FR2722996A1 - FIRE EXTINGUISHING FOAM AEROSOL CASE - Google Patents

Abstract

The aerosol can for extinguishing fires by means of a fire-extinguishing foam. The invention relates to an aerosol can for extinguishing all types of class A, B or C fireplaces. The aerosol can contains a film-forming foaming solution AFFF or AR- AFFF and a non-flammable, non-halogenated propellant such as N2 or N20. The diffusion is ensured thanks to a valve emitting a vaporized or misted jet not conducting electricity. The aerosol can according to the invention is particularly intended for the public market for the extinction of domestic homes.

Description

1- 2722996

  FIRE EXTINGUISHING FOAM AEROSOL CASE

  The present invention relates to an aerosol can containing a foaming solution pressurized to allow the extinction of fire. In other words, the invention relates

  a new aerosol can application intended for extinguishing household fires.

  Domestic fires are class A, B, and C. The classes of fires are defined in the

French standard NF S 60-100.

Class A lights: examples:

  Office trash, curtains, carpet, fireplace, barbecue, ...

Class B lights: examples:

  Can of petrol or fuel oil, fryer filled with oil, household products,

... DTD: Class C lights: examples:

Town gas, propane, butane, ...

  The extinction of domestic homes is traditionally carried out by means of fire extinguishers

  portable characterized in the French standard NF S 61-100.

  The technical problem posed by these portable fire extinguishers is directly related to their difficulty of use. Indeed, these portable fire extinguishers were primarily designed to be used by users trained in this material, as is the case in high-risk industries. However, an uninformed person will hesitate before handling the extinguisher because they have NEVER used it before. However, it is recognized that the speed of intervention conditions success

  extinction and the extent of the damage.

  The technique of using the extinguisher is also important; a fire extinguisher is not

  fully effective only if used correctly.

  The variety and conditions of appearance of domestic fireplaces further increase the difficulty of using these portable fire extinguishers, the extinguishing agent having

different characteristics.

  The powder extinguisher discharges quickly and completely: one-go application. Its application technique is difficult and does not leave the right to an incomplete extinction because

otherwise the fire starts again.

  Indoors, the powder cloud is blinding and suffocating and can increase the risk if the

outbreak is not under control.

  The use of the powder is therefore not recommended in a closed room.

  The halon extinguisher has an inhibiting action and is ineffective on class fires

  A. In addition, halons generate dangerous corrosive vapors during combustion.

  The C02 fire extinguisher is difficult to use because it can cause serious burns if you put your hand on the projection nozzle. Its effectiveness is poor on class A fires. -2- The water or additive water extinguisher with full jet has drawbacks because of the

  risk of electric shock in a house, the full jet being conductive.

  The spray water extinguisher extinguishes Class A fires. It has disadvantages over Class B fires. Use on a fryer with boiling oil can cause projections with severe burns to the speaker. The additive water spray extinguisher is applicable to class ABC fires even in

presence of electrical sources.

  It is however penalized by its lack of maneuverability because it is heavy: 10 or 15

  kilograms for all water extinguishers or water additives.

  In conclusion, the technical problem posed is the difficulty of using portable fire extinguishers. This difficulty is due to: - their principle of commissioning - their application technique - their weight

  1 5 - the various drawbacks specific to each extinguishing agent.

  There are also aerosol cans on the market containing halons. As it was

  mentioned above in the description, these products act only by action

  inhibiting and not suitable for class A fires. The invention makes it possible to remedy the drawbacks mentioned since it is based on the use of a

  2 0 aerosol can spraying a versatile ABC fire extinguisher.

  The only extinguishing agent meeting these criteria is the AFFF aqueous foaming solution.

  The AFFF additive allows to control ABC type fireplaces. It forms an aqueous insulating film

  when the foam settles on the hydrocarbons.

  The AR-AFFF additive allows the extinction of polar fires (acetone, alcohols ,.

  ) ... DTD: 2 5 AFFF: Aqueous Film Forming Foam AR-AFFF: Alcohol Resistant AFFF A propellant gas usable in aerosol and ensuring a discharge pressure must be used

  sufficient to guarantee good efficiency.

  The existing technique in the additive water extinguisher consists in striking a cartridge of C02. The tank then rises to a pressure of 35 to 40 Bar at 20 C, which allows

  ensure a discharge pressure of at least 8 Bar.

  Our first tests with CO2 aerosol demonstrated the impossibility of using the existing technique. The aerosol canister does not withstand internal pressures greater than Bar at 20 C. At this pressure, the discharge of the solution is weak, the foam liquefies

  3 5 quickly and the case does not fully discharge.

  The hydrocarbons - propane, butane - commonly used in aerosol are not suitable for

  our application because they are flammable.

  CFC substitutes are halogenated gases and exert an inhibiting action on class BC fires. The aerosol tests are conclusive, but the solution did not satisfy us because this type of gas is far too controversial for its impact on the environment. Unable to use liquid gases - butane, halogenated - we tried to combine

compressed gases.

  The innovation consisted in associating with the foaming solution another gas: protoxide

nitrogen: N20.

  This gas is very little used in the aerosol. It does not relax well, has no solvent power and

is hardly miscible in the liquid phase.

  We have found that N20 behaves very well with the foaming solution. This can absorb up to 65% of its own volume in N20, which allows it to rise to a pressure of around 8 Bar. The discharge tests confirmed the excellent association of the two liquid gas phases. The foam produced is of good quality and the housing is completely emptied. We then tested nitrogen in the same way: N2. The results were identical to

those observed with N20.

  On the strength of these results, we have carried out a number of extinction tests described in

The examples below.

  The following commercial products are used: - Light - Water FC 3041, an AFFF additive manufactured by 3M and usable as a 1% mixture

in water.

  - UNISERAL AF 12 3%, an AFFF additive manufactured by CRODA UNISER and usable at 3%

in water.

  - UNISERAL AF 30 PN, an AR- AFFF additive manufactured by CRODA UNISER and usable at

6% in water.

  These solutions are added with a corrosion inhibitor to protect the aerosol can.

  Tests are carried out on stoves as described below: In a 1 liter aluminum aerosol can, a foaming solution is introduced according to recipes 1, 2 or 3. Then pressurized by introducing nitrogen or protoxide

  of nitrogen to obtain a pressure at 20 C from 5 Bar to 8 Bar.

  The aerosol can is then fitted with a spray valve. The tests are carried out according to standard NF S 61-900. The home control times are observed at 90%, the time

  total extinction, then possible re-ignition after 5 minutes.

4 2722996

  RECIPE USED FOR FIRE TESTS

RECIPE 1 2 3

WATER 59.3 58.1 56.3

CORROSION INHIBITOR 0.1 0.1 0.1

N2 40 / /

N20 40 40

FC 3041 0.6 / /

UNISERAL AF 12 3% / 1.8 /

UNISERAL AF 30 PN 3,6

  The values are expressed as a percentage by weight.

  Type 3A hearth We place on a metal base 250 mm high, 900 mm wide and 30 cm

  length a stack of wooden bars in Pinus Sylvestris containing 15% humidity.

  These bars have a square section of 4 cm.

  These bars are alternated in 14 layers regularly spaced 6 cm apart. The longitudinal bars are 50 cm, the others 30 cm. 3 bars of 50 cm are placed per longitudinal level. A rectangular container 40 cm long, 60 cm wide and 10 cm deep is placed under the stack. We fill this tank with water 3 cm high, then pour 8 liters of petrol without

2 0 lead.

  We light the gasoline, after 2 minutes of combustion, we remove the tank. We let the wood burn

  another 6 minutes, then we start the projection by moving to get the best result.

  Type 8B hearth A sheet steel tub 56 cm in diameter and 10 cm deep is used. We introduce

  2 5 8 liters of fuel. We turn on and let burn 1 minute, then we start the projection.

  Type 5B hearth A sheet steel tray 45 cm in diameter and 10 cm deep is used. Liters of fuel are introduced. We turn on and let burn 1 minute, then we start the projection.

TEST RESULTS

TYPE OF FIREPLACE 3A 8B 5B

RECIPE 1 2 3

  HEPTANE ETHANOL ESSENCE FUEL 9o0%

LEAD FREE + PIN

PRE-COMBUSTION TIME 8 '1' 1 '

FIREPLACE CONTROL 90% 10 "15" 20 "

100% EXTINCTION 30 "40" 50 "

RE-LIGHTING AFTER 5 'NO NO NO

  Extinguishing is carried out quickly on solid fires (wood), hydrocarbon fires (heptane) and polar solvent fires (90% ethanol). We note the absence of re-inflammation

after 5 minutes.

  The handling of the aerosol can is extremely simple, a simple pressure of the finger on the valve releases the product. The generalization of its use means that EVERYONE knows how to use an aerosol. Its low weight facilitates intervention. A suitable valve allows foaming of the solution to the discharge. Spraying by dissociating the aqueous jet avoids the

electrical conduction.

  The extinguishing agent is an aqueous solution with an AFFF or AR- type foam concentrate

  AFFF complies with standards NF S 60-210, NF S 60-220 (AFFF) and NF S 60-225 (AR-AFFF).

  The aerosol can according to the invention makes it possible to ensure: - a rapid means of intervention because it is light and simple to use for everyone - fire extinguishing efficiency on domestic households of all types because its foam is versatile ABC.

  - a possibility of use even in the presence of electrical sources because the jet is vaporized.

  The invention describes a product which, put on the market, will offer a new, simple means

  and effective for extinguishing all types of household fires.

6- 2722996

Claims (4)

  1 - Aerosol can to extinguish a fire, characterized in that it contains a multi-purpose aqueous foaming extinguishing solution ABC and a non-flammable, non-halogenated propellant. 2 - aerosol can according to claim 1 characterized in that the propellant is nitrogen N2 or nitrous oxide N20.   3 - aerosol can according to claims 1 and 2 characterized in that the aqueous solution   foaming extinguisher is of the AFFF film-forming or AR-AFFF film-forming type.   4 - aerosol can according to claims 1, 2 and 3 characterized in that the valve emits a spray or mist.