Interview Questions.

Question 1. What Is A Gas Analyzer?

Answer :

Gas Analyzer is an device used to degree the awareness of a recognised gas in given combination of gases from a process / flow.

Question 2. Why Are Gas Analyzer Used?

Answer :

Gas Analyzer is used to Monitor Process, Enhance Safety, Increase Efficiency, Monitor Emission and Improve Quality.

Instrumentational Engineering Interview Questions
Question 3. Where Are Gas Analyzer Used?

Answer :

They are used in packages in all fundamental industries which include Refineries & Petrochemicals, Chemical Plants, Critical technique, Inerting Applications, prescribed drugs, Fertilizers, Glass, semiconductors, Boilers, Heaters, Thermal crackers, Incinerators, non-stop monitoring of Stack, Industrial gas manufacturers and its customers

Question four. What Is The Difference Between Gas Detectors And Analyzers?

Answer :

Detectors come across conditions out of doors ordinary operating parameters and are installation to alarm.
Analyzers determine in actual time, the quantity/concentration a stated gasoline is in the circulation / Process.

Question five. What Is The Different Measurement Techniques Used In Gas Analyzers?

Answer :

There are many exclusive sensors used to research gases. Types of popular sensors consist of Electrochemical, Paramagnetic, Thermal conductivity, Infrared, PID, FID and many others.

Safety Officer Interview Questions
Question 6. Why Are Different Kinds Of Sensors Used?

Answer :

The sensors are designed to stumble on / degree the particular bodily or chemical properties of gases. Hence to differentiate between extraordinary gases in a aggregate of gases (a process or a flow) distinct sensor techniques are used.

Further Sensor desire also relies upon upon required accuracy, specs, lifestyles expectancy and fee.

Question 7. Does Gas Analyzer Equipment Need Maintenance And Calibration?

Answer :

Yes. However in a nicely Designed and commissioned gadget Maintenance requirement is minimal and may simplest encompass a visual inspection and verification of operative parameters and periodic replacements of consumables.

Calibration frequency depends on sensor kind, criticality of software and accuracy requirement of the manner

Oil and Gas Interview Questions
Question eight. What Is Calibration?

Answer :

Calibration verifies that the Analyzer is working well and adjusts for any sensor drift or lack of sensitivity. The method involves passing two recognized licensed concentration of the target fuel – one for Low/Zero Point and different for High/Span Point – usually from a calibration fuel cylinder and permitting the Analyzer to adjust for waft within the analyzing.

Question nine. What Is Cross-sensitivity?

Answer :

Cross-sensitivity refers to the reaction of a sensor to a gas aside from the goal fuel (additionally called an interference gasoline).

Natural Gas Interview Questions
Question 10. What Is Nox?

Answer :

A organization of compounds usually shaped with Nitrogen and Oxygen as a byproduct of combustion are referred to as NOX – Nitric Oxide (NO), Nitrogen Dioxide (NO2), Nitrous Oxide (N2O), N2O3, N2O4, N2O5, N3O4 and NO3.

Question eleven. What Does Ppm Mean?

Answer :

Parts Per Million – 1 % volume = 10,000 ppm.

Gas Detection System Interview Questions
Question 12. What Is %lel And %uel?

Answer :

The primary danger associated with flamable gases and vapors is the possibility of explosions. Explosion, like fireplace, requires three factors: gas, Oxygen, and an ignition supply. Each flamable gas or vapor will ignite best inside a specific variety of gas/Oxygen combos. Too little or an excessive amount of fuel will not ignite. These conditions are described because the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL). Any amount of gas among the 2 limits is explosive. It is important to word that every gas has its own LEL and UEL, as shown in the chart underneath. The fuel concentrations are shown by way of percentage of overall volume, with the balance as regular air.

Between those  limits explosions can arise beneath some situations, with the most explosive energy to be had at about the midpoint. Note that those limits are every so often referred to as LFL (Lower Flammable Limit) and UFL (Upper Flammable Limit). These limits are empirically decided, and numerous government now and again quote barely one of a kind figures, based on barely special experimental strategies.

Instrumentational Engineering Interview Questions
Question thirteen. What Are The Physical Fundamentals Of Ir Gas Analysis?

Answer :

The molecular vibrations of many chemical substances may be excited through energies that lie within the infrared wavelength range. Therefore, these materials soak up infrared radiation. The absorption spectrum relies upon especially on the structure of the molecule and as a consequence the levels of freedom for the motion of the molecular components, their mass, their compositions, their spacing and their binding forces. Therefore, every substance has a function absorption spectrum. For instance, in carbon dioxide molecules can be excited bending and stretching vibrations. Additionally rotational movements around one-of-a-kind molecular axes are possible, which superpose the vibrational spectrum and generate their satisfactory systems.

Question 14. How Does A Gas Analyzer With An Infrared Spectrometer (ir Spectrometer) Work?

Answer :

An IR spectrometer measures the absorption spectrums of gases. The evaluation with the spectrums which can be stored in a database permits a qualitative and quantitative reference for the substance.

Question 15. How Does Non-dispersive Infrared Gas Analysis (ndir Gas Analysis) Work?

Answer :

For this shape of gas analysis, the spectral sensitivity of a broadband thermal detector is constrained by an optical bandpass filter out. This is achieved for the variety wherein the absorption bands are observed for the gas to be decided. With the thermal detector, the transmission of the measured gasoline mixture is determined in a defined association. If the gas being looked for isn't always gift, maximum of the infrared radiation will reach the detector and the sign may be at its most. If the concentration of the gasoline will increase, absorption can even growth in line with Lambert-Beer’s regulation, and the signal will lessen hence.

Safety Instrumented System Engineer Interview Questions
Question sixteen. What Advantage Does The Non-dispersive Infrared Gas Analysis (ndir Gas Analysis) Have?

Answer :

Compared to infrared spectrometers, the NDIR gasoline evaluation is drastically less expensive. However, their use is handiest viable if the gases to be measured are regarded, and their number is low.

Question 17. Which Gases Are Not Suitable For Analysis With Non-dispersive Infrared Gas Analysis (ndir Gas Analysis)?

Answer :

Noble gases consist only of person atoms. In order to vibrate, however, as a minimum one bond is required. Noble gases can therefore no longer be detected with this method. In diatomic elemental gases together with oxygen (O2) or nitrogen (N2), only some vibrational modes may be excited via infrared radiation, in order that even right here the approach fails.

Safety Relief Valves Interview Questions
Question 18. What Are The Main Components Of An Ndir Gas Analyzer?

Answer :

An NDIR gasoline analyzer consists of an electrically or automatically modulated infrared supply, a gas cellular and usually a pyroelectric detector. An electronic device calculates the gas attention based totally on sign voltage. InfraTec gives a large number of widespread IR slender bandpass filters (NBP), which might be optimally matched to the absorption houses of the gases to be measured. The filters are mounted inside the cap of the detector, which is welded to the detector base frame. With multiple gases to be measured, the use of multi-channel detectors is usually recommended.

Safety Officer Interview Questions
Question 19. Are There Advantages Of Having An Absorption-unfastened Reference Channel For Non-dispersive Infrared Gas Analysis (ndir Gas Analysis)?

Answer :

Yes, for NDIR fuel analyzers, it's far advisable to apply a reference channel and normalize the signal of the gasoline duct through the quotient manner on this reference. The optical, mechanical and digital go with the flow of the general device is decreased extensively, and the c language between calibrations can be notably prolonged. The spectral role of the optical reference must be positioned as close as feasible to the spectral traces of the gases to be measured. A reference channel may be shared for a couple of gases, if all absorption bands lie within a spectral window from three to 5 µm or from eight to 12 µm. Without an optical reference channel, a reference can still be completed through periodically introducing a reference gas into the channel, inclusive of nitrogen.

Question 20. How Does An Infrared Flame Sensor Work?

Answer :

The pyroelectric detector of the flame sensor detects the everyday spectral radiance of burning organic substances which includes wood, herbal gasoline, oil or plastic. In order to save you a fake alarm because of daylight or other intense light assets, together with light from arc welding, two independent criteria of a flame are analyzed: First a normal flame is characterised by using a flicker frequency of 1 to five Hz. Secondly, a hydrocarbon flame carries the combustion gases carbon monoxide (CO) and carbon dioxide (CO2). Their emission bands lie inside the infrared spectral range of four.0 to four.8 µm. In order to reap a excessive signal, one uses wide bandpass filters for the detector window, which include each the radiation emission of CO and of CO2. Optionally, a further channel can be used to recognize a further combustion through product, water.

Question 21. Osha Measurers In Ppm, What Is That In Percent?

Answer :

10% is one hundred,000 PPM,
1% is 10,000 PPM,
zero.5% is five,000 PPM,
0.1% is one thousand PPM and
zero.01% is 100 PPM.