No smoke without fire
01 November 2018
Prompt, expert techniques are required to successfully restore a property from fire and smoke damage, and both cleaning and decontamination should always be the primary considerations for all technicians involved. The British Damage Management Association (BDMA) explains
Cleaning is essential for reducing the corrosive action of smoke residues and controlling the potential of cross contaminating unaffected areas. Properties and all contents affected by smoke or fire damage need cleansing from toxins and unleashed chemicals from smoke particles, which could cause health problems if not removed and treated in a professional manner. It’s therefore imperative that cleaning is undertaken quickly, within the stabilisation phase, to mitigate damage and increase the likelihood of restoration over replacement.
No two fire or smoke damage incidents are the same. This is because the contaminants involved with smoke are entirely dependent on the materials burnt, fuel available, time-frame, temperatures, building construction methods and building materials. The circumstances, type of fire and affected materials will inform the appropriate response. This will involve a primary damage assessment, examining for burnt timbers, heat damage, initial wood swelling from water damage, and more. It’s essential that prior to a full assessment the health & safety aspects of the site are assessed and documented.
A qualified technician should lead the cleaning process. Their expertise can assure that they are able to take prompt action to reduce secondary damage. Secondary damage is damage that occurs after the incident, within the first few hours, days and weeks.
Typical examples of secondary damage are: Rusting/corrosion from acidic fire residues; swelling/distortion of timber from delayed drying; and mould growth/rot.
The extinguishing methods used should be carefully considered, as they could create secondary issues associated with water damage. With no ‘one-size-fits-all’ approach to cleaning fire and smoke damage, many methods are used, including pressure washing, air scrubbing/cleaning, steam cleaning, dry cleaning or thermal odour removal.
Fire/smoke incidents and their cleaning treatments can be distinguished as per below:
Low oxygen fires (slow burning)
- Strong odours which are difficult to remove from absorbent materials
- Deep-set residues to porous surfaces
- Run-lines on vertical surfaces due to condensation
- Wet cleaning techniques are required, alongside aggressive products for removal
- Prompt mitigation procedures required to minimise losses
High oxygen fires (fast burning)
- Items suffer from more thermal damage (scorching and distortion)
- Drier residues require dry initial removal techniques
- Affects numerous areas – including difficult to access places
- Smoke chains and cobwebs visible at high levels
- Voids/roof spaces may require treatment
- Odours often resemble item burnt (fish, meat etc.)
- Cannot be seen with naked eye
- Dismantling of fixed items within the fire area is generally necessary
- Initial odour removal required by air scrubbing or air cleaning
- Absorbent items may require ozone chamber treatments
Chloride residue fires
- Cause etching/discolouration to metals and plastics
- Testing is required of all areas within the property to ascertain the spread and degree of residue present and subsequent mitigation procedures
- Electrical and electronic items require immediate mitigation actions and essential post testing
- Treatments to surfaces to stop/restrict corrosion are necessary
- Cause build-up of acidic residues, creating corrosive acids which etch surfaces and textiles (if combined with air humidity, water from fire extinguishment or cleaning attempts)
- Prompt action is necessary to reduce surface acidity
- Odours are pungent and require several odour cleaning methods
- Climate control (dehumidifiers) must be installed at stabilisation phase
- Can leave deposits of oleophillic material (which discolour and stain easily), attracting particles of incomplete combustion to surfaces and textiles
- Residues are generally black and sticky
- Dry removal techniques are essential (absorption or suction) as the first step of restoration
- Absorbent materials may require several cleaning techniques
Benefit further from the BDMA’s training and advice on industry standards by becoming a BDMA member or associate. Find out more here: http://www.bdma.org.uk/membership-and-accreditation/