91) What is heat stroke? What are the different stage through which a person undergoes before he gets heat stroke?
During hot days, due to dehydration, body temperature increases beyond safe limit, because of break down of body’s heat regulating mechanism. Due to this the person collapses and if not taken care off he can even die. This is called heat stroke.
Generally pulse raises 20 beats per minute for each 1 degree C rise in temperature, heat cramps: Exercising in hot weather can lead to muscle cramps, because of brief imbalances in body salt.
Heat exhaustion: further losing of fluid and salt can lead to dizziness and weakness body temperature may rise up to 102 degree F.
Heat stroke: In some cases, extreme heat can upset body’s thermostat, causing body temperature to rise to 105 degree F. or higher. Symptoms are lethargy, confusion and unconsciousness, heat stroke can kill.
92) How is the soil classified? What is the slope to be given for each type of soil while excavating?
The following is a short explanation of soil classifications. You should check the standard for detailed information regarding classifying soils
.Type A soils
Cohesive soils that have an unconfined compressive strength of 1.5 tsf or greater.
E.g., clay, salty clay, sandy clay & clay loam
Type A soils cannot have or be subjected to the following:
Subjection to vibration from traffic, pile driving or similar conditions
Been previously disturbed
Or if it has been subjected to other factors that would change it’s classification
Type B soils
Cohesive soils that have an unconfined compressive strength greater than 0.5 tsf but less than 1.5tsf
E.g., angular gravel, silt, silt loam, sandy loam and previously disrobed soils except those which would be classified as Type C soil
Also includes soils that meet some of the requirements of Type A soils but is fissured or subject to vibration; or dry rock that is not stable.
Type C soils
v Cohesive soils with an unconfined compressive strength of 0.5tsf or less
v E.g. granular soils including gravel, sand and loamy sand
v Also submerged soil or soil from which water is freely seeping or submerged rock that is not stable
v A natural solid mineral material that can be excavated with vertical sides and will remain intact while exposed.
Maximum allowable slopes
v Stable rock: vertical (90degrees)
v Type A: ¾ :1 (53degrees)
v Type B 1:1 (45degreed)
v Type C : 1 ½ : 1 (34degrees)
v ½ : 1 (63 degrees ) slope is allowed for only short term excavations that are 12feet deep or le
93) What are the precautions to be taken while handling and storing compressed cylinders?
Where cylinders are to be kept for an appreciable length of time should be provided to ensure that they cause no hazard to workers or public in the area.
Cylinders should be stored in a well ventilated area-preferable in open air but protected from the weather.
The store should be away from fire risks and source of heat and ignition. Nothing else should be stored in the area.
The cylinders should be stored upright on a firm level, well drained surface free from hollows and cavities. All long grass, weeds etc. should be removed.
Cylinders should be secured so as they are prevented from falling over, when in storage or use.
Cylinders should be segregated within the store according to type and weather full or empty.
Oxygen and oxidizing gases should be separated flammable gases by 6m or by a fire resistant partition.
No electrical apparatus should be installed within a cylinder store unless it is constructed to a suitable standard for the hazard.
No cylinder should be used in a storage area.
Appropriate warning signs “HIGHLY FLAMMABLE”. NO SMOKING”, “FULL/EMPTY” etc. should be displayed.
Suitable fire fighting apparatus should be situated adjacent to the store. Typically dry powder fire extinguishers. These should be inspected and maintained at intervals not exceeding 1 year.
Where cylinders area required to be stored in a compound this should be located not less than 3 meters from any building, site or public access road. The compound fence should be a minimum of 2 meters high, and it should have two means of escape, with the gates opening outwards.
Where it is necessary to take precautions vandalism or theft, suitable protection cages should be used.
Each cylinder should be adequate marked to include the manufacturer’s mark and serial number, together with an indication of the specification to which the cylinder is constructed and its years of manufacture. A date of test and pressure test, together with weight of cylinder and the name of the product, should be displayed.
15)When gas cylinders are to be transported they should be protected from physical damage and the consequences of any leaks that may occur minimized.
16)Move cylinders by hand in proper cylinder trolleys where the cylinder is secured in the trolley.
17)Take great care when lifting cylinders as they can be very heavy and awkward to handle.
18)Before moving any cylinders remove all attached equipment including regulators and safety cap must be provided.
19)The cylinders should be properly supported and secures within the vehicle so they cannot move during the journey. They should be totally within the vehicle and protected from impact.
20)The cylinders should be checked to ensure that the valves are closed and there are no leaks.
21)The vehicle should be equipped with a suitable fire extinguisher. Typically dry powder, minimum capacity 2kg.
22)There should be no smoking within the vehicle while crying cylinders.
23)The driver of the vehicle should be conversant with the load and have written information on the hazards and the action to be taken should any problems occur. The driver should also have training in the operation of the fire extinguisher and any other safety equipment carried.
94) What are the type of fire extinguishers commonly used and briefly, explain each one?
Multipurpose dry chemical, carbon dioxide, halon, wet chemical or foam, pressurized water are the commonly used fire extinguishers.
Multipurpose dry chemical / class “A”, “B”, or “C” fires.2.5-20lb. dry chemical (ammonium phosphate) pressurized to 10.5-18 bar by CO2 gas (8-25 seconds discharge time). Has pressure gauge to allow visual capacity check.5-20ft maximum effective range. Extinguisher by smothering burning materials
Smothering – Cut off oxygen / close the ventilation using fire extinguisher
Starving – Remove the fuel / remove the material going to burn
Cooling – Reduce the heat / use water
Carbon Dioxide – Class “B” or “C” fires 2.5-100lb. of CO2 gas at 150-200 psi (8-30seconds discharge time).
Has NO pressure gauge-capacity verified by weight 3-8 ft. maximum effective range.
Extinguisher by smothering burning materials, Effectiveness decreases as temperature of burning material increases.
Halon – Class “A”,”B”, or “C” fires (smaller sizes ineffective against class “A”). 9-17 lb. Halon 1211 (pressurized liquid) releases as vapor (8-18 seconds discharge time). Has pressure gauge to allow visual capacity check 9-16 ft. maximum effective range. Works best in confined area – ideal for electronics fire due to lack of residue. Extinguishers by smothering burning materials, Fumes toxic if inhaled, Halon is ozone depleting chemical – production halted in Jan ’94.
Wet Chemical or Foam – Class “A”, “B” fires 1.5gal of stored pressure PRX wet chemical extinguishing agent (40 sec. discharge time) 10-12 ft. maximum effective range. On Class “K” fires, don’t use until after fixed extinguishing system has activated, Extinguishes by cooling and forming foam blanket to prevent reigniting.
What is S
95) What is the formula for incident rate?
Number of Record able injuries X 200,000 Number of employees Hour Worked 200,000 is the equivalent of 100 full time employees working for 40 hours per week or 50 weeks per year (OSHA guidelines)
96) What is First Aid and CPR?
Medical aid provide to a victim of an accident scene. This first aid is administered by trained nurse. CPR (Cardio Pulmonary Resuscitation) a first aid given to a person having heart blocked or chocked due to sudden shock.
97) What is Fire?
Chain reaction of FUEL, HEAT, OXYGEN.
A) Fuel any material which can burn like Paper, Rubber, Wood, Oil, Lubricants, Gases, Metals like Phosphorous, Magnesium.
B) Heat or temperature at which the any fuel can ignite this depends on its flash point.
C) Oxygen which is helping in combustion and is present in the air.
98) How Fire can be extinguished?
Remove anyone of the above three elements of Fire. Fire will extinguished,
A) Remove the burning material, the remaining materials will be safe.
B) Cut off the Oxygen by blanketing with foam or Fire blanket or any other materials which
can not burn the oxygen will be cut off and fire extinguished.
C) Remove or lessen the heat with water or use Carbon Dioxide fire cylinder. Never use Water for Electric Fire as water is good conductor of electricity and you will get electric shock if water is used for electric fire.
99) What common type of the fire extinguisher is used for fire?
ABC or Dry Chemical Powder Fire Extinguisher used for Solid, Liquid Gases and Electric Fire.
100) What is a Work Permit?
A written document authorizing employees to carryout a work in a designated area on an equipment specifying the hazards, safety instructions and PPE required for work.
101) What is a Confined Space?
A vessel, column, tank, pit, trench which has limited entry and access and one can not stay inside for long time due to following factors.
Lack of fresh air or Oxygen, Heat, Fumes, Toxicity of storage Contents, Noise any other annoyance, causing disturbance in normal work.
102) What is (a) THLV (b) LEL © UEL?
Threshold Limit Value, Lower Explosive Limit, Upper Explosive Limit
103) What is ASPHYXIANTS?
Chemical gases which can cause suffocation by restricting the uptake of oxygen or by respiratory paralysis or by diluting / displacing oxygen below the levels needed by human body.
104) What is a SCBA?
Self Contained Breathing Apparatus, use in confined spaces or where oxygen deficiency exists or where concentration of toxics gases is harmful to humans.
105) What is toxic Material?
A material or substance which adversely effects body or organs.
106) What are Flammable and Combustible Liquids?
Liquids that give off enough vapors to form an ignitable mixture with air and produce a flame when a source of ignition is present.
107) What is MSDS?
Material Safety Data Sheet
108) What is a Risk Assessment/Hazard Identification Plan?
Identifying hazards and risk involve in a specific job and control measures required to eliminate them or bring them to minimum acceptable limit for the job to be done in safe manner
Before erecting scaffolds assess the work area for existing and for potential future hazards which may impact on the work.
109) What are basic components of scaffolds?
a) Base Plate
b) Sill Boards
c) Screw Jack
e) Vertical tubes or Bearer also called LEDGERS
f) Horizontal tubes or Ledgers also called STANDARDS
g) Transoms connected across the width
h) Hand rails mid rails
i) Toe Boards
l) Diagonal Bracings for stability
110) What are different types of slings used for lifting?
a) Wire rope slings
b) Synthetic/Nylon Webbings
c) Chain Slings
111) When a sling is considered unsafe for use?
- 10 wire broken in one rope lay randomly distributed
- 05 wires broken in one strand in one lay
- 1/3rd of original diameter is scrapping or worn
- Kink crushing, bird caging, or other damage or distortion of wire rope structure
- Evidence of heat damage
- End attachments that are cracked worn or damaged
- Hooks open more than 15% of normal throat
- Twisted more than 10 degrees from the plane
112) What safety measure are required for SAFE CRANE OPERATION
- Crane is to be positioned on level ground
- Outriggers fully extended
- Mats to be used for stability
- Crane radius of swing should be barricaded and no one to cross under the suspended load
- Ensure clear of obstructions
- Load chart available in the cabin
- Qualified Operator and rigger to rig the loads
- Only one rigger is authorized to signal the operator
- Do not lift the load beyond the rated capacity of the crane
- Wind speed not more than 20miles/hr or 32km/hr
- Anti two block system working
- Load monitoring indicator operational
- Telescopic boom free moment
- Operators cabin have clear view and not obstructed
PORTABLE ELECTRICAL TOOLS
114) Why this should be used with electric tools?
To protect the workers from shock in case of current leakage
115) What is the sign of a potable electric tool having double insulated?
116) Why tools having broken insulation must not be used?
To avoid possible electric shock
117) What is meager test?
The insulation break down test is known as meager test
118) Why meager test is necessary for electric tools?
A tool having subjected to harsh use at site needs to be tested for insulation break down to avoid possible electric shock.
119) Why dead man switch should be used on electric tools?
To cut off the power supply to the tool in emergency
120) Why Safety Training is required?
To make the employees familiar with the hazards associated with their work safety orientation and some other trainings is required, also special craft training is required before start of work, safety assessment risk assessment for potential hazards is essential which covers the general hazards and specific hazards associated to the work being undertaken and the control measures applied to eliminate or minimize the potential of harm to the employees, therefore emphasis of accidental loss of resources (Men and Materials) to reduce the direct and indirect costs and loss time delays due to interruptions providing safe and friendly environment for timely completion of projects therefore imparting plays an important role in loss control and it is an idea sound business to have safety culture prevailing on the construction sites.
121) What is LOTO?
Lock out tag out, to lock out specific breakers are used for the maintenance of all equipments
122) What is GFCI?
Ground Fault Circuit Interrupter
123) What is Excavation and Ditches?
Digging of land with Machine or with men
124) What is Confined Space?
Space heaving a limited entrance or egress but that is large enough to bodily entrance and performed the work, i.e.
A) High Temperature
B) High Noise
C) Fall from Elevation
E) Oxygen deficiency
125) What are the scaffoldings and its kinds and it’s Consists?
It is temporary platform
A) System Scaffolding
B) Under Hang Scaffoldings
C) Mobile Scaffolding
D) Bract Scaffolding
E) Tower Scaffolding
F) Tube and Copular scaffolding
A) Sole Boards
B) Base Plates
- Right angle couplers
- Right angle Double couplers
- End to End Couplers
- Adjustable Couplers
- Girder Couplers
F) Top rail
G) Mid rail
- Should be in between top rail and toe boards
H) Toe Board
- Distance between toe board to top rail should be 38 to 43 inches
- Zigzag bracings
- Transverse bracings
- Longitudinal bracings and cross bracings
126) What is KENAPI?
To Safe Workers from falling objects we can use KENAPI nets and catch plate forms.
127) Which Permit is use for Vehicles?
Hot Work Permit
128) What is Risk Assessment?
Simply we can defined it with
v What can go wrong
v What can cause its going wrong
v What can we do to prevent it from going wrong
129) What is Evocation?
v Stop the work and switch off equipment and proceed to nearest assembly ground
v Always walk against wind direction
v If you driving a vehicle, stop on road side switch off engine and proceed to assembly area and let the key should inside the ignition point.
v Head count will taken by Safety Officer in assembly area.
v Do not come to work tell all clear alarm sounds.
130) How many types of accident in construction area?
Last work day case
Restricted work case
Medical treatment case
First aid case
Near miss Incident
v An incident, which could cause property damage or personal injury and if we will not stop near miss incidents then can happen an accident.
131) What is Toolbox Talks?
Awareness about work situation to the employee is called toolbox talk
A development of safety bricfings and deal with special issues at the workplace.
132) What is DBA?
The frequency of noise at which we should use ear plug or muffs is 85DBA.
v DBA Decibel at scale A
133) What are LEL and UEL?
v Lower Explosive Limit
v Upper Explosive Limit
Level of Flammable gases or toxic gasses should be zero
Level of Oxygen should be in between 19.5 – 23.5 in volume
134) How many scaffolding tags used in scaffolding?
v Green tag - Scaffolding is safe to work
v Yellow - Use full body harness is required with double Lyn yard
v Red tag - Means scaffolding is unsafe or not able to use (only scaffolder can work)
Note: Safety Harness can bear the weight 2450kg
135) What are the precautions for Welding?
v Hot work permit is required
v Area should be barricaded and warning signage should be placed
v Area should be clean at least 8 meters (free from combustible materials)
v Fire extinguisher and fire blankets should be available
v Trained fire watch man should be available
v Fire water drum should be available
Note: Welder must use complete PPE’s (Welding Helmet, Gloves and Long sleeves shirt)
Safety is a state where risk has been eliminated or reduced to an acceptable level
Fire is a chemical reaction involving rapid oxidation or burning of a fuel. It needs three elements to occur
Fuel can be any combustible material – solid, liquid, or gas. Most solids and liquids become a
Oxygen the air we breathe is about 21 percent oxygen. Fire only needs an atmosphere with at least 16 percent oxygen.
Heat is the energy necessary to increase the temperature of the fuel to a point where sufficient vapors are given off for ignition to occur.
Flash Point is the lowest temperature at which a fuel produces enough vapors to ignite in the presence of a heat source.
Dust consists of solid particles and is created by such operations as grinding or sieving of solid materials, controlled detonations and various drying processes.
Fumes are finely particulate solids which are created by condensation from a vapor, very often after a metal has been converted to the molten state. Fumes are usually highly toxic.
Gas is the formless chemical which occupies the area in which it is enclosed. There are many toxic gases used in industry, such as chlorine.
Mist consists of finely suspended droplets formed by condensation from a gas or the atomizing of a liquid or from aerosols.
Vapors are the gaseous form of a solid or a liquid, rise in temperature causes the vaporization. Examples are organic solvent vapors’.
Liquid is a typical example of a liquid, Can be in other forms as droplets or aerosols.
149) Very Toxic
Substances and preparations which in very low quantities cause death or acute or chronic damage to health when inhaled swallowed or absorbed via the skin.
Toxic substances and preparation that in low quantities cause death or acute or chronic damage to health when inhaled swallowed or absorbed via the skin.
Corrosive is substances and preparations that may on contact destroy living tissues.
The density of a material is defined as the mass of one cubic meter of material
DENSITY = MASS/VOLUME
153) Specific Gravity
We can therefore say that any liquid that will not dissolve (not miscible) in water, with a specific gravity higher than 1, will sink, whilst those with a specific gravity lower than 1 will float on top. For example:
1m3 of water (1000 liters) weights 1000kg
1m3 of aviation gasoline (1000 liters) weight 720 kgs
Heat is a form of energy. Heat can be produced by chemical means, e.g., by burning aviation fuel or by mechanical means, by fiction. Passing electric current through a resistor also produces heat as in an electric fire.
Substances that consist of only one type of atom are known as elements. EX. CARBON
If an element consists of more than one of the same type of atom, chemically bound together, it is known as a molecule. EX. OXYGEN, The term molecule can also be used to describe a substance that is made up of more than one type of atom, water is example.
A mixture is a term used to describe a substance that is made up of more than one type of molecule. EX. WATER
Combustion is a chemical process. For it to occur, oxygen, usually from the air, must combine with a fuel. A fuel is any substance that will burn and may be in any one of the three states, solid, liquid or gas. EX. SMOLDING OR FLAMING
(% Fuel/Air by volume)
159) Organization Culture
Shop floor representatives, supervisors and managers who meet to discuss general health and safety matters affecting the company
A person’s point of view, or their way of looking at something.
161) Mistakes or Errors
Doing the wrong thing, believing it to be right
162)Influence of peer group
A peer group is a group of individuals of a similar age or background with whom a person mixes in a social context.
163)Work place group
The workplace group is such a group and we behave in accordance with the collective, accepted behavior of the group.
Communication is defined as, imparting, conveying or exchanging information, ideas or opinion by the use of speech, written, or graphics.
Written a postal service or a notice board
166) Oral or Verbal (SPOKEN) Communication
Oral or Verbal (spoken) a personal interview or telephone system
167) Notices, Posters, Films
Used to draw attention to hazards and risks or safe practices and measures, need to be ‘eye catching’ and relevant.
168) Tool Box Talks
A development of safety briefings and deal with specific issues at the workplace
169) Employee Hand Book:
Key document laying out company policy and certain procedures, Effective as part of induction training
The purpose of an investigation is primarily to find the cause, with the intention of preventing a recurrence, rather than to blame
171) Reactive Monitoring
Reactive Monitoring, which is used in the investigation of accidents, incidents or dangerous occurrences-After
172) Proactive Monitoring
Pro-active monitoring, which involves checking that standards, practices, procedures and system are being complied with. Before
173) Maintenance Inspections
Inspections involve examining, testing and making repairs/adjustments to such items, often specified by the manufacturer or supplier.
174) Safety Inspection
A formal inspection by a team of inspectors who go round an area or section of work to check on standards; e.g floor condition, HK, warning signs, fire equipment
175) Safety Survey
An in-depth examination of specific procedures such as the introduction of new equipment, or investigating a rise in accident or incident rate
176) Chemical Hazard
Liquids, dusts, fumes, mists
177) Biological Hazards
Exposure to bacteria, viruses and fungi
178) Physical Hazard
Mechanical, noise, radiation, heat etc. also includes ergonomic factors
179) Psychological Hazards
Refers to mental stress
180) Safe Work System
A safe system of work is: a formal procedure which results from systematic examination of a task in order to identify all the hazards
181) Permit to Work
A permit to work can be described as: A formal document giving written.