Design For Safety Equipment and design

Design for safety

System safety

System Safety is the application of engineering and management principles, criteria, and techniques to optimize all aspects of safety within the constraints of operational effectiveness, time, and cost throughout all phases of the system life cycle. It is a planned, disciplined and systematic approach to preventing or reducing accidents throughout the lifecycle of a system

Primary concern is the management of risks through:

  • Risk identification, evaluation, elimination & control through analysis, design & management

History of system safety

Design Safety arose in the 1950s after dissatisfaction with the fly-fix-fly approach to safety. Design Safety was first adopted by the US Air Force. It led to the development of mil-std-882 Standard Practice for System Safety (v1 1960s). The basic concept of System was rather than assigning a safety engineer to demonstrate that a design is safe, safety considerations were to be integrated from the design phase of the project.

Founding principles

Safety should be designed in

  • Critical reviews of the system design identify hazards that can be controlled by modifying the design
  • Modifications are most readily accepted during the early stages of design, development, and test
  • Previous design deficiencies can be corrected to prevent their recurrence

Inherent safety requires both engineering and management techniques to control the hazards of a system

  • A safety program must be planned and implemented such that safety analyses are integrated with other factors that impact management decisions

Safety requirements must be consistent with other program or design requirements

  • The evolution of a system design is a series of tradeoffs among competing disciplines to optimize relative contributions
  • Safety competes with other disciplines; it does not override them

The main principles of Safe design are:

  • Inherent safety
  • Safety factors
  • Multiple independent safety barriers

Inherently safe design 

Inherent: belonging to the very nature of the person/thing (inseparable). It is recommended that Inherent safe design should be the first step in safety engineering. Change the process to eliminate hazards, rather than accepting the hazards and developing add-on features to control them, unlike engineered features, inherent safety cannot be compromised.

Minimize inherent dangers as far as possible by considering the following:

  • Potential hazards are excluded rather than just enclosed or managed
  • Replace dangerous substances or reactions by less dangerous ones (instead of encapsulating the process)
  • Use fireproof materials instead of flammable ones (better than using flammable materials but keeping temperatures low)
  • Perform reactions at low temperatures & pressures instead of building resistant vessels

Safety Factors

Factors of safety (FoS), also known as safety factor (SF), is a term describing the load carrying capacity of a system beyond the expected or actual loads. Essentially, the factor of safety is how much stronger the system is than it usually needs to be for an intended load. Safety factors are often calculated using detailed analysis because comprehensive testing is impractical on many projects, such as bridges and buildings, but the structure’s ability to carry load must be determined to a reasonable accuracy.

When the material used is under strength, factor of safety covers uncertainties in material strength. It covers poor workmanship. It also covers unexpected behavior of the structure and natural disasters. Stresses are produced which may be very high. Factor of safety may take care of these loads during construction. Presence of residual stresses and stress concentrations beyond the level theoretically expected.

Multiple Independent Safety Barriers

Safety barriers are arranged in chains. The aim is to make each barrier independent of its predecessors so that if the first fails, then the second is still intact, etc. Typically, the first barriers are measures to prevent an accident, after which follow barriers that limit the consequences of an accident, and, finally, rescue services as the last resort.

The basic idea behind multiple barriers is that even if the first barrier is well constructed, it may fail, due to unforeseen reason, and that the second barrier should then provide protection. The major problem in the construction of safety barriers is how to make them as independent of each other as possible. If two or more barriers are sensitive to the same type of impact, then one and the same destructive force can get rid of all of them in one swoop.

These three principles of engineering safety – inherent safety, safety factors, and multiple barriers are quite different in nature, but they have one important trait in common. They all aim at protecting us not only against risks that can be assigned meaningful probability estimates, but also against dangers that cannot be probabilized, such as the possibility that some unforeseen even triggers a hazard that is seemingly under control. It remains, however, to investigate more in detail the principles underlying safety engineering and, not least, to clarify how they relate to other principles of engineering design.



Continuous Distillation Column Design

Procedure for Continuous Distillation Column Design

Distillation is used to separate components in a feed mixture based upon their relative boiling points. A simple, continuous distillation column can make the separation between two components into two product streams. In multi-component systems, the two main components to be separated are designated as the light and heavy keys. The light key is the more volatile component in greater purity in the top product stream, and the heavy key is the less volatile component in greater purity in the bottom product stream.

Vapor-Liquid Equilibrium

The starting point upon which all column design is based is to accurately determine the relative volatility of the key components to be separated. Using a mass and energy balance simulation program. The user must set up the basis of the simulation by selecting an appropriate fluid package and the components present in the feed. Activity coefficients, estimated by the program or provided by the user, are used to relate non-ideal component interactions.

Column Operating Objectives

The first step in column design is specifying the column operating objectives. These are defined by a primary product composition and an optimal recovery of the product from the waste, recycle or less important by-product stream. These specifications should be in terms of the heavy key impurity in the top stream and the light key impurity in the bottom stream.

Operating Pressure

Once the top and bottom stream compositions are specified, the dew point of the top stream and the boiling point of the bottom stream may be determined at various pressures. An operating pressure should be selected that allows acceptable temperature differences between available utilities because the overhead vapor must be condensed and the bottom liquid reboiled.

When possible, atmospheric or pressure operation of the column is preferred in order to avoid requiring a vacuum system. However, another consideration is component heat sensitivity, which may require lower pressure operation to avoid fouling, product discoloration or decomposition. Often the relative volatility is also improved at lower pressures.

R/Dmin & Nmin and Feed Stage Estimation

Using the simulation program, shortcut procedures based upon total reflux operation allow the minimum reflux ratio (R/Dmin) and minimum number of ideal separation stages (Nmin) to be determined. Using an actual reflux ratio of 1.2 times the minimum reflux ratio will allow an optimal number of stages to be estimated as well as an appropriate feed stage.

Rigorous simulation of the distillation at a given feed rate and composition may now be accomplished by specifying the following: top and bottom product compositions, number of stages, feed stage, and top and bottom pressure.

Parametric cases of this simulation should be used to verify the estimated number of stages and feed location. Add and subtract stages from both the stripping and rectifying section of the column. Do this until the required reflux ratio becomes approximately 1.2 times the minimum reflux ratio, or the trade off between utility usage and the number of stages appears optimal for the specific column. As more total stages are used, the required reboiler duty will decrease until there are diminishing returns.

Diameter and Height of the Column

At this point, the distillation process is well defined, leaving the column diameter and height to be determined. The chosen design case from the simulation program provides the internal liquid and vapor flows and their physical properties for every stage of the column. The column diameter is chosen to provide an acceptable superficial vapor velocity, or “Fs factor”. This is defined as vapor velocity (ft/sec) times square root of vapor density (lb/ft3), and liquid loading defined as volumetric flow rate (gal/min), divided by the cross sectional area of the column (ft2). The column internals can be chosen as either trays or packing. Trayed columns must avoid flooding, weeping and downcomer backup. Packed columns must avoid flooding, minimum surface wetting and mal-distribution.

Project managers should understand and determine these five key design elements for the projects success. Cost, chemical interactions and equipment needs change in a non-linear fashion, as increased output is required. Qualified engineers should consider these critical steps for distillation column design.

Automated manufacturing Practice

Good Automated Manufacturing Practice for Pharmaceutical Industries

The Good Automated Manufacturing Practice (GAMP) Forum was founded in 1991 by pharmaceutical industry professionals in the United Kingdom to address the industry’s need to improve comprehension and evolving expectations of regulatory agencies in Europe. The organization also sought to promote understanding of how computer systems validation should be conducted in the pharmaceutical industry.

GAMP rapidly became influential throughout countries as the quality of its work was recognized internationally. Over time, GAMP has become the acknowledged expert body for addressing issues of computer system validation.

GAMP’s guidance approach defines a set of industry best practices to enable compliance to all current regulatory expectations. More than simply a strict compliance standard, GAMP is a guideline for life sciences companies to use for their own quality procedures. As a result, it can be tailored to a number of computer system types.

Computer system validation following GAMP guidelines requires users and suppliers to work together so that responsibilities regarding the validation process are understood. For users, GAMP provides a documented assurance that a system is appropriate for the intended use before it goes live. Suppliers can use GAMP to test for avoidable defects in the supplied system to ensure quality product leaves the facility.

The GAMP framework addresses how systems are validated and documented. Companies do not need to follow the same set of procedures and processes of a GAMP framework to achieve validation and qualification levels that satisfy inspectors. Instead, GAMP examines the systems development lifecycle of an automated system to identify issues of validation, compliance and documentation.

As a voluntary program, GAMP offers both challenges and benefits. The top three challenges in implementing GAMP are establishing procedural control, handling management and change control, and finding an acceptable standard among the existing variations.

Establishing procedural control is a challenge in using GAMP guidelines because new frameworks may be necessary to gauge the validity of systems. Most pharmaceutical companies have already established a baseline that adheres to standards and regulations that exist today, but they may not have a procedure to check the processes that are in place. This could cause resistance among software developers who may prefer not to work within the confines of specifications and procedures developed by others. Specifications and procedures developed by previous software developers may hinder ways to adjust computer systems, but varying interpretations of GAMP guidelines allow for multiple solutions.

Another hurdle is change control. In the development or modification of computer systems, companies with even the highest of standards can suffer setbacks along the systems development lifecycle. Sometimes minor tweaks by the software programmer may cause breakdowns after validation changes have been implemented. Internal processes and procedures must be established to guard against these occurrences.

Effective documentation management is fundamental for compliance. Any inaccuracies or missing information renders all other efforts moot. Moreover, implementing a formal document management application may be cost-prohibitive for some organizations. Some companies simply use what’s in the GAMP checklists to evaluate their systems. Today’s environment demands a thorough process to show validation.

The benefits of utilizing the GAMP approach for both users and suppliers include:

  • Improved understanding of the subject with the introduction of common terminology
  • Reduced cost and time to achieve compliant systems
  • Reduced time and resources for revalidation or regression testing and remediation
  • Reduced cost of qualification
  • Enhanced compliance with regulatory expectations
  • Established responsibility for all involved parties

When the FDA introduced its current Good Manufacturing Practices (cGMP) for the 21st century initiative, companies shifted their approach to validation. Formerly, they only had to heed a set of rules that accounted for every piece of equipment that was used. Now they can take a risk-based approach to validation by addressing safety, efficacy and quality in the product considerations. This enables the industry to place its investments where it makes the most sense. The onus ultimately falls on manufacturers to accept greater responsibility to validate their systems having the attendant benefits of cost and time to market savings.

GAMP helps provide a quality product from the manufacturer, and helps to limit the pharmaceutical industry’s culpability by ensuring proper steps were placed to deliver a quality product through validated systems. By incorporating input from the full spectrum of stakeholders, fine-tuning and further development of the process is geared towards benefiting the life sciences industry and the general consumer market.

The tools exist for companies to take the steps needed to reap the benefits of validation. Understanding an early adoption of GAMP can increase a company’s competitive position, especially with the implementation of new technologies. By staying aware of technological innovations, companies are able to increase efficiency, minimize risks and reduce costs.

Fire Protection and Safety

Irrespective of its occupancy status, a fire can happen at any time and any place.
Fire has the potential to cause harm to its occupants and severe damage to property. Fire doesn’t only interrupt the whole process of manufacturing and production but also can cause major damage to the building and plant. Much work will be required in order to restore the entire production process.

Successful prevention of fire depends solely on the management who must survey the operation of the business and determine where the loss potential lies.

Inadequately maintained machines can be fire prone. The overheating of bearing, due to insufficient lubrication or the presence of dust, and heat caused by friction are common causes of fire. Frequent inspection and regular maintenance will reduce risk and make the general tidiness of premises easier to achieve.

Major fires start in storage area and warehouses than production areas. Poorly stored goods, even though they are not flammable, may help to spread fire and hinder fire fighters gaining access to the seat of the fire or reduce the effectiveness of sprinkler systems. Goods tidily stored with gangways may help to inhibit the spread of fire.

Fire Safety Audit

Fire has been rated as the 5th largest risk in the Indian Industry. Electrical defaults are the major causes of fire in India. Fire Safety Audit is found to be an effective tool for assessing fire Safety standards of an organization. In other words, it is aimed to assess the building for compliance with the National Building Code of India, relevant Indian Standards and the legislations enacted by State Governments and Local Bodies, on fire prevention, fire protection and life safety measures.

Though fire safety audit is found to be an effective tool for assessing fire safety standards of an occupancy, there is no clear cut provisions in any of the safety legislations in India, regarding the scope, objective, methodology and periodicity of a fire safety audit. Therefore, Fire Safety Audit should be made mandatory for all over India and the work should be entrusted to independent agencies, which have expertise in it. It is reasonable to have a fire safety audit in every year.

Clean agent suppression systems

Clean agent fire suppression systems make the use of inert gases and chemicals in extinguishing a fire.They are also known as gaseous fire suppression. In these systems, fire is suppressed manually or automatically by reducing heat rather than reducing oxygen, reducing fuel or preventing the chain reaction effect of fire. These systems work on a total flooding principle where the agent is applied in a three dimensional method within the enclosed space to deliver a concentrated, highly focused dose of fire suppression.

Clean agent systems are able to suppress fires without causing additional damage unlike water. This drastically reduces the costs incurred for repairs and replacements. This makes these systems the fire suppression systems of choice for commercial and public enterprises that want fast, effective fire suppression that minimizes damage to structures, electronics and other assets.

The agents are non-toxic, they cause no breathing problems for people and won’t obscure vision in an emergency situation.

Automatic Sprinkler Systems

Sprinkler systems are among the most useful tools in firefighting. Automatic sprinklers often are one of the most important fire protection options. The successful application of sprinklers is dependent upon careful design and installation of high quality components by capable engineers and contractors.

A sprinkler system must be installed in compliance with the building’s need. Wet pipe systems offer the greatest degree of reliability and are the most appropriate system type for most heritage fire risks. With the exception of spaces subject to freezing conditions, dry pipe systems do not offer advantages over wet pipe systems in heritage buildings. Preaction sprinkler systems are beneficial in areas of highest water sensitivity. Their success is dependent upon selection of proper suppression and detection components and management’s commitment to properly maintain systems. Water mist represents a very promising alternative to gaseous agent systems.

In India, although there are many rules and regulations, codes and standards related to fire safety they are seldom followed. Laxity in following fire safety measures causes major fires in many buildings. Proper attention must be paid to minimize fire loss because ultimately the community at large has to bear all the losses. There exists large number of different types of firefighting equipment and suppression systems to suit specific requirements. The use of smoke detectors, fire alarms, automatic sprinklers, water mist systems, clean agent suppression system should be encouraged. Above all the success of fire prevention and fire protection mainly depend upon the active co-operation from all personnel.

Signs your construction project is headed towards failure

Chemical and Pharmaceutical Plant Construction projects involve high risks and heavy investments. Sometimes a single risk can manage to blowout your project. At other times, a combination of risks will be the reason for your project failure. One or multiple, either can prove to be fatal for the project and company. It is critical to identify project failure sooner and devise solutions before the risks escalate.

Here’s a list of obstacles that could lead to project failure and solutions on how to overcome them.

  1. Schedule overdue – Scheduling is the first step one takes when working on any project. For any successful project, scheduling needs to be on track. Once the train is off track, your project is bound to suffer. Project leaders must ensure that every schedule is being followed devotedly. In case work deviates from the track immediate measures must be taken to cover for lost time.
  2. Team mismanagement – For a project, the team comprises of experts from varied fields. Architects, maintenance engineers, owners, electricians, plumbers etc. are few of the people that work together on the project. Disagreements and conflicting ideas lead to setbacks in your project. The most effective way to handle these holdups is to evaluate ideas and execute the strategies that are most effective.Project management services should be implemented after thorough analysis.
  3. Budget – While being on schedule is important, managing to be on the stipulated budget is imperative. Spending over the budget can lead to major dents in the financial plan. Project leaders must always be on their toes especially when the budget is skirting towards the warning line.Costs for construction projects are high and involve a lot of risks.
  4. Poor communication – Any project is likely to fail with poor communication. Generally, lower level employees are hesitant to report to upper level management leading to delay in project work. Upper level managers consider it irrelevant to inform employees at the lower level. Communication amongst all levels is vital to ensure that the project is functioning smoothly. The project leader should act as the communicator link between all levels.
  5. Inconsistent management – Project leaders must avoid inconsistency in decision making. When minor plans keep changing course, it will be difficult to meet the goals in time. Leaders have to be firm in their decision-making and must have a foresight for the future. Project management services should be implemented to ensure the success of a construction project.

Every project, no matter how big or small, will face problems at every stage. Good leadership and communication is the glue that will stick your project together in times of failure. A healthy working environment for the employees and strategic approach aid in the long run.
Panorama provides complete project management services right from planning to execution. Every step is supervised under the watchful eyes of experts in the field. With Panorama, your construction project is far from the trenches of failure.