDS IN A PATHOLOGY LABORATORY AND RELATED SAFETY PRECAUTIONS

There are several types of potential hazards to be faced in a Pathology Laboratory. All of the staff working in the laboratory must be fully aware of these, should make all possible efforts to prevent these and should be prepared to face them if any of these occur. The hazards in a Pathology Laboratory mainly arise from: 

1. A fault in the construction of the building and its various installations. 
2. The handling of infected specimens. 
3. The handling of chemicals. 
4. Faulty apparatus. 

These hazards can be broadly grouped into the following five categories: 

1. Hazards to the premises. 
2. Hazards to the environment. 
3. Hazards to patients. 
4. Hazards to staff members. 
5. Hazards to equipment.

HAZARDS TO THE PREMISES 

Like any other building, the premises of the Pathology Laboratory are prone to the hazard of fire. The chances are higher than in an ordinary building because of the multiplicity of electrical connections and the use of flammable material. The preventive measures to be adopted include: 

1. The assurance of a good-quality electrical system and one that is appropriate for the electrical load of the laboratory, installed under the supervision of a qualified engineer 
2. Timely replacement of any sparking socket 
3. Avoidance of the use of temporary extensions and naked wires 
4. The safe and appropriate storage of flammable material 
5. The safe and appropriate storage of gases used in the laboratory 
6. Avoidance of unnecessary use of flammable items e.g., foam, wooden furniture, carpets, etc. 
7. Periodic training of staff members re firefighting techniques 
8. The installation of a fire-alarm system 
9. The provision of fire-fighting equipment, e.g. water hoses, fire extinguishers, sand, etc., at suitable and appropriate locations 
10. Displaying the telephone numbers in each room of the laboratory of fire stations located in the vicinity 
11. Provision of emergency fire exits and stairs. 

In case a fire does occur, the following should be done: 

1. Immediately call for help. 
2. Shut off the electric supply and gas supply. 
3. Evacuate any patients, women and children. 
4. Remove flammable material that is near the site of the fire. 
5. Take the nearest fire extinguisher or any other fire-fighting equipment and try to extinguish the fire.

HAZARDS TO THE ENVIRONMENT 

Hazards to the environment are often ignored. These arise from the inappropriate disposal of laboratory waste, including: 

1. Infectious material collected from the patients 
2. Used syringes 
3. Poisonous chemicals 
4. Radio-active material 
5. Discarded tissues and organs
6. Polythene and latex material e.g., bags, gloves, gowns, etc. 

The following precautions should be taken to prevent environmental pollution: 

1. All infectious waste, which can be incinerated, should be carefully collected and burned. 
2. All other infectious waste, e.g., urine, faeces, blood, fluids and cultures must be de-contaminated before discharging into the drainage system. 
3. All syringes and needles should be cut into pieces to make them unusable and then destroyed. 
4. All poisonous chemicals should be neutralized before discharging them into the drainage system. 
5. All left-over tissues/organs should either be cremated or buried deep in the soil.
6. Polythene and latex material should be decontaminated and preferably be recycled.

HAZARDS TO PATIENTS 

The most important hazards to patients are: 

1. Transmission of disease 
2. Vasovagal shock 
3. Infection at the site of an invasive procedure 
4. Metabolic complications of some suppression or stimulation tests performed for endocrine disorders.

The following precautions should be taken to prevent these hazards: 

1. Never use the same syringe, needle or canula of any type for two patients.
2. Non-disposable instruments, like bone marrow needles must be properly sterilized as per standard instructions. Still it is advisable to keep a separate set for patients known to be positive for hepatitis or HIV. This set should also be de-contaminated in 0.5-1% of sodium hypochlorite solution for 10 minutes and then autoclaved. 
3. All emergency medicines and equipment including that of cardio-pulmonary resuscitation (CPR) must be on hand where phlebotomies are done or other invasive procedures are performed to treat vasovagal shock. 
4. All staff members performing phlebotomies or other invasive procedures should be fully conversant with CPR procedures. 
5. While performing an invasive procedure, including a phlebotomy, the site should be thoroughly disinfected with alcohol or a suitable iodine preparation. 
6. The puncture site should be kept gently pressed to avoid any oozing and subcutaneous accumulation of blood, to prevent infection. 
7. The premises where stimulation or suppression tests are performed should be fully equipped to meet any emergency situation.

HAZARDS TO STAFF MEMBERS 

Staff members, particularly laboratory technologists, are most vulnerable to all of the hazards. Blood, urine, faeces, CSF and other body fluids may contain highly infectious and potentially lethal organisms. These are collectively referred to as biohazards. Extreme caution is to be exercised while collecting, transporting, processing and disposing these. All biological specimens, regardless of the source, should be considered a bio-hazard. The following precautions must be observed: 

1. Personal protective equipment, e.g. gloves, masks, gowns, etc. must be worn when handling biological specimens. 
2. The practice of hand-washing before and after handling biological material and patients should be inculcated in the staff. 
3. No contaminated equipment or surface should be touched with bare hands. 
4. Stoppers/lids from specimen containers should not be removed unnecessarily. 
5. Mouth pipetting should never be allowed. 
6. All non-disposable equipment should be frequently de-contaminated. 
7. It must be remembered that all unfixed and unstained slides are also infectious. 
8. All sharps, including needles and pieces of broken glass, must be handled with care and disposed off in cardboard containers. 
9. All contaminated medical supplies should be de-contaminated, autoclaved or incinerated. 
10. All spills must be cleaned and surfaces disinfected immediately. 

Adopt the following procedures: 

1. Protect yourself. 
2. Pick up sharps and glass pieces with forceps or pieces of cardboard. 
3. Clean surfaces with household aqueous detergent. 
4. Disinfect with household bleach. The undiluted solution of good-quality household bleach contains 5-25% sodium hypochlorite, which is equal to 5000 mg/L of chlorine. For porous surfaces use a 1:10 dilution of this solution but for hard surfaces a 1:100 dilution is sufficient. 
5. Absorb with absorbent wool or paper towels. 
6. Rinse with water and allow the surface to dry.

HAZARDS TO EQUIPMENT 

In the modern laboratory most of the equipment is expensive and requires due care against any damage. There are three main sources of damage to the equipment: 

1. Damage due to a faulty electric supply. 
2. Damage due to the accumulation of corrosive material in various parts. 
3. Damage due to rusting. 

In our country the electric supply is not uniform. Not only the voltage fluctuates frequently but there are frequent shut-downs, sometimes for a moment. This is a potential source of damage to all equipment requiring electric supply. Computerised equipment is particularly vulnerable. The following precautions should be taken to avoid such damage: 

1. All electric connections must be installed with good-quality circuit breakers. 
2. If possible, voltage stabilizers should be used. Circuit breakers should always be used with these. 
3. Uninterrupted power supplies (UPS) should be used with computerized equipment to avoid the need for a repetition of tests, the loss of data and damage to equipment. 
4. A back-up electricity generator should be used for prolonged power shutdowns. 

The preventive maintenance of all equipment at regular intervals will safeguard against the accumulation of corrosion and rusting. All technologists should be trained as this increases the life of the equipment. 

SUMMARY OF SAFETY RULES 

1. Good personal habits 

1. Use personal protective equipment. 
2. Tie back long hair. 
3. Do not eat, drink or smoke in the work area. 
4. Label all containers in bold. 
5. Place warning signs at appropriate locations in the work area. 

2. Good laboratory techniques 

1. Do not use unfamiliar equipment without the proper training. 
2. Do not perform any technique without the proper training. 
3. Read the labels before using any reagent. 
4. Observe due precautions while transferring and mixing chemicals. 
5. Do not pipette with the mouth. 
6. Wash your hands before and after work. 
7. Good housekeeping practices a. Keep the work area free of sharps, glassware and chemicals. 
8. Store everything properly, according to the instructions of the manufacturer and according to safety regulations.

III. Quality Control Principles

1. Use Calibrated Equipment

• Ensure equipment is properly calibrated and maintained.
• Follow manufacturer instructions and lab guidelines for calibration and maintenance.
• Use calibrated equipment only for its intended purpose.

2. Follow Standard Operating Procedures (SOPs)

• Adhere to established SOPs for testing and analysis.
• Follow SOPs precisely, and do not deviate from them without proper authorization.
• Take notes and record any modifications or variations made to SOPs.

3. Maintain Accurate Records

• Keep detailed, accurate records of experiments, results, and observations.
• Record data promptly and legibly.
• Store records securely and maintain them for the required period.

IV. Data Management Principles

1. Record Data Accurately and Legibly

• Use clear, concise language and proper units.
• Record data promptly to avoid errors or omissions.
• Review data for accuracy and completeness.

2. Store Data Securely

• Use designated storage areas, such as locked cabinets or secure digital storage.
• Follow lab guidelines and protocols for data storage and security.
• Maintain backup copies of data and store them securely.

3. Analyze Data Critically

• Evaluate data for errors, inconsistencies, and trends.
• Use statistical methods and tools to analyze data.
• Draw conclusions based on data analysis and results.

V. Post-Lab Principles

1. Clean Up Thoroughly

• Dispose of waste properly, including chemicals, biological agents, and sharps.
• Clean equipment and work areas thoroughly.
• Sanitize work areas and equipment.

2. Document and Report Results

• Summarize findings and report results to relevant parties.
• Include detailed descriptions of methods, materials, and procedures.
• Provide conclusions and recommendations based on results.

3. Review and Improve Procedures

• Identify areas for improvement and refine procedures for future experiments.
• Document changes and updates to procedures.
• Share knowledge and best practices with colleagues.

Code of professional conduct for medical laboratory personnel

• Be dedicated to the use of clinical laboratory science to benefit mankind. 
• Place the well-being and service of patients above your own interests. 
• Be accountable for the quality and integrity of clinical laboratory services.
• Exercise professional judgement, skill, and care while meeting established standards.
• Do not misuse your professional skills or knowledge for personal gain, and never take anything from your place of work that does not belong to you. 
• Be at all times courteous, patient, and considerate to patients and their relatives. Safeguard the dignity and privacy of patients.
• Do not disclose to a patient or any unauthorized person the results of your investigations and treat with strict confidentiality any personal information that you may learn about a patient. 
• Respect and work in harmony with the other members of your hospital staff or health center team. 
• Promote health care and the prevention and control of disease. 
• Follow safe working practices and ensure patients and others are not put at risk. Know what to do should an accident or fire occur and how to apply emergency First Aid. 
• Do not consume alcohol or take unprescribed drugs that could interfere with your work performance during laboratory working hours or when on emergency stand-by. 
• Use equipment and laboratory-ware correctly and do not waste reagents or other laboratory supplies. 
• Strive to improve professional skills and knowledge and adopt scientific advances that benefit the patient and improve the delivery of test results.
• Fulfill reliably and completely the terms and conditions of your employment.

References

• AFIP Manual of Laboratory Medicine 5th Edition, Muhammad Tahir Khadim, Parvez Ahmed, Muhammad Mukarram Bashir, Aamer Ikram, Aamir Ijaz, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan, National University of Medical Sciences (NUMS)
• Cheesbrough, Monica. Tropical Health Technology: District Laboratory Practice in Tropical Countries, Part 1. Second edition