History The first fire extinguisher of which there is any record was patented in England in 1723 by Ambrose Godfrey a celebrated chemist, It consisted. - презентация

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2 History The first fire extinguisher of which there is any record was patented in England in 1723 by Ambrose Godfrey a celebrated chemist, It consisted of a cask of fire-extinguishing liquid containing a pewter chamber of gunpowder. This was connected with a system of fuses which were ignited, exploding the gunpowder and scattering the solution. The carbon dioxide (CO 2 ) extinguisher was invented by the Walter Kidde Company (USA)in 1924 in response to Bell Telephone's request for an electrically non- conductive chemical for extinguishing the previously difficult to extinguish fires in telephone switchboards. It consisted of a tall metal cylinder containing 7.5 lbs. of CO2.

3 Co2 Extinguishers Naturally found in the atmosphere so there is no environmental impact. CO2 provides a heavy blanket of gas that reduces the oxygen level to a point where combustion cannot occur. CO2 gas has a high rate of expansion, which allows a fire protection system to work fast. Carbon dioxide a colorless, odorless, electrically non- conductive gas Reliable protection in sensitive area : With no residual clean-up Applicable to a wide range of fire hazards, effective on flammable and combustible materials and approved for Class A, B, and C hazards

4 Carbon Dioxide Suppression Automatic System Application: Flammable liquid storage areas Turbine driven generators Electrical areas Engine rooms CO2 systems consist of a fixed supply of carbon dioxide connected to a piping network for agent distribution. Temperature sensing controls permit the automatic injection of permanently piped carbon dioxide into areas to be protected. A total flooding system quickly extinguishes both surface and deep seated fire hazards by discharging the agent into an enclosed volume. The system usually includes warning alarms to alert personnel whenever carbon dioxide is being injected into an actuated area.

5 Example of a CO 2 high pressure system for one extinguishing zone: Consist of : 1.Alarm bottle with electrical actuator 2.CO2extinguishing agent bottle with pneumatic actuation 3.Manifold 4.Delay device 5.Extinguishing nozzle 6.Automatic fire detector 7.Fire detection and control panel 8.Visual warning device 9.Electrical alarm sounder 10.Pneumatic alarm horn 11.Manual release When the volume of co 2 to be stored exceeds about 2,000 kg we use co 2 refrigeration method to reduce storage pressure.

6 CO2 Suppression System Design Calculation 1 st Step: Determine the Hazard Group Difference hazard group required difference value of CO2 design concentration and flooding factor as shown in the table 3 2 nd Step: Calculate Room Volume & Surface Total Room Volume= L*W*h Total Room Surface= S.A of all faces Limit of Uncloseable Opening= (usually assume 10% of the total room Surface) 3 rd Step: Calculate The required CO2 Weight Weight of Required CO2 : W= (VxF1+O) M ( a) W=F2 x V ( b) Whereby: W-Weight of CO2 V-Volume of the Room F1-Volume Factor (Table 1) M-Material Conversion Factor (Table 2) F2- Flooding Factor (Table 3) O- 10% 0f total room surface area X(extra 5 Kg/m2) HazardDesign conc. % Flooding factor Elect. equipment Wool Sugar752.7 Table 3 (Hazard Factors) Volume of space (m3) Volume Factor(kg co 2 /m3) Calculated min.(Kg) V<

7 Adopt the highest value of W {max. of (a) or (b)} Apply 15% safety factor No. of 45 kg CO2 cylinder required = W/45 4 th Step: Sizing the CO2 Discharge Pipe Pipe and nozzle size are based on the designed flow rate W Kg CO2 per minute the flow rate Kg/min. So we got : Number of cylinders (45 kg). Design flow rate kg/min. Discharge pipe size mm. Reference of all tables : (BS 3506 : 4) MaterialMin. design Co 2 conc. (%) Material conversion factor Acetone311 Benzene371.1 Natural gas371.1 Diesel fuel341 hydrogen743.2 Methane301 Table 2: Minimum Carbon Dioxide Concentration Flow rate (kg/min)Pipe diameter (mm) Up to to to to to

8 Portable CO2 Extinguishers Application: Industrial Buildings Residential buildings Vehicles Administrative buildings It s portable device, carried or on wheels and operated by hand, containing an extinguishing agent that can be expelled under pressure for the purpose of suppressing or extinguishing fire. Are generally red, have a large nozzle (horn), in many capacities as table shown represented by Fike company. The cylinder must be mounted in the upright floor mounted position only, Horizontal mounting is not allowed.

9 Fire Extinguisher Size and Placement for Class B Hazards. Type of HazardBasic Min. Extinguisher Rating Max. Travel Distance to Extinguisher(m) Low5-B B15.25 Moderate20-B B15.25 High80-B15.25 Table Portable fire extinguishers used to comply with NFPA shall meet or exceed all the requirements of one of the fire test standards as ANSI/UL 711 and one of the performance standards as (Carbon Dioxide Types. ANSI/UL 154). Minimal sizes of fire extinguishers for the listed grades of hazard shall be provided on the basis of Table Fire extinguishers shall be located so that the maximum travel distances do not exceed those specified in the table used. Portable fire extinguishers shall not be installed as the sole protection for flammable liquid hazards where the surface area exceeds 10 ft2 (0.93 m2). Where personnel who are trained in extinguishing fires in the protected hazards are available on the premises, the maximum surface area shall not exceed 20 ft2 (1.86 m2). (ch.5) Reference of table : (NFPA 10)