Don't Rely on Bleach for Mold Remediation

Mold cleanup job mistakes: relying on bleach to kill mold.

Here we explain how as relying on bleach to kill mold is by itself an unreliable mold remediation procedure that is not recommended. The proper objectives of an effective mold remediation job are to remove moldy materials that can't be cleaned and to clean surfaces that can be cleaned.

Bleach, diluted bleach, or bleach sprays used in cleaning may be appealing but they are unnecessary, potentially dangerous (if you get bleach in your eyes), and the use of bleach tends to lead to improper and inadequate cleaning - if you substitute "spraying bleach" for actually cleaning or removing the mold your cleanup will not be successful.

Warnings about Using Bleach as a "Mold Medicine" to try to kill mold or prevent mold in buildings

Leaks at the window (photo at left) led to mold growth behind wallpaper as well as in the wall cavity.

Surface cleaning of the wall was ineffective and occupant complaints continued in this building until this moldy material was found and removed and leaks at the window were repairs.

The object of mold remediation is to clean, or remove, the majority of the mold particles (spores, conidiophores, hyphae, mycelia) from the target surface.

The operative word to fix in mind is to "clean" or "remove" the problem mold.

"Killing" the mold is not the correct objective

1. You won't kill all the mold with bleach
   
   First of all because our lab work shows that you're unlikely to kill all of the mold on a surface using bleach, unless you use it at a concentration and duration which is so strong that you're likely to completely destroy the "bleached" material,
   
   We have examined many surface and air test samples from cleaned buildings and "cleaned surfaces" that were sprayed with bleach and have ound that where sprays alone were used we could retrieve both "dead" but still toxic or allergenic mold spores and often also live and harmful mold spores that would support future mold growth in the building.
2. Second of all because even if you could "kill" every mold spore,
   
   you are at risk of leaving toxic or allergenic particles in place - they may be dead but often such "dead" spores still contain toxic substances.
   
   In this sense dead means that the spore, if landing on an otherwise friendly substrate, would not propagate or grow into a fungal body. But it may still be harmful if inhaled or gotten onto your skin or into a cut.
   
   See MOLD KILLING GUIDE for details

Our photo shows nice healthy black Stachybotrys chartarum spores collected from a "mold-killing bleach" treated surface in a building.

Finally, "mold removal" only works if you're cleaning a relatively hard, non-porous surface

 such as finished wood, painted metal, or plastic.

Soft materials like Sheetrock™ or drywall

 which have become moldy generally should be removed, the exposed surfaces cleaned, and then new drywall can be installed (after you've also corrected the reason for the mold growth in the first place).

Spraying anything

if spraying of fungicides or sealants is to be used in place of actual cleaning or removal of mold is an improper and inadequate practice which risks leaving a reservoir of toxic or allergenic particles in the building.

MOLD CLEANUP with BLEACH for details about using bleach to clean up or treat moldy surfaces.

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Continue reading at RELYING on OZONE to KILL MOLD or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• DISINFECTION of BUILDING SURFACES
• MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
• MOLD CLEANUP GUIDE- HOW TO GET RID OF MOLD - home
• MOLD CLEANUP - MISTAKES to AVOID
• MOLD KILLING GUIDE

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RELYING on BLEACH on MOLD at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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