Electrical works

Major works are involve construction of substations;power supply lines installation to substations,distribution cable works ,installation of transformer stations,inters connecting cable works,installation of electrical safety gears and switches,testing of installations & electrical equipments,final installation of electrical accessories &keeping the system ready for commissioning etc. 


The expected hazards in electrical projects 

Falling of people from heights.
Electrical shock.
Injury to workers . 


The remedial measures 


Proper tools are to be used.Works above 1.8 meters are to be considers as working at height, and in this case proper scaffolding with guard rails or fall arrest systems are to be provided.For buried cables warning tapes,route markers,marking tiles to be provided inside trench before back filling.All persons at site should use PPEs.Only the ladders with insulation pads can only be used in electrical works or it is better to use fiber ladder.

safety messures (mechanical works)

Good house keeping at site at all times and removal of waste in time .
Provide fire fighting facilities in hot work areas. 
All the workers are to provide with cover all and other required ppes likes safety helmets, safety gloves , safety shoes ,safety goggles etc.
People working at height should be given safety belts and the work above 1.8 meter height to be carried out with the healp of scaffolding platforms.
AVOID WORK UNDERNEATH HEAVY PIPES ,LOADS WHEN LI8FTING IT WITH CHAIN BLOCK OR CRANE OR HIAB.
Welderts are to use aprons while welding in O/H positions.
For heavy lifting operations with crane, a rigging study is to be made and all rigging operations to be carried out under the supervission of a rigger superwiser or grade 1 rigger.
The crane should have valid certificate of worthiness and all the lifting  tools & tackels should have valid inspection certificates or stamping on the items.
Safe working loade is an important concept for lifting operations.
The skilled workers in the work area are to be trained in the use of fire figfhting equipments.
Out triggers are to be  fully extended to avoiding tipping of crane.
Flame arresters to be provided for gas cutting set.

The expected hazardfs involved in mechanical works

Injury to workers during handling of materials. 
Hands or legs caught underneath loads.Burns ,electric shock during welding works and other hot works ,short cir cute & fire incide4nts.
Collapse of cranes & other lifting equipments.
Failiear of lifting tools & tackles.
Eye injury due to falling particles during grinding,grit blasting & power brushing.
Suffocation due to excessive smoke or dust during welding & blasting operations.
Swinging of load and hitting on existing facilities during rigging operation in strong wind.
Welders trapped underneath pipes during welding works -as support are moved.
Back fire and explosion of compressed gasses during oxy -acetylene flame cutting.
Hazards due to smoking in prohibited areas.
Hazards due to bursting of pipe lines during hydro testing at high pressure range.

Civil works (safety)

The expected hazards in civil works:


Hitting of existing under ground facilities during excavation.
Falling of objects( tools, equipments,materials)on people.
Falling of people from top.Foot & hand injuries.
Eyes affected with grout or cements.Slipping & falling.
Collapse of soil during excavation.
Collapse of crane,hoist and other hang earth moving equipments,vehicles and equipments falling into excavated trench etc.

 The remedial safety measures: 


 Get proper work permit where applicable.
Locate existing under ground facilities from the latest plan drawing .
Take trial pits before excavation .
Provide proper grounding for jack hammers when in use.
Fabricate the boundary of excavation & in case of road excavation,provide flickering lamps on both sides during night together with road barriers and sign .
Provide adequate access larders,scaffolding people working at height more than 1.8 meter should be provide with safety belts.
All workers should be provide personnel protective equipments.
Sufficient shoring,De watering & disposal of excavated materials in proper places.
All the equipment and tools used for construction work should be properly maintained.
SWL of the lifting ropes to be followed strictly.

Construction of foam type extinguisher

                                 In this 95-97% of water & 3-5% of foam making compound is filled in the container. 

Top cover is made of brass or steel.
Co2 cartridge is used is of 120 gm with a pressure of 35 bar or 51 bar. 
Co2 cartridge is used to pressurize  & expel the solution which is coupled to the head .
The knob or squeezing lever fitted in the cap punters    the Co2 cartridge.
An FMB is attached to the hose for making the foam from the solution with air to make foam.


Operation of foam type extinguisher 

 Remove the safety clip / pin strike the knob/squeeze.Hold the hose to direct the foam to the seat of fire in a sweeping mode by taking support of a wall or such surface to avoid mixing up of foam with the oil.

Mechanical foam type extinguisher

In this type foam is produced from a foam solution as distinct from the  chemical form extinguisher,which is not there in use now.When the extinguisher is operated the foam solution is expelled by compressed air or by the gas  released from  a cartridge.




 THE FOAM CONCENTRATES MAY BE USED IN THE FOLLOWING TYPES : 


PROTEIN FOAM   :                                    MADE FROM ANIMAL FAT.

FLURO PROTEIN FOAM   :                         PROTEIN FOAM ADDED WITH FLUOROCARBONS. 

SYNTHETIC FOAM        :                           FOAMING AGENTS SIMILAR TO HAIR SHAMPOO OR  WASHING LIQUIDS. 

FILM FORMING FOAM  :                              AFFF & FFFP.


 ALCOHOL RESISTANT :                               P,FF OR FFFP CONCENTRATES WITH   POLYMERIZED LIQUIDS ADDED.

General safety rules for individual

Every one should behave and respect others. 
Follow and complies National rules and regulations. 
Every citizen should protect our national integrity and prevent outside evils. we have the right to safe our nation and our surroundings. 
We do our obligation to right and hand with right knowledge. Plant trees and participate in forestation and it lead to protect our environment from natural disaster.




                                            Don't kill animals and birds. In the case of family we should planed and active in following and ensure family safety. For family safety we can provide insurance for every one of the member of the family. For our home protection we must ensure to use advanced safety measures such as camera , intellectual, anti theft information devices and fire prevention system also install in your house. We should ensure safety in every discipline and every step of the journey. That is ensure safety in home , office , on children's matters , out side the home , driving etc . Today ensure our safety we can live tomorrow

Care & maintanance of extinguisher

                                              At least ones in a weak check the nozzle outlet and vent holes on the threaded portion of the cap[ for clogging.Check the plunger can be raised to the fully exerted position and that is to be cleaned if necessary.Once in a three months ,dismantle the components ,check for any damage,clean & grease them as required,stir the solution in the container with clean and dry stick.






                                               Annually operate 50 % of extinguisher and check  it project to the distance of not less than 6 meter for a minimum period of 30 seconds. Clean the extinguisher thoroughly and examine their inside for rust & corrosion .Subject rusty & corroded extinguisher to pressure test , even if they are not due for it and their performance otherwise satisfactory. Carry out the pressure test every 2 years  on which extinguisher by means of hydraulically test pressure is 17.5kg/cm2 and is applied for 2.5 minutes.

Operation & Recharge of water type extinguisher

Operation 

 Carry the extinguisher to the place of fire. Check the tightness of the cap.Remove the safety clip or safety pin. Strike opr squeeze the operating head,keeping your head away from the trajectory of the extinguisher head.Direct the water to the seat of fire in a sweeping mode.


 Recharge 



After making sure that the vent holes are free .Unscrew the head. Unscrew the gas cartridge.Clean the container properly and refill it with pure water up to the marking.Add anti freezing chemical if required.Check the plunger for its service ability.Clean and grease if required.Screw a new CO2 cartridge on  to the head .Replace or screw the head tighten it. The recharging date should be written on  the extinguisher. Check the rubber hose    for its operational purpose.Blow through the hose pipe.

Construction of Water type extinguisher

These extinguisher are cylindrical in shape. Outer container is made of mild steel & treated for anti corrosion.Contains 9 ltrs of pure water.The outer container is pressure tested for 350 PSI. CO2 cartridge stored in the cylinder by coupling it to the operating head. Operating head which is with a plunger & striking knob or squeezing lever is screwed to the outer container. The knob is protected with a safety clip or safety pin to prevent accidental operations. There are three vent holes provided on to cap to allow the pressure to be released  by which explosion hazard of the extinguisher can be avoided.

Type of extinguishers

Basically five type of extinguishers & they are: 

Water type
 Form type
 Dry chemical powder extinguishers 
 CO2
 Halon type. 


                                                           Water type & form type DCP extinguishers are basically gas cartridge type.CO2 and Halon are stored pressure type. Every one must have the knowledge in construction ,operation of an extinguisher,maintenance /recharge of an extinguisher.


Water type extinguisher. 


                                                           The extinguisher will have an operating head ,it is punching type or squeezer type .The operation of both types are different but the operation will be same that a pin in the operating head is piercing the CO2 cartridge coupled to the operating head.Water type extinguishers are normally used in a Class A Fire.

Proportion of discharge

Water & Form -95%

Powder type & Halons - 85% 

CO2 - 75%
Delay in operation: 



                                Not more than 4 seconds should lapse between the operation of the control mechanism & commencement of the discharge from extinguisher.

Color of portable extinguisher:

                              Water type extinguisher  Signal red Form type extinguisher Pale cream  Dry chemical powder  French blue  Halogenated hydro carbon  Emerald green CO2 Black with silver neck .But in general all extinguishers are painted red.

Minor fire fighting appliances

                                                Fire fighting equipments come in the form of fire buckets, fire blankets or portable fire extinguishers which may be portable or wheeled to carry it to operate in a place of fire. These are called generally minor fire fighting appliance. 

 

Portable fire extinguishers.

 

 

                                              Fire extinguishers come in variety of types and sizes. the working principles of extinguishers are based on Gas cartridge & Stored pressure.

FIRE FIGHTING TECHNIQUES

The success or failier of the fire fighting will largely depends on : 

Fire protection arrangements provided.
Provision of the fire equipments & early warning devices.
Conducting training . maintenance of fire fighting equipments.
                                                        


                                                         We have classified the fire in to four classes.,now we can consider the fire into two type.Such as Major fire & Minor fire. 
                                                  Major fire fighting appliances.


                                                         There are fixed fire fighting installations like Sprinklers ,Dranchers,TOTAL FLOODING SYSTEM ETC.WHICH MAY BE INTEGRATED TO AUTOMATIC FIRE / OR SMOKE DETECTION .these kinds of the fire fighting appliances .These equipments will work automatically or can be created manually.