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Explanation:

Smothering

• It means cutting off the supply of Oxygen, access of fresh air into the fire, using sand, foam, etc., to cover fire. 

Starvation

• Starvation is achieved by the removal of the fuel burning in the fire. Any combustible material can be removed or gas or fuel flows shut off.

Cooling

• The most commonly used fire fighting medium is water. Water, referring to the triangle of fire, cools the heat being produced in the fire to below ignition temperature.

Concept:

Absolute zero temperature:

• The lowest temperature at which there is no heat energy remained in the body is called an absolute zero temperature of that body.
• Degree Celsius and Kelvin are the standard units of the temperature.

The relation between Degree Celsius (C) and kelvin (K) is given by:

K = C + 273.15°C

EXPLANATION:

Absolute temperature, K = 0 kelvin

K = C + 273.15°C

C = 0 – 273.15 = - 273.15°C

C =  - 273.15°C

Explanation:

Asbestos Cement Product:

1. Asbestos cement products are the most common asbestos-containing materials in use and their manufacture consumes 70% of world asbestos production.
2. The range of products includes wall and roof sheets (corrugated and flat), roof tiles, rainwater goods, sewerage pipes, and pressure pipes.
3. Asbestos cement products are manufactured using mechanized processes with 10–20% asbestos fibre being mixed with Portland cement slurry. After forming into the desired shape they are usually steam cured with low-pressure steam at 80°C or high-pressure steam at 170°C. Up to 40% of the cement may be replaced by silica flour if high-pressure steam is to be used for curing. Curing is sometimes achieved at ambient temperature or by autoclaving.
4. In the thin section, asbestos cement typically consists of finely divided asbestos fibre dispersed in a matrix (act as reinforcing material) of Portland cement, including abundant partially hydrated relict cement grains.
5. Asbestos cement is usually manufactured using chrysotile (white asbestos), although crocidolite (blue asbestos) and amosite (brown asbestos) are used for some products. The asbestos fibres and fibre bundles usually exhibit a preferred orientation subparallel to the length of the sheet, tile, or pipe that they are incorporated within.
6. Since the early 1900s, cement has been reinforced with naturally occurring asbestos fibres to make asbestos cement (AC). This is much used for things like water pipes, corrugated roofing sheets, and building boards. Chrysolite is generally used as a reinforcing material in asbestos-cement building products.

• Manufacture and new-build use of AC has been banned in many countries (owing to the risk of workers contracting lung cancer by breathing in asbestos dust), but AC continues to be made and used elsewhere.

Explanation:

Vapor Cloud Explosion (VCE)

• A vapor cloud explosion (VCE) results from the ignition of a flammable mixture of vapor, gas, aerosol, or mist, in which flame speeds accelerate to sufficiently high velocities to produce significant overpressure.
• VCEs are generally associated with the release of a sufficient quantity of flammable gas or vaporizing (flashing) liquid from a:

1. storage tank
2. process or transport vessel
3. piping system

Explanation:

Proper Use Of Fire Extinguishers (P.A.S.S.)

To use fire extinguishers correctly, remember the P.A.S.S. acronym:

• P = PULL the pin on the fire extinguisher
• A = AIM the extinguisher nozzle at the base of the fire
• S = SQUEEZE or press the handle
• S = SWEEP from side to side until the fire appears to be out

The R.A.C.E. Acronym And Fire Extinguisher Use

If you are involved in a fire, remember R.A.C.E. to help you respond safely and correctly

• R = RESCUE anyone in immediate danger from the fire, if it does not endanger your life
• A = ALARM: sound the alarm by calling “2600” (oncampus locations only) and activating a pull station alarm box
• C = CONFINE the fire by closing all doors and windows
• E = EXTINGUISH the fire with a fire extinguisher, or EVACUATE the area if the fire is too large for a fire extinguisher.

Explanation:

Proper Use Of Fire Extinguishers (P.A.S.S.)

To use fire extinguishers correctly, remember the P.A.S.S. acronym:

• P = PULL the pin on the fire extinguisher
• A = AIM the extinguisher nozzle at the base of the fire
• S = SQUEEZE or press the handle
• S = SWEEP from side to side until the fire appears to be out

The R.A.C.E. Acronym And Fire Extinguisher Use

If you are involved in a fire, remember R.A.C.E. to help you respond safely and correctly

• R = RESCUE anyone in immediate danger from the fire, if it does not endanger your life
• A = ALARM: sound the alarm by calling “2600” (oncampus locations only) and activating a pull station alarm box
• C = CONFINE the fire by closing all doors and windows
• E = EXTINGUISH the fire with a fire extinguisher, or EVACUATE the area if the fire is too large for a fire extinguisher.

Explanation:

Hydrophilicity

• Hydrophilicity is a critical feature in fluid flow mechanisms used for microfluidic devices.
• The resistance to fluid flow is especially important in a passive flow device where capillary action is used to move fluid such as test strips.
• Hydrophilic surfaces are “water-loving”, in that they allow fluids to wet out or flow across a surface and promote fluid flow through a channel into a test chamber.
• The surface energy or degree of hydrophilicity varies widely in device construction materials from water-repelling or hydrophobic (low surface energy) to hydrophilic (high surface energy) where water easily wets a surface.

Explanation:

Trenches​

• A trench is a long narrow excavation which is deeper than it is wide, and open to the surface along its length.
• Trenches are generally excavated to install or maintain underground services or to investigate what is beneath the surface.

Confined space

• A confined space is an enclosed or partially enclosed space, not intended or designed primarily for human occupancy.
• Trenches beyond the depth of 1.2 meter is considered as a confined space.

Explanation:

Cryogenic liquids

• Cryogenic liquids are liquefied gases that are kept in their liquid state at very low temperatures.
• The word "cryogenic" means "producing, or related to, low temperatures," and all cryogenic liquids are extremely cold.
• Cryogenic liquids have boiling points below -150°C (- 238°F)
• All cryogenic liquids are gases at normal temperatures and pressures.
• These gases must be cooled below room temperature before an increase in pressure can liquefy them.
• Different cryogens become liquids under different conditions of temperature and pressure, but all have two properties in common: they are extremely cold, and small amounts of liquid can expand into very large volumes of gas.

Each cryogenic liquid has its own specific properties but most cryogenic liquids can be placed into one of three groups:

• Inert Gases: Inert gases do not react chemically to any great extent. They do not burn or support combustion. Examples of this group are nitrogen, helium, neon, argon and krypton.
• Flammable Gases: Some cryogenic liquids produce a gas that can burn in air. The most common examples are hydrogen, methane and liquefied natural gas.
• Oxygen: Many materials considered as non-combustible can burn in the presence of liquid oxygen. Organic materials can react explosively with liquid oxygen. The hazards and handling precautions of liquid oxygen must therefore be considered separately from other cryogenic liquids.

Explanation:

• The glass used for lighting fixtures shall be clear and suitable for use under conditions involving exceptional risk of mechanical damage.
• All good glass fixtures shall be provided with either galvanized steel or epoxy powder coated mild steel protective wire cage.
• There are three types of glasses are there in flameproof lighting as per Indian Standard

Explanation:

• A reasonable temperature for a workplace depends on work activity and the environmental conditions of the workplace.
• During working hours, the temperature in all workplaces inside buildings shall be reasonable.
• It is usually accepted that people work best at a temperature between 16°C and 30°C, although this can vary depending on the kind of work being done. 

The following temperatures for different working areas:

1. Heavy work in factories: 13°C
2. Light work in factories: 16°C
3. Hospital wards and shops: 18°C
4. Offices and dining rooms: 20°C 

Explanation:

• Considered to be the world's worst industrial disaster, the Bhopal gas tragedy took place on 2-3 December 1984 at the Union Carbide India Limited plant in Bhopal, Madhya Pradesh.
• It was a gas leak incident in which a highly toxic gas called methyl isocyanate leaked from the pesticide plant and spread to the small towns near the plant. The death toll is estimated to be somewhere between 3,787 to 16000.
• Lower levels of exposure to the gas cause skin and eye irritation, chest pain, asthma, and dyspnea. Higher levels of exposure cause pulmonary edema, hemorrhages, bronchial pneumonia, and death.

Explanation:

Classification Of Building Based On Occupancy

General Classification

All buildings should be classified, according to the use or the character of occupancy in one of the following groups :

1. Group A Residential
2. Group B Educational
3. Group C Institutional
4. Group D Assembly
5. Group E Business
6. Group F Mercantile
7. Group G Industrial
8. Group H Storage
9. Group J Hazardous

Group G industrial buildings

• These should include any building or part of a building or structure, in which products or materials of all kinds and properties are fabricated, assembled, manufactured or processed, for example, assembly plants, laboratories, dry cleaning plants, power plants, pumping stations, smoke houses, laundries, gas plants, refineries, dairies and mills.
• The hazard of occupancy, for the purpose of the Code should be the relative danger of the start and spread of fire, the danger of smoke or gases generated, the danger of explosion or other occurrence potentially endangering the lives and safety of the occupants of the buildings.
• Hazard of occupancy should be determined by the authority on the basis of the character of the contents and the processes or operations conducted in the building, provided, however, that the combustibility of the building, the flame spread rating of the interior finish or other features of the building or structure are such as to involve a greater than the occupancy hazard, the greater degree of hazard should govern the classification.
• Where different degrees of hazard of occupancy exist in different parts of a building, the most hazardous of those should govern the classification for the purpose of this code, except in as far as hazardous areas are segregated or protected as specified in the code.

Buildings under Group G shall be further sub-divided as follows:

1. Subdivision G-1 - This subdivision should include any building in which the contents are of such low combustibility and the industrial processes or operations conducted therein are of such a nature that there are no possibilities for any self-propagating fire to occur and the only consequent danger to life and property may arise from panic, fumes or smoke, or fire from some external source.
2. Subdivision G-2 - This subdivision should include any building in which the contents or industrial processes of operations conducted therein are liable to give rise to a fire which will burn with extreme rapidity and give off a considerable volume of smoke, but from which neither toxic fumes nor explosions are to be feared in the event of a fire.
3. Subdivision G-3 - This subdivision should include any building in which the contents or industrial processes or operations conducted therein are liable to give rise to a fire which will burn with extreme rapidity or from which poisonous fumes are explosions are to be feared in the event of a fire.

Explanation:

Different ways of venting fire gases

• Fire ventilation can be performed in three different ways:
  1. horizontally
  2. vertically
  3. mechanically (with the help of fans).
• Whichever way is most suitable depends, among other things, on how inlets (openings where fresh air flows in), outlets or exhaust openings (openings where fire gases flow out) and the fire are located in relation to each other in terms of distance and height.
• The most appropriate way also depends on what other aids are used and other measures that are initiated.
• Be aware that the different ways of venting have consequences of different kinds.

Explanation:

• Fire suppression systems can connect to a fire alarm panel so that activation of the system causes the panel to signal an alarm.
• Wet pipe automatic sprinkler systems commonly have water flow detectors.
• As the water starts to flow in the sprinkler piping, it causes a vane to swing into an alarm position; this sends an alarm to the fire alarm panel.
• Dry pipe sprinkler systems may have pressure sensors for the same reason. 
• The initial attack is the first phase of fire suppression.