Wednesday, May 25, 2011

CFD Smoke Divers SCBA (air pack)

One of the most dramatic differences in equipment/technology I observed in Copenhagen was the Smoke Divers' SCBA.
Yours truly wearing one of the Smoke Divers SCBA

Normal CFB firefighters used a very standard compressed air, composite cylinder, open-circuit SCBA, without any of the bells and whistles I've grown accustomed to. No PASS alarm, RIT connection, or Heads Up Display (HUD). 

The CFB "Smoke Divers" however, use a closed circuit SCBA which was actually designed for mine rescue operations. These packs enable firefighters to operate in an IDLH (Immediate Danger to Life and Health) for two hours! Two hours you say? They must be very heavy and cumbersome right? Nope. They're packs weigh slightly less then my Scott 45 minute SCBA, and are actually smaller in profile. 
 CFB Firefighter with Smoke Divers SCBA

How does that work you say? Well, I'll tell you. 
  1. 100% oxygen is supplied from a 1 liter cylinder at the bottom of the pack
  2. O2 fills a rubber lung in the middle of the pack
  3. O2 is breathed from the rubber lung and exhaled via the black corrugated lines 
  4. Exhaled O2 and CO2 go to the filter at the top of the pack 
  5. CO2 is filtered from the O2 using a dry chemical similar to lime stone
  6. Remaining O2 returns to the rubber lung to be breathed again 

The major problem with the SCBAs is that the filtering system relies on and exothermic chemical reaction (heat generating reaction) to remove the CO2. This means that after the firefighters has been wearing the pack for and hour they're O2 will start being hotter and hotter. This problem is compounded in a fire by the fact that the SCBA attracts and holds the radiant heat from the fire. 

Now every safety conscious firefighter is saying that is unsafe to be in a fire for an hour let alone two, what is the point of having a pack that last for so long? 

CFB has the Smoke Diving packs to fight tunnel fires, which may require firefighter to travel through a smoke filled environment for quite some time before actually engaging the fire. Smoke Diver's wear these packs for all firefighting operations to stay familiar with they're use. 

What I noticed when wearing one, was that since you're breathing from a non-pressurized source (the rubber lung) there isn't any sound with your breathing. This was simultaneously unnerving and really nice, nice because it was easier to hear what was going on outside of my mask, but unnerving because I didn't know if I was breathing without the familiar sound of my regulator giving me another shot of air. 

Smoke Divers SCBA with protective cover

Copenhagen Fire Brigade (CFB) 2011



                                                           
On May 3rd 2011 I traveled to Copenhagen, Denmark, to do three 24-hour ride alongs with different companies of the CFB. With a department history going back to 1687 (324 years) and modern European firefighting equipment/tactics, the CFB is a wonderful mix between tradition and innovation. 

H station (yes I took a photo of a photo) 

All of my shifts were out of the main “H” station, the watch tower is no longer in service, but the rest of the building is as alive as the day it was built. With a cobblestone courtyard, iron rings to tie the horses up to, and ancient diving helmets, one feels as though they re walking right into the past of the fire service.
                                For tying up the horses back in the day

                                 Old diving helmet hanging outside bay door

Chief Car 
During my first shift with the CFB I road with the “Chief in Charge” they’re command vehicle, which would respond to all the fires in Copenhagen.

On my second shift I was on the “H Engine Company” this would be equivalent to our Engine 1, in addition to being an engine company the H Company were all trained as smoke divers which I’’ get into later.

Pioneers' crane/fire truck

And on my last shift I road with the Pioneers/Engineers. Pioneers are the self-proclaimed badasses of the department, performing the operations which involve heavy equipment, i.e.: ventilation, extrication, technical rescue, SCUBA and water operations.