Month: October 2022

Importance of Differential Pressure in Pharmaceutical


Differential pressure in pharmaceuticals helps to prevent contamination and cross-contamination. A Magnehelic gauge device is used to measure the pressure difference between the two adjacent sections. The gauge has two inlets point for the pressure that is connected to the area being monitored.

Differential pressure is the pressure that differentiates between the pressures of the atmosphere of one area (process area) to other surrounding areas (corridors). It is measured in pascals and wc of Hg. Magnehelic gauge is used to records the differential pressure.

Why is Differential Pressure important in Pharmaceuticals?

Differential pressure prevents contamination and cross-contamination during the product manufacturing process; during the process, the air becomes contaminated. If Differential pressure is not maintained within limits, the contaminated particles may enter or mix up with the fresh air and contaminates other manufacturing products.

Differential pressure must be checked and recorded every Two Hours ± 15 minutes in the manufacturing area where the product is directly exposed, and every Four Hours ± 15 minutes where the product is directly not exposed or as per the given SOP “Records of area Differential Pressure.”

WHO guidelines on Differential pressure

According to the WHO Guidelines annex 8, the airflow flow should be from a clean area to a cubicle area to avoid contamination. The processing area should be negative ( in the case of Oral Solid Dosage) compared to the corridor area to ensure airflow from the aseptic area to the non-aseptic area.

Generally, dust generates in the process area, so the corridor should be at higher pressure to stop dust flow in the corridor area.

Importance of the airlock in Differential Pressure

Airlock in pharmaceuticals is used to transfer the materials. It is advised to keep positive pressure in the corridor than the processing or manufacturing area. The positive airlock should be there to minimize direct airflow from process air to the Non-Process area, which helps control the direct contamination in the processing area.

Airflow Direction in the Non-sterile area with Respect to Corridor

keep negative pressure inside the controlled area(process area) as compared to the corridor area(positive pressure) to prevent cross-contamination.

Negative pressure means clean airflow from the corridor going into the process room, and contaminated air in the process area flows out from the riser’s filters. These types of air systems are suitable for OSD (oral solid dosage), steroids, and chemotherapy products.

Differential Pressure in a Sterile area with respect to Corridor

Cross-contamination of one product with the other products is an issue, but in a sterile area (injection filling), there are more chances of microbial contamination; that’s the reason positive pressure is maintained inside the sterile area as compared to the corridor.

Way to maintain Pressure in Area Recovery Test for HVAC  

It’s important to perform a recovery test as per the scheduled time to check the pressure differential in pharmaceuticals produced by the HVAC system. The calibration of the Magnehelic gauge must be checked regularly.

Building construction:

To take care of the integrity of the unit, airtight doors, a Gap between the door and floor, and window installation is required to stop the loss of pressure through the gap. An alarm for a sign should be available for workers to understand any loss of atmospheric pressure.

Types of audit in pharmaceutical industry


Introduction :

Audit is the examination or inspection of various books of accounts by an auditor followed by physical checking of inventory to make sure that all departments are following documented system of recording transactions. It is done to ascertain the accuracy of financial statements provided by the organisation.

This is the generic definition of an “audit”.

The keyword is “examination”. However, this definition of the term audit is very misleading in the pharmaceutical industry (drug substance, drug product, pharmaceutical formulation intermediates, medical devices, biological, veterinary medicine, Ayurvedic and homeopathy medicines), the definition need to be elaborated.

Quality audit is the process of systematic examination of a quality system carried out by an internal or external quality auditor or an audit team. Quality of a product is not “built in” in the laboratory. A quality culture has to be introduced into the organization. In simple words, quality is customer satisfaction and also compliance to minimum regulatory requirements based on the products. In India, the quality of pharmaceutical for the domestic market is controlled by the requirements as lead down in the Indian pharmacopoeia or national formulary and in many cases, specifications developed by the manufacturers known as “in house specification” (I.H.S). The permission to market any formulation, drug substance, API is granted by state FDA and CDSCO (Central Drug Standard Control Organization).On submission of the manufacturing data and quality test parameter. The team from the state FDA and CDSCO come down for an inspection in other words an audit. It is an important part of an organization’s quality management system and is a key element in the ISO quality system standard, ISO 9001.

The Drug and Cosmetics Act 1940 and Rules there under 2018, state that the manufacturing unit must have a quality control laboratory. The laboratory in itself along with the microbiology laboratory cannot control the quality. It can only assess the quality. The laboratory will require and additional tool to “assure quality”.

The laboratory should not be mistaken only for quality control but also include quality assurance. The tool for the personnel responsible for quality assurance is the audit. Conducting an audit or facing an audit is an integral function of quality assurance.

Quality audits can be integral part of compliance or regulatory requirements. One example is the US Food and Drug Administration, which requires quality auditing to be performed as part of its Quality System Regulation (QSR) for medical devices (Title 21 of the US Code of Regulations, part 820) and anything sold to the consumer. The ICH (International Conference for Harmonization) guidelines and also WHO (World Trade Organization) guidelines require audit to be conducted internally as a part of compliance to GMP (Good Manufacturing Practice).

The objectives of the audit either by internal assessment or external assessment are compliance to quality, documentation, and facility etc. to ensure a safe efficacious product is delivered 365 days 24 by 7.

Types of Audits:

ISO 19011:2018 defines an audit as a “systematic, independent and documented process for obtaining audit evidence [records, statements of fact or other information which are relevant and verifiable] and evaluating it objectively to determine the extent to which the audit criteria [a set of policies, procedures or requirements] are fulfilled.” There are three main types of audits namely Internal and External.

• Internal Audit:

Internal audit is carried out by a team of interdepartmental personnel at least twice a year to assess the compliance to quality management system and customer satisfaction.

The customer satisfaction is assessed by viewing return good documentation and customer complaints and regulatory recalls. This type of audit is an examination of the tool used to measure quality itself. An internal quality audit seeks to evaluate an organization’s Electronic Quality Management System (EQMS). The quality documentation and processes managed by the software solution are reviewed to ensure maximum efficiency and high-quality product outcomes.

The software manual is audited to ensure all critical areas of the solution are covered and all key employees readily have access to the document. Work instructions are audited to ensure conformity to standard operating procedures and to confirm quality processes are meeting targets.

Production Process Audit: Production team members usually get an examination (audit) when Operator Acceptance or Certified Operator programs are in place, or when skills management re-qualifications are required. Auditors evaluate changes to processes, evidence of training, past activity for escapes, non-conformance, and conformity inspections of operator accepted product as part of the re-qualification.

In pharmaceutical industry, there are many highly skilled operations in manufacturing area e.g.

  • Operation of tablet compression machine
  • Operation of Rapid Mixer Granulator
  • Strip & blister packing machines.
  • High speed automatic capsule filling machine
  • Operation of autoclaves etc.

Here, the desired skill of the operations is a must. These skilled must be evaluated and if needed the operations should be provided with necessary skill/operational training.

Safety Audit: A safety audit looks at the plans and procedures designed to protect the safety of company employees. This type of audit can include a review of equipment operation or an examination of organizational procedures to ensure routine safety. Successful safety policies prevent injuries and accidents from occurring and improve overall employee well-being.

Facility Audit: A facilities audit addresses quality concerns of a corporation’s assets. Components of a facilities audit can include a review of building systems such as HVAC, water system, manufacturing equipment or technology. Processes associated with these facilities are reviewed to ensure safety and identify improvements that could affect quality outcomes.

Facility and Equipment Validation comes to our help in seeing that every thing is in order FDA officials give very high importance to such facility and equipment validation activities. Audits can point out deficiencies in this area.

Risk Assessment Audit: A risk assessment is a process that identifies potential workplace hazards, and then categorizes each risk so preventative measures can be put into place. An audit of this type helps companies put an effective risk mitigation strategy into action. When all risks have been identified, preventative measures can be prioritized, preventing adverse workplace and economic consequences.

Product audit: This type of audit is an examination of a particular product or service, such as hardware, processed material, or software, to evaluate whether it conforms to requirements (i.e., specifications, performance standards, and customer requirements).

System audit: An audit conducted on a management system. It can be described as a documented activity performed to verify, by examination and evaluation of objective evidence, that applicable elements of the system are appropriate and effective and have been developed, documented, and implemented in accordance and in conjunction with specified requirements.

External Audit:

  • Customer Audits
  • Regulatory Audits
  • Vendor Audits
  • Laboratory Audits
  • Customer Audits: Any customer desirous doing business with pharmaceutical organization like to carried out a due diligence study of the QMS (Quality Management System) being followed.
  • Regulatory Audits: It is carried out either by the state FDA or CDSCO or WHO or any other international regulatory agency before they give a no objection certificate for manufacture and sale to that particular country of the pharmaceutical product, certifying that QMS is in compliance with minimum requirements. Regulatory audits are conducted to verify the data collection process is systematically reviewed to identify possible areas of non-conformance. Examples of regulatory agencies include international regulatory audits by USFDA, MHRA, TGA, MCC etc.
  • Vendor Audits: This audit is required before purchasing any raw material from any vendor to assess whether basic QMS and GMP are being followed. Vendor audits allow an organization to collaborate in real time directly with its suppliers. By auditing the supply chain, companies can control the quality of its suppliers and sub- tier suppliers and introduce accountability for poor performers. Key performance indicators (KPIs) quickly identify areas for improvement. With this level of transparency, suppliers are able to view purchase order activity such as receipt and inspection history in order to collaborate or non-conformance and corrective actions.
  • Laboratory Audits: Whenever sophisticated testing with instruments not available in the in house laboratory, the services of an external laboratory may be utilizing subject to the organization carrying out a comprehensive laboratory audit compliance to GLP (Good Laboratory Practice) and GDP (Good Documentation Practice) and GDIP (Good Data Integrity Practice). Laboratory audits should also look into the analytical methods validation documentations.

 Objectives of a Quality Audit :

Quality is always dynamic and never static. It is always on the move. Quality demands continuous improvement.

The objective is:

  • To determine the conformity or non-conformity of the quality system in meeting the specified requirements.
  • To determine the effectiveness of the implemented quality in meeting the specified Quality objectives.
  • To provide the audit team with an opportunity to improve the Quality system.
  • To meet the regulatory requirement.
  • To permit listing of the audited organizations Quality systems in a register.
  • Audits are intended to verify that manufacturing and control systems are operating under a state of control.
  • Audits permit timely correction of potential problems.
  • Audits can be used to establish a high degree of confidence to remain under an adequate level of control by managements.
  • Assess your document management system.
  • Evaluate your locations and any site-specific conditions.
  • Assess your understanding of the requirements of the standard.
  • Agree the scope of your Documented Management System, processes and location(s) and related statutory and regulatory aspects and associated risks.
  • Establish your planning arrangements for Internal Audits and Management Reviews.
  • Identify any areas for potential Improvement of the Management System.
  • Evaluate the implementation and effectiveness of your Management System.
  • Assess your performance against key performance objectives and targets (monitoring, measuring, reporting and reviewing).
  • Evaluate your legal compliance, operational control of processes, Internal Audits, Management Reviews and Policies.
  • Evaluate links between the normative requirements, policy, performance objectives and targets, responsibilities, competence of personnel, operations, procedures, and performance data.
  • Identify any areas for potential Improvement of the Management System.
  • Ensure your Management System has continued to fulfil requirements between Audits.
  • Ensure Internal Audits and Management Review has been performed to programme.
  • Review actions taken on nonconformities identified during previous Audits.
  • Evaluate your handling of any complaints.
  • Evaluate the continued effectiveness of the management system, with regard to achieving your objectives.
  • Evaluate your legal compliance and performance.
  • Evaluate your progress of planned activities aimed at continual improvement.
  • Ensure continuing operational control.
  • Review any changes to your organisation since the previous Audit.
  • Identify any areas for potential Improvement of the Management System.