PPE/PPC – The Last Line of Defence – Part 2
In my last article in this series of Last Line Of Defence, I wrote about ‘Ensemble Thinking’ and the important issues of compatibility of different items of PPE/PPC. This becomes very useful when trying to identify the most vulnerable component or item of PPE.
Often this comes from a different item of PPE which is designed to provide protection from a different hazard to a different part of the body. A good example of this is in a structural firefighting ensemble, where the coat and pants primarily, but not exclusively, are designed to protect the firefighter from heat and flame exposure, while the SCBA is primarily, but not exclusively, designed to protect the respiratory system.
There is much work being done in Europe on the “Flame Engulfment and Drop Test” for Respiratory Protection Devices (RPD). Historically this ISO committee has been formed from a broad industry base and is a separate committee to ISO TC 94 SC14 for Firefighting PPE. We have had a liaison member reporting the progress from the RPD SC15 committee for some time. They deal with the safety standards for all the different types of devices across industry in general, that protect the respiratory system including SCBA, Powered Air and Filtered devices. Given the critical nature of this life support system for Firefighting, it is paramount that international safety standards are comprehensive and commensurate with the risk of our firefighting industry.
The past experience of melted components or harness strap failures, has led standards bodies to refine the “Flame Engulfment and Drop Test”. Case studies of harness failure after flame and or heat exposure, has seen the potential for the weight of the cylinder dislodging the mask, which could lead to just one breath of super heated air into a firefighters airway, with a potential tragic result.
Many of the rigorous tests on Firefighting RPD’s will ensure that we remain well protected. Part of the current testing is to not only look at challenging the various components which make up an RPD, but to ensure that it continues to supply air to the firefighter post exposure.
Some of the recent work in Geneva has seen a range of refinements to the “Flame Engulfment and Drop Test”. The B/A is donned onto a torso and head form, which records breathing. The operating B/A set travels along a rail into a heated compartment as a pre-treating test and is then returned to the burner area, where it is engulfed in flames. After this envelopment is completed, it is sharply dropped vertically on a slide, to test the security of the components, particularly the harness.
Tests so far have seen leading brands of B/A’s continue to supply air at the appropriate flow rate and pressure. Currently this is an important test to provide information to firefighters when they are considering issues of compatibility of their PPE/PPC. Additionally manikin style testing for all elements of PPE is valuable work, some of which is seen above.
There is much discussion in Europe about the issue of interoperability of SCBA fittings and components. This is a vital issue and not just in Europe, especially where two or more agencies work in conjunction on the same emergency incident site. Having compatible equipment is a must and even more critical in provincial areas of joint agency response where first response capability
is limited and backup is some distance away. Additionally it is critical at major incidents where logistically the volume of resources is always a challenge.
One associated item of interest is ensuring that any air hose line equipment from a remotely located air bank trolley, is tested to the same chemical testing as your Haz-Mat suits, because the air supply hose may be dragged through the spilled chemical.
One of the major challenges for standards makers comes with ensuring all the ancillary equipment used in conjunction with SCBA is compatible and remains fit for purpose in the same hostile environment. To that end the NFPA has been doing good work on electronic components associated with B/A, and improved high heat and flame resistance of many of the materials used on B/A sets.
Additionally they have tested for the robustness of the components of a set with a Tumble Test which was first required in NFPA 1982, 2007 Edition (Standard for personal alert safety systems (PASS). One of the critical issues for PASS and DSU systems is to ensure that their alert tone is not the same as the common tone of building smoke alarms which are used in your country. It quickly becomes difficult to manage the recovery of a “downed firefighter” if the intervention team cannot distinguish the difference between these tones or alerts.
Communication systems have become an integral part of the SCBA or firefighters PPE. So to for the telemetry used to monitor firefighters real time air usage, physical data and a range of other important data sets. The ability to devise testing equipment and regimes which are reproducible, credible and have clear pass/fail criteria, and harmonize those tests with others used for the other associated elements of PPC/PPE, is the continuing challenge for standard makers around the world.
Therefore it is important when purchasing PPE to not only seek that a given item passes your required standard, but also be able to gain as much detail from the test data as possible. While test houses need to test different types of PPE in different ways, the focus remains, that when these items of PPE are put together, they will perform to protect the firefighters from the same exposure.
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