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• Hotels & Air Conditioning: Some aspects
  by S.K.Murthy
  Mumbai, the commercial capital of India is in need of hotel rooms. With several new hotels under construction or in the planning stage, this article presents some aspects of HVAC systems in hotels.
  
• Opportunities For Energy Conservation In RAC
  by Dr.Milind Rane
  Reducing the effects of increasing energy costs, inadequate electricity generation and distribution infrastructure and increasing demand for refrigeration and air conditioning (RAC) are the problems, which can be reduced by the HVACR community.
  
• Electrical Switchgear And Controlgear
  by Venkat Iyer
  The HVACR engineer needs to be familiar with basics of switchgear and controlgear. How and where to use these devices is explained to the ACR engineer in this article.
  

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• Air Conditioning of Pharmaceutical Plants
  by G.S.Saraiya
  This article explains why manufacture of pharmaceuticals must be carried out in carefully designed facilities with a clean aseptic environment, controlled relative humidity and comfortable temperature.
• Trouble Shooting ACR Systems
  by Krishna V.Jog
  An experienced engineer recalls some of the problem jobs he was involved in sorting out, the importance of field visits and the need to probe all aspects of equipment selection and design before arriving at a conclusion.
• Capacity and Performance Testing of Packaged Air Conditioners
  by D.Ravindra
  With increasing competition manufacturers of packaged and split air conditioners need to install test facilities to ensure their units perform as specified - no less but may be more.
• An Overview of Cold Storage Practise in India
  by Arvind Surange
  Changes that have occurred in the design and installation of cold storages in India over the last two decades, the increasing popularity of PUF prefab panel construction and why this is not more commonly used is explained.
• Evaporative Pre-cooling for Air Cooled Condensers
  by Surendra H.Shah
  A simple idea, imaginatively applied and how it can save both in initial and operating cost.
  

• Central vs Floor-by-Floor AC for Office Buildings
  By Rita Kriplani
  Pros and cons of central chilled water as well as packaged air conditioning systems are explained and main aspects of each type discussed at length. That each type has a place of its own and often both types are required in the same building is clearly brought out.
• DX Air Conditioning for Office Buildings
  by M.H.Lulla
  The basics of direct refrigerant expansion and the advantages of such a system, both central and unitary, for office air conditioning are discussed in detail with examples of buildings using such systems.
• VAV Systems for Office Buildings
  by Rob Moult
  While variable air volume systems have been around for a long time in the USA they are slowly being accepted in India for the new breed of office buildings being planned and constructed in all major cities.
• Ducting - The New Frontier
  by Pratap Gidwani, Ramesh Lalvani and Jagdish Gharote
  What factory made ductwork can accomplish and its advantages over hand made ductwork is explained by entrepreneur and owner of India's first automated duct fabrication shop.
• An Industrial Designer's Viewpoint
  by Sunil Malhotra
  How can an industrial designer contribute to a better air conditioner or packaged chiller? Is there scope for his involvement in our industry? Malhotra explains how and the editors photographs show the need for better designs.
  

• Fire and Smoke Dampers
  By Arvind Desai
  Application guidelines, construction standards, testing facilities, installation practices and actuator selection are explained in this article in an effort to initiate action by Fire Department to codify best practices into a detailed standard.
• Stairwell Pressurization
  By Pranab K Chowdhury
  The principles and practice of smoke control are explained in detail in an effort to demystify the subject and emphasize the importance of stairwell pressurization in tall buildings.
• Control Strategies for VAV Air Handling Units
  By Rob Moult
  This is the second in a series of articles to help the design professional familiar with constant air volume air conditioning to understand VAV systems better.
• Use of Ammonia for Air Conditioning Applications
  By Ramesh Paranjpey
  Ammonia has been used for refrigeration applications in food preservation for a long time but its use in air conditioning plants is fairly new. Why its use in such applications should be increased is well brought out in this article.
• Thermodynamic Properties of Air Water Mixtures (-100 to 100 deg C and 50 to 5000 kPa)
  By B. Jayaraman
  A compilation of formulae and data used to construct psychrometric charts for absolute pressures of 50 kPa, 101.325 kPa (14.7 kPa) and 1000 kPa that can be useful for vacuum drying and compressed air drying applications.
  

• Refrigeration for Ice Cream Manufacturing
  By Dilip Sarda
  Ice cream involves refrigeration at many stages - in its manufacturing, hardening, transporting, storing and finally retailing. The author takes you through the various stages and shows how refrigeration loads are calculated.
• Hermetic Motors
  By D. Ravindra
  Commonly used in hermetic and semi-hermetic compressors, readers will learn how hermetic motors differ from their air-cooled cousins - the standard motor.
• Control of Cooling - only VAV boxes
  By Rob Moult
  Third in a series of articles to help the design professional familiar with constant air volume air conditioning to understand VAV systems better.
• Variable volume Pumping Fundamentals
  By Kennath R. Luther
  Primary-secondary pumping used in large, high pressure drop distribution systems such as airports, campuses, large research institutes (BARC Mumbai or CAT Indore) help cut pumping costs in HVAC systems.
  
  

• Inlet Air cooling for Gas turbines
  By Arun Dharap and Anil Ghanwat
  Captive power plants for large industrial undertakings frequently use natural gas or naphtha for power generation. Air required for combustion in the turbine, if cooled by refrigeration can help improve efficiency. Evaluating and selecting the right type of refrigerating plant is the topic of this article by engineers with practical application experience on the subject.
• Increasing Productivity in HVAC Layout Work
  By N. S. Rao
  HVAC system designers and contractors can increasingly rely on computerization and smarter software to speed up design and fabrication of ductwork, calculations of sheet metal area required and many other aspects of HVAC system design.
• Indoor Air Quality Control of VAV AHUs.
  By Rob Moult
  Fourth in a series of articles to help the design professional familiar with constant volume air conditioning to understand VAV systems better. Today, IAQ is a very important issue that is a part of the design of any HVAC system.
• The Need for Balancing Valves in a Chilled Water System
  By Robert Petitjean
  Balancing valves are an essential part of any HVAC chilled water distribution system and help the eventual user realize the full potential of a well designed, properly installed and carefully selected system that satisfies the comfort need of the occupants in all areas.
• Applying Variable Volume Pumping
  By Kenneth R. Luther
  This is a continuation of "Variable Volume Pumping fundamentals" in the July-Sept 1999 issue by the same author. Primary - secondary pumping helps cut pumping costs in large HVAC chilled water distribution systems.
  
  

• Effect of Solar Shading on Windows
  By Rajeev Kakkar
  Solar heat gain from windows can be effectively reduced by external shading devices such as chajjas and vertical fins. The equations for calculating the shading effect by such devices can be quite complex. This article attempts to simplify such calculations for peak heat gain during May at 4 pm for latitudes 10ºN, 20ºN and 30ºN which cover almost the entire Indian sub-continent.
• Eurovent Certification of Air-Cooled Heat Exchangers
  By David B. Young
  The author, based in England, explains the confusion arising out of different interpretations of the term"Temperature Difference" (TD) as applied to Unit Coolers used in cold storages in Europe and how the problems have been resolved amongst manufacturers with a common system of certification.
• Hydronic Balancing - a necessity for Good Control and Improved HVAC Performance
  By Robert Petitjean
  Indicating design flows on drawings is not sufficient to obtain such flows in actual practice. Installing balancing valves and carrying out hydronic balancing enables the required flows to be obtained, compensating and justifying the investments made.
  

• Design and Application of Small Screw Compressors - Part 1
  by Hermann Renz, Bitzer Kuhlmaschinenbau Gmbh
  Small, highly efficient screw compressors are challenging reciprocating machines on their traditional home turf in commercial and light industrial markets.
  
• Scroll Compressors for AC & R Applications
  By Danfoss Industries Pvt. Ltd.
  Hermetic scrolls are slowly replacing hermetic recips in residential and commercial split air conditioners and packaged chillers. Find out why.
• Use of Suction - Gas Cooled and Direct Air-Cooled Semi Hermetic Compressors
  By Stephan Engelking, Bock GmbH & Co.
  The new design direct air-cooled compressor finds application at low evaporating temperatures with low compressor discharge temperatures.
• Semi-Hermetic Reciprocating Compressors
  By Shankar P. Deshpande & Manoj Kumar Venugopal, Kirloskar Copeland Ltd.
  This workhorse of the industry is gaining acceptance over the open type compressor as reliable hermetic motors are now being manufactured in India.
• Alternatives for R-22 in Split System Air Conditioners
  By Lawrence Chin & Mark Spatz
  With R-22 eventually being phased out under the Montreal Protocol alternative refrigerants must be tried and tested. Here are some answers.
• Hydronic Balancing and stabilization of the Differential Pressures
  By Robert Petitjean
  

• Selection, Design and Fabrication of Quieter Fans for HVAC Systems
  By Dr. M.L. Munjal
  The major source of noise in heating, ventilating and air conditioning systems are fans and blowers of air handling units. Proper selection and application can help eliminate this problem. Selection criteria for different types of fans and use of sound attenuators is explained.
• Dust Control in Pharma Industries
  By G.S. Saraiya
  Tablet manufacturing presents the biggest challenge to the ventilation engineer in controlling dust and safeguarding worker's health,. Design of duct extraction systems, hood design and calculation of exhaust air volumes are all documented.
• Design and Application of Small Screw Compressors - Part 2
  By Hermann Renz, Bitzer Kuhlmaschinenbau Gmbh
  Parallel operation of small screw compressors and comparison of performance/operating costs with reciprocating systems is shown. Concluding part of a two part series.
• Flow Compatibility at System Interfaces
  By Robert Petitjean
  Production of hot/chilled water and its distribution in heating/cooling coils must be balanced to avoid oversizing. How balancing valves can help is explained in this last article of a three part series.
• Practical Guide - Low Temperature Refrigeration
  By Rudy Stegmann P.E
  An overview of the design problems associated with low temperature refrigeration systems in the range of - 50 ºC to - 100ºC (-58ºF to - 148ºF)
  
  

• High-Performance Heat-Transfer Tubes for AC&R Applications
  By D. Ravindra
  Reasons why such tubes were developed, the manner in which they perform, the variety available, manufacturer's names and in what type of AC&R heat exchangers they are best used in, are all explained in this practical article.
• Integrating Chillers and Building Automation Systems
  By Richard Robertson and Rob Moult
  This article attempts to describe the type of information that can be shared between chillers and the BAS and the benefits to the building manager if this integration capability is fully implemented.
• Stainless Steel Tube Coils for Use with Ammonia
  By David B. Young
  The widespread use of SS tube coils in Ammonia refrigeration systems for cold storages and blast freezes in Europe and its advantages over traditional galvanized steel coils used in India are clearly explained by the Author who has worked in England for long years.
• An Integrated Approach to Cold Store Loading Bay Design
  By Kjell Erlandson
  The analytical approach to loading bay design and how it can help reduce operating costs and problems in modern cold storages will be useful to owners of existing cold stores as well as designers of new cold stores in India.
  

• Air Conditioning of Leisure Centres
  By Rohit Uchil
  Bowling Alleys, Fast Food outlets, Shopping Centre and similar facilities are becoming increasingly common and designing their air conditioning systems calls for practical experience and background information which this article attempts to provide.
• Heat Pump for Domestic and Light Commercial Markets
  By Milind V. Rane and Avijit Das Gupta
  Widely used in North America for domestic and light commercial applications, heat pumps are relatively new to India. They provide a low cost source of hot water along with air conditioning and by modifying a standard room air conditioner; the heat pump can come within the reach of many home-owners.
• Indoor Air Quality (IAQ) - Issues at Stake
  By Deepak Pahwa
  What is IAQ why we must focus on it and how we can reduce or control the contaminants in the air that we breathe, whether at home or in an office are clearly explained by the author.
• A Primer on Pumps for HVAC
  By Dilip Datey
  Pumps are often taken for granted and many engineers are not familiar with different types available basic pump laws and how energy can be saved by proper selection.
• Ammonia Low Pressure Recievers
  By S.F. Pearson
  This reprint of a paper presented to the Institute of Refrigeration Engineers in the U.K., explains the working of compact Ammonia refrigeration system using a low pressure reciever & how successful its application has been for cold stores in the U.K.
  

• Low Energy 100%-Outside-Air Dryer
  By Surendra Shah, Yusuf Bhetasiwala and Dharmesh Mehta
  There are many ways of drying air for different applications. This article covers several commonly used methods and presents a different approach which is claimed to be extremely energy efficient. Readings from an actual installation are presented.
• A New Design Rotary Compressor for Mobile AC & R Applications
  By Hirak Mukherjee
  Thee are several types of rotary compressors for mobile applications. The OVR type which was partly developed in India, is currently under manufacture in Pune for the world market. Unique features of the OVR compressor and it's comparative performance with other brands in tests carried out by an independent company are furnished.
• Engineered Filter Frames for Clean Rooms
  By S.K. Jaiswal and P.B. Kulkarni
  As a rule, filter frames for clean room application do not receive the care in design and manufacture that they deserve. The authors explain then view point, show the design improvements possible and furnish test readings from a prototype clean room tent equipped with their engineered frame.
• Health-Care IAQ : Guidance for Infection Control
  By Andrew J. Streifel
  Making IAQ a top priority in the health-care industry starts with building design, Infection-Control risk assessment (ICRA) is a tool that does exactly that. ICRA, which is outlined in this article, helps identify the areas that are at greatest risk of airborne infectious agents.
• Saving Energy in Refrigerated Warehouses
  By Jianyi Zhang and Eckhard A. Groll
  Most engineers may not consider the possibility of reducing electricity bills for refrigerated warehouses by improving the efficiency of the electric systems of the plants. However, improving the power factor is an important method for increased efficiency.
  

• The Use of Variable Frequency Drives in Existing HVAC Installations
  By A. Bhaduri
  How a VFD works and how it can save on energy bills in HVAC systems is clear explained. Existing HVAC systems, installed during the days when energy was cheap and imported controls were very expensive and difficult to import, are the obvious target for maximum power savings.
• VSD for Chillers
  By Seemant Sharma
  VSDs on centrifugal chillers are new to the Indian market but very well accepted internationally. Chillers with a variable speed drive and inlet guide vane control can together achieve optimum chiller performance.
• Air-Cooled Condensers
  By Ravindra
  As water becomes scarcer and cities clamp down on usage for air conditioning plants, air cooled condensers are taking over. The fundamentals of design, selection, manufacturing, capacity control and maintenance are among the various items explained by the author.
• Evaluation of Overall Chiller Performance Characteristics
  By M. Nadeem
  With the variety of packaged chillers available today, the end user or consultant has a difficult job to perform in deciding which type to specify for his HVAC project. Here is one consultant who guides you through the various factory involved in evaluating chiller performance, particularly for a hotel project. The methodology can be applied to any other type of building as well.
• New Developments Industrial Refrigeration
  By Andy Pearson
  Sitting and working on the other side of the world, the author recounts his company's experience with Carbon Dioxide as a refrigerant in a large, low temperature installation in a food plant. The advantages and disadvantages of CO2 over Ammonia which is the most commonly used refrigerant in industrial refrigeration in Europe today, are explained.
  

• Air Conditioning of Clean Rooms for Pharmaceutical Plants
  By Pradeep Shankar
  From definition, classification and type of clean rooms the article leads you through to building design, are conditioning system design, air handling system design, duct design, air flow patterns and air filter selection
• Designing Clean Room HVAC Systems
  By Raymond K. Schneider
  Written by a clean room consultant, the author simplifies the presentation by dividing clean rooms into three levels - stringent, intermediate and less stringent. The concept of filter efficiency by the MPPS method is brought out and practical tips given in air flow design and makeup air.
• Sustenance of Clean Room Conditions
  By Rashmi Nagabhushan
  Proper design and installation of a clean room facility is an important first step but equally important is staff training in clean-work habits, strict discipline and timely maintenance, without which design conditions can deteriorate rapidly. Several case histories of failed installations are brought out.
• One Building Experiences Three Types of Chillers
  By M.H. Lulla
  A forty year old office building installs a new set of screw chillers with allied pump work with only one working day shutdown of cooling. Advance planning and a dedicated team of workers helps to achieve results cutting down inconvenience and saving energy costs.
• Impact of Cooling Tower Blade Modification on Energy Consumption
  By P. Gupta
  Written by an expert on maintenance responsible for 95% uptime of the Nuclear Science Centre facility, the article explains how changing the cooling tower fan blades not only saved on energy consumption but also on maintenance cost.
  

• Air Conditioning Design for Data Processing Centres
  By MarkSimpson and Atul Mathur
  Air conditioning system design for DPCs and the increasingly common requirements for Six Sigma system availability is creating a demand for greater engineering sophistication in he total design of the facility.
• Precision or Comfort Air Conditioning
  By Stulz GmbH
  In simple language, the article explains why a comfort air conditioner is unsuitable for removing the high sensible heat generated in a telecom or server room.
• Underfloor Air Conditioning
  By S. Venkatraman
  The challenge thrown by IBM to Ralph Liebert in the early 60s resulted in the modern precision air conditioner.
• Precision Air Conditioning
  By Suresh Balakrishnan
  Understanding the importance of Server rooms and selecting the right capacity and type of precision air conditioner is the ke6y to a reliable facility.
• Air Conditioning of Large Call Centres
  By Satish Iyengar
  Understanding the functioning of a Call centre and its special needs will help in designing the critical air conditioning requirements.
• HVAC - its Relevance to Telecommunication
  By V.M. Kohli
  The growth of telecommunication in India and the advent of Electronic exchanges has changed the type of air conditioning equipment specified and used by BSNL today.
  

• Cold Air Distribution Systems
  By R. V. Simha
  A detailed study of such systems brings out the several benefits that can accrue from their use in commercial and office buildings. Reduced air flow rates translate into smaller ducts and AHUs, increased ceiling heights and lower energy costs. High-rise coils result in smaller piping and pumps. Overall savings in initial and operating costs are a result.
• Designing and Installing Large Cold Stores using Prefab Insulated Panels.
  By Hiru M. Jhangiani
  With the increasing emphasis on horticulture, processed foods and logistics of distribution thee is a growing demand for larger cold stores with shorter completion periods. This can be met by use of prefab insulated panels and factory built condensing units. Several issues that are relevant to modern designs of such cold stores are explained.
• A Systematic Approach for reviewing the Selections of Ch. W. Fan Coil Units
  By Atul Mathur
  The important issues that must be nailed down before approving the selection and performance of fan coil units are clearly brought out, so that capacity problems in the future are avoided.
• Outlook for Under Floor Air Distribution
  By Fred Bauman and Tom Webster
  Some designers are predicting that 35% of new office buildings in the USA will have raised floors and some form of under floor air distribution by 2004. There systems offer several advantages over conventional overhead distribution systems and these are explained, along with possible drawbacks to more rapid growth.
  

• Hospital HVAC Design : A Challenge for IAQ, Energy Recovery and System Reliability
  By George Sze, Lek Siang Hwa, Atul Mathur
  Written from the perspective of consultants and based on the authors' experience from a number of hospital projects completed in Singapore, the article provides an overview of hospital HVAC design.
• How Not to Design, Install & Maintain AC Systems for OTs
  By Rumi H. Bharucha and Dewang Dalal
  A surgeon's skill in an OT can often be forgotten if the IAQ in the OT is poor. The article tells you why.
• Energy Efficient HVAC Systems for Health Care Facilities
  By Pradeep Nadkarny & Satish Rao
  Minimizing energy costs during the design stage of an HVAC system can help hospitals become more affordable.
• HVAC Design Criteria for Isolation Rooms
  By Pranab Chowdhury & Samta Bajaj
  With the resurgence of communicable diseases such as TB, AIDS and the need to protect bone marrow or organ transplant patients, the need for isolation rooms is growing.
• Planning for HVAC Systems in Hospitals in India
  By Dr. Vivek Desai
  An expert in hospital planning writes about the condition of hospitals in India and the need to educate entrepreneur doctors planning to construct new hospitals.
• New Ventilation Guidelines for Health Care Facilities
  By Paul Ninomura & Judene Bartley
  The 2001 edition is the latest revision in the "Guidelines for Design and Construction of Hospital and Health Care Facilities" in USA. Changes pertaining to HVAC are summarized in the article.
• Filtration of Airborne Microorganisms
  By W.J. Kowalski & W.P. Bahnfleth
  The authors explain the selection and evaluation of air filters for hospital application.
  

• Selecting Cooling Coils without Proprietary Software
  By Amrit B. Marathe
  Using a computer and a software program to select cooling coils is simple. But if you don't have access to such software you can still make a reliable selection with the help of this article.
• CO₂ / NH₃ Cascade Refrigeration Systems
  By S. Raha
  Why such systems are clearly superior to conventional two-stage ammonia systems for low temperature (around - 40ºC) applications in food processing and similar industries are clearly explained by the author.
• Investigation of Condensation Problem on Chilled Water Piping
  By Richard Stone and Atul Mathur
  Chilled water pipes are insulated for energy efficiency, avoiding heat gain to the chilled water and preventing surface condensation. In humid climates, condensation problems can occur if the specs are not right and insulation is not installed properly. This article reviews a case where such problems did occur.
• Achieving High Chilled-water Delta Ts
  By Donald Fiorino
  The article recommends practical methods for achieving 8.3ºC (15ºF) or greater chilled-water differentials in variable flow hydronic cooling systems. Selection of adequate size cooling coils plays an important part in achieving high Delta Ts.
• Condensate Traps for Cooling Coils
  By Ronald Brusha
  There are widespread misconceptions about how condensate traps work and how to properly size them. Simple, inexpensive details can make them much easier to inspect and maintain.
  
  

• Air Conditioning of Auditoriums
  By M. H. Lulla
  Armed with practical experience of designing air conditioning systems for 40-odd auditoriums, this well-known consultant from Chennai guides young engineers on the basics of design for this application and gives examples of a few auditoriums where he has used, either ducted-split ACs or central plants.
• HVAC Systems for Theatres, Auditoriums & Cinema Halls
  By Sudhir K. Sinha and R. K. Dastur
  Noise and noise control in HVAC systems are explained in great detail & the various figures & tables provided, are an excellent source of reference for the experienced engineer, who can then avoid many pitfalls, when it comes to preparing drawing layouts & installing equipment.
• Air Conditioning of Multiplexes
  By Pankaj Dharkar
  Multiplexes are the latest craze in the country and this author has designed a large number of them. Peculiarities of these complexes & how to design an efficient HVAC system to meet such needs are explained. How to go about collecting return air, under the seats, is well-illustrated.
• Introducing: New Perishable Cargo Centre at Mumbai International Airport
  By Mahesh Aswaney & A. S. Garde
  A modern refrigerated cargo centre capable of handling storage of flowers, fresh fruits & vegetables, while they are in transit at Mumbai airport en route to the Middle East & Europe, has just been completed.
• Project Management : The Pitfalls
  By Atul Mathur
  A large population of air conditioning professionals is involved in project management. While all project teams set out to finish the project in time, within the budgeted cost & required quality stanndards, not every team succeeds. All the pitfalls are very clearly brought out by the author.
  

• Remote Nodes for Telecommunication, Selecting the ideal air conditioning sysytem
  By S. K. Sengupta
  One would think that air conditioning a 9m² room would be very simple. Install a room AC & be done with it. But when that room houses electronic equipment for mobile phones, it is no longer a simple job & the author tells you why.
  
• Cooling Coils
  Factors that influence design & selection
  By Ramesh Paranjpey
  In simple language, the author explains the several factors that good design & careful selection of a common cooling coil. With a variety of tube sizes, fin spacings & materials available today, the application engineer needs to be well informed.
• Refrigeration for Carbonated Beverages
  By Sandeep V. Bapat
  What makes one soft drink frizzier or more bubbly than another? Better carbonation & better refrigeration! The author explains how soft drinks are manufactured, how refrigeration capacity is calculated & types of systems used.
• Dehumidification Performance of HVAC Systems
  By John Murphy
  The importance of maintaining relative humidity below 60% in comfort applications & different ways of achieving this are clearly explained.
• Avoid Legionellosis Lawsuits over Cooling Towers
  By W. Craig Meyer
  Controlling Legionella in cooling towers can prevent the disease Legionellosis, which is common in the USA & the developed world. How to take care of your cooling tower is explained.
  

• The Facts about Fire & Smoke Dampers
  By Anil Maheshwari
  Correct applications & stringent testing standards are essential, if fire & smoke dampers are to perform their function during a fire. This article gives all the facts on these issues.
• The Market for Duct Systems: What's New
  By Ronald J. Wilkinson
  Concerns for improving IAQ are bringing about changes in old fashioned ductwork.
• Ductwork Leakage & Leak Testing (Part 1 of 2)
  By R. V. Simha
  If you dont know how much your ductwork leaks there is very little incentive to improve fabrication practices. International leakage norms are explained in Part I.
• Pills for sick Duct Systems
  By Melvin A. Ramsey
  A few fundamentals of good duct design & practical tips on air distribution are explained in this simple article.
• Wet Ceilings
  By M. H. Lulla
  Almost unbelievable but true, this rael-life experience drives home the importance of proper design of air distribution systems.
• VAV Systems
  By William J. Coad
  Starting with the evolution of VAV boxes, the author explains his recommendations for treating ventilation air by means of a seperate AHU.
• Achievig Ducting Excellence
  By Pratap Gidwani
  Based on his practical field experience, the author suggests some recommendations for raising the general standard of ductwork in India.

• Air-Cooled Chillers: Myths & Facts
  By Nirmal C. Gupta
  Air is abundant, clkean water is becoming scarce. Air-coll chillers were born out of need for massive air conditioning needs in the Middle East. They are simple to operate & their power consumption is not as high as you imagine.
• Ductwork Leakage & Leak Testing (Part2 of 2)
  By R. V. Simha
  If you dont know how much your ductwork leaks, there is very little incentive to improve fabrication practices. Part 2 explains the nitty-gritty of leakage measurement & calculations.
• Historical Developments in Air Cleaning & Clean Rooms
  By B. Bhattacharjee
  Where we were & where we are today, the developments along the way that have helped us to get there are clearly explained. The future calls for more work in the formulation of local codes & standards.
• Eliminating Volatile Organic Compounds
  By Hamish Shahani
  Clean room contaminants in the form of volatile organic compounds (VOCs) need to be controlled in certain applications, including hospital operating suites. The author throws some light on this obscure subject.
• Dealing with Glide Refrigerants
  By Dr. Guy Hundy
  With the phase out of CFCs, a new breed of refrigerants has emerged. The term "glide" as it applies to refrigerants is explained along with standard rating conditions for compressors using such refrigerants.