Monday, November 21, 2016

Do you Know about Vented, 3 vent, & Non Vented Petri Plates?? Hidden Facts!!!

What is Vent in Petriplates?
Vented Petri dishes have a small lip on the top edge of the dish that allows the lid to sit a little up from the bottom, allowing for some air flow.  Non-vented Petri dishes allow the lid to sit more or less flat on the bottom.
                    Standard Petri Dishes are always vented, so if the don't say vented or non-vented, you should assume they are vented.  "Vented" means that the lid is slightly elevated above the base.  This allows for good, plentiful air exchange.  This is useful when you want to encourage evaporation, for example, when you want to use poured plates as soon as possible, and the plates themselves, or a liquid seeding solution, needs to dry beforehand.  The basic design of the dish tends to maintain sterility because particles would have to go up and over the dish's wall to get inside, and this is rare in normal airflow.
Types of Vent:
1.      Triple vented: aids gaseous exchange. Ideally suited for short term work
2.      Single vented: limits gaseous exchange, minimise evaporation and dehydration. Ideally suited for long term work
3.      Six Vented: Number of vent increases allows more gaseous exchange.
4.      Deep Vented: It allows more gaseous exchange, vent is slightly thick, it is useful plant and tissue cultures
5.      Non-vented: most suitable for anaerobic and long term work

Non Vented Plates:

.  With "non-vented" dishes, the lid fits quite flatly on the base.  While it is not a hermetic seal, the space between dish and lid is extremely small.  This results in even less potential for external contamination and a significantly reduced evaporation rate.  For example a 60mm vented Petri Dish containing 10ml of agar medium typically dries out in 2-3 weeks; whereas, a similar 60mm non-vented dish typically lasts 2-3 months. Except those in very humid climates, prefer the non-vented dishes.  Non-vented dishes provide sufficient air exchange for the worms to breath while greatly increasing the life of the dish.

Wednesday, November 16, 2016

Basic Concepts of FMEA and FMECA?

☄Failure ☄Mode and ☄Effects Analysis (FMEA) and Failure Modes, Effects and ☄Criticality ☄Analysis (FMECA) are methodologies designed to identify potential failure modes for a product or process, to assess the risk associated with those failure modes, to rank the issues in terms of importance and to identify and carry out corrective actions to address the most serious concerns

👉🏻Although the purpose, terminology and other details can vary according to type (e.g. Process FMEA, Design FMEA, etc.), the basic methodology is similar for all👉🏻This article presents a brief general overview of FMEA / FMECA analysis techniques and requirements

👉🏻FMEA / FMECA Overview

👉🏻In general, FMEA / FMECA requires the identification of the following basic information:

☄Item(s)☄Function(s)☄Failure(s)☄Effect(s) of Failure ☄Cause(s) of Failure ☄Current Control(s) ☄Recommended Action(s) Plus other relevant details

👉🏻Most analyses of this type also include some method to assess the risk associated with the issues identified during the analysis and to prioritize corrective actions👉🏻Two common methods include:

👉🏻Risk Priority Numbers (RPNs)Criticality Analysis (FMEA with Criticality Analysis = FMECA)

👇🏼Published Standards and Guidelines

👉🏻There are a number of published guidelines and standards for the requirements and recommended reporting format of FMEAs and FMECAs👉🏻Some of the main published standards for this type of analysis include SAE J1739, AIAG FMEA-4 and MIL-STD-1629A👉🏻In addition, many industries and companies have developed their own procedures to meet the specific requirements of their products/processes👉🏻FMEA in the Automotive Industry Action Group (AIAG) FMEA-4 format.

👉🏻Basic Analysis Procedure for FMEA or FMECA

👉🏻The basic steps for performing an FMEA/FMECA analysis include:

☄Assemble the team ☄Establish the ground rules☄Gather and review relevant information☄Identify the item(s) or process(es) to be analyzed☄Identify the function(s), failure(s), effect(s), cause(s) and control(s) for each item or process to be analyzed👉🏻Evaluate the risk associated with the issues identified by the analysis👉🏻Prioritize and assign corrective actions👉🏻Perform corrective actions and re-evaluate risk👉🏻Distribute, review and update the analysis, as appropriate.

👉🏻Risk Evaluation Methods

👉🏻A typical FMEA incorporates some method to evaluate the risk associated with the potential problems identified through the analysis👉🏻The two most common methods, Risk Priority Numbers and Criticality Analysis, are described next.

👉🏻Risk Priority Numbers

👉🏻To use the Risk Priority Number (RPN) method to assess risk, the analysis team must:

👉🏻Rate the severity of each effect of failure👉🏻Rate the likelihood of occurrence for each cause of failure👉🏻Rate the likelihood of prior detection for each cause of failure (i.e. the likelihood of detecting the problem before it reaches the end user or customer)👉🏻Calculate the RPN by obtaining the product of the three ratings:

👉🏻RPN = Severity x Occurrence x Detection

👉🏻The RPN can then be used to compare issues within the analysis and to prioritize problems for corrective action.

👉🏻Criticality Analysis

👇🏼The MIL-STD-1629A document describes two types of criticality analysis: quantitative and qualitative👉🏻To use the quantitative criticality analysis method, the analysis team must:

👉🏻Define the reliability/unreliability for each item, at a given operating time.Identify the portion of the items unreliability that can be attributed to each potential failure mode👉🏻Rate the probability of loss (or severity) that will result from each failure mode that may occur👉🏻Calculate the criticality for each potential failure mode by obtaining the product of the three factors:

👉🏻Mode Criticality = Item Unreliability x Mode Ratio of Unreliability x Probability of Loss

👉🏻Calculate the criticality for each item by obtaining the sum of the criticalities for each failure mode that has been identified for the item.

👉🏻Item Criticality = SUM of Mode Criticalities

👉🏻To use the qualitative criticality analysis method to evaluate risk and prioritize corrective actions, the analysis team must:

👉🏻Rate the severity of the potential effects of failure👉🏻Rate the likelihood of occurrence for each potential failure mode👉🏻Compare failure modes via a Criticality Matrix, which identifies severity on the horizontal axis and occurrence on the vertical axis.

👉🏻Applications and Benefits?

👉🏻👇🏼The FMEA / FMECA analysis procedure is a tool that has been adapted in many different ways for many different purposes. 👉🏻It can contribute to improved designs for products and processes, resulting in higher reliability, better quality, increased safety, enhanced customer satisfaction and reduced costs👉🏻 The tool can also be used to establish and optimize maintenance plans for repairable systems and/or contribute to control plans and other quality assurance procedures👉🏻It provides a knowledge base of failure mode and corrective action information that can be used as a resource in future troubleshooting efforts and as a training tool for new engineers. In addition, an FMEA or FMECA is often required to comply with safety and quality requirements, such as ISO 9001, QS 9000, ISO/TS 16949, Six Sigma, FDA Good Manufacturing Practices (GMPs), Process Safety Management Act (PSM), etc.
👉🏻software facilitates analysis, data management and reporting for failure mode and effects analysis (FMEA) and failure modes, effects and criticality analysis (FMECA)👉🏻The software supports all major standards (AIAG FMEA-3, J1739, ARP5580, MIL-STD-1629A, etc.) and provides extensive customization capabilities for analysis and reporting, allowing you to configure the software to meet your organization's specific analysis and reporting procedures for all types of FMEA / FMECA (its not exact answer may be but it will help to understanding the concept) 

Why Sampling Plan is SQRT n+1 or √n+1 for Pharmaceuticals?

The sampling formula SQRT n+1 in pharmaceuticals and its recommendations in various guidelines.
Quality of pharmaceutical products majorly depends upon the sampling of the excipients and the active pharmaceutical ingredients. Proper sampling can give us confidence in our analysis.
 In other words we can say – sampling is a starting process but is has its importance.
Number of containers to be sampled is an interesting part of the raw material sampling because it we receive 5000 containers of an excipent then it shall be very difficult to sample all containers and it is difficult too to analyze the thousands of samples. In such cases sampling plans are used to reduce the sampling and analysis of large number of containers. Generally in pharmaceuticals,  SQRT (n+1) or √n+1 formula is used to determine the number of containers to be sampled. Where n is the number of containers received. This formula is used to reduce the sampling of the large number of containers of the excipents. Some companies have their own limitations as if containers are 10 or less, all containers shall be sampled.
WHO suggests 3 formulae of sampling for pharmaceutical ingredients in Technical Report Series TRS-929 - Annex 4, “WHO Guidelines for sampling of pharmaceutical products and related materials”.

 n-plan: This plan is used when the material is uniform and supplier is recognised and reliable. Sample can be taken from any part of the container. Samples are taken by using the formula n=1+√N. Sampling units are selected randomly and all containers shall be sampled if those are four or less in number.

p-plan: Samples are taken using this plan only when material is received from the reliable sources and identification of material is being done. Sampling is done by using the formula p=0.4√N and samples are collected in separate sample containers.

r-plan: r-plan is used when the material is suspicious and received from the unknown source. Sampling is done using the formula r=1.5√N. It gives the more number of samples than the n-plan to build the confidence level.

All samples are collected separately and transferred to quality control laboratory for identification. If sample passes the identification test; sample is analyzed for the assay.
Department of Human Health Services, Food and Drug Administration (FDA) clearly writes in 21 CFR Part 111 Docket No. 2007N–0186 that there are a lot of sampling plans but we use SQRT n+1 and also suggests to sample 4 from 10 containers, 11 from 100 containers and 32 from 1000 containers.
Therapeutic Goods Administration, Australia (TGA) states in its guideline “Sampling and testing of complementary medicines” that formula √n+1 can be used for the sampling of the excipents and sampling of the active material can be reduced.
Therefore, √n+1 is a widely accepted formula for the determination of the containers to sampled in pharmaceuticals and all major regulatory agencies recommend the same.