Excelsius wet chem

[John Dragon]

One of our engineers brought in a used Excelsius 6 litre wet chem today.
The swivelling hose union to the valve had come apart upon discharge so the customer reportedly used the extinguisher on a fat fire without benefit of the lance, I.e. just a jet of chem from the valve.

Anyone heard of this before, and any comments on the safety of the customers actions?

[AnthonyB]

So it came apart at the valve - the obvious failure point is where the hose meets the plastic handle part of the lance -I've had a couple of post '97 TG series 2000 Foams fail where the hose is crimped to the plastic spray nozzle which then flies off like a baton round!

Any pictures?

I've not heard of a failure exactly like you describe before, wet chems are more susceptible to internal failures around the diptube union with the valve and the valve itself due to incompatibility of the chemical with the metal used and corrosion/oxidisation occurring.

The customer was very lucky - a jet based discharge would mix with the cooking oil, the water content turning to steam and ejecting the contents, although if you aimed it at the back edge of the cooking appliance so it would gently stream down across the oil (as you would do with the old foam branchpipe extinguishers on contained class B fires)you would be safer.

[The Reiver]

The ex-celsius water spray is doing the same during useage.
I have 3 examples of the spray nozzle end shearing off immediately at the point of the nozzle narrowing towards the female screw thread into the hose.
The kit is 3 year old. Poor plastic compound that can't take the pressure of a discharge is my only conclusion.

[The Reiver]

Aaaaaaaaaaaand as a side issue. It is noted that the discharge lance / wand is a fast disappearing item on a Wet Chem Extinguisher. Majority of kit now has just a standard spray hose attached. Reason being ?

To quote a manufacturer: "We could not get the extinguisher through its B rating with the wand".

I thought the wand was an integral safety aspect of the extinguisher so that you could get an angle above the frying vat and drop the medium in there. you are now relying on arcing a spray up and over the appliance in the hope of hitting something. Most of the contents will be wasted in the effort.


B rating on a Wet Chem.............what is the point ??

But then again what is the point of any BSI test ratings when they are carried out by super human, immortal beings that can put a 13A crib fire out with a wet lettuce, soggy sponge and a water pistol.
I pale in their shadows I do. They should all be working for the southern water authorities. No water shortage with those guys on your team 

[Psuedonym]

Tut tut, how cynical !! 

The reason for the disappearance of the wands is due to the manufacturers running out of ideas regarding how to house them along side the extinguisher body without it continually and annoyingly falling off and becoming a trip hazard.
Risk assessors are now provided with a tick box to check the wands location as waitressess, blinded by the towers of food dishes during busy periods, have reportedly been tripping over them as the extinguisher innocently sat in an egress point which often doubled as the restaurant MOE route as well as the servery outlet path.
The easiest solution was to remove the wands claiming lack of training merely led to user confusion regarding use of the wands. This is in the latest BS draft. Along with one or two other new bizarre plans.   

[TFEM]

I have 3 examples of the spray nozzle end shearing off immediately at the point of the nozzle narrowing towards the female screw thread into the hose.

We had the same problem with some Delta foam spray extinguishers manufactured in 2007, tested early due to suspicions about the internal lining.
The nozzles went almost as far as the discharge spray.
John

[AnthonyB]

I've had post 1997 Thomas Glover cartridge foams shoot the short plastic lance/nozzle off like rubber bullets before.

The loss of the lance actually in part is just us catching up with the US who dumped lances on Wet Chemical several years ago (NFPA 10: Standard for Portable Fire Extinguishers, 2002 Edition) after there was a concern that an operator could walk up to an involved deep fat fryer, and submerge the wand below the liquid surface prior to initiating discharge. Such an action (referred in some publications and presentations as subsurface injection) would cause the water content of the wet
chemical solution to convert to steam, expanding its volume at a ratio of 1750:1 instantly, resulting in an explosion of the burning grease.

Also with a wider use of ABF Foams and small sizes (2 litre, 600ml, etc) the need for a traditional spray nozzle to accomodate Class B use.

Finally it's cheaper - the same cylinder, valve, hose & nozzle can be used for 6 litre water, water additive, foam and Wet Chemical, just use a different screen print and fill!

Ex-celsuis stuff is comes from here http://www.winnerfire.com.cn/english/about.asp

Oddly despite owning several extinguisher manufacturers TYCO are a big user.

Delta (if it is the Delta Fire I am thinking of) have used Firex (now called FireFly) extinguishers for years & briefly before that an unkown Italian brand