Issue link: http://iaqnet.uberflip.com/i/637209
Fungicide: A substance that destroys fungi and yeast and/or fungal spores (on environmental surfaces) that may pose a threat to human health. Fungistat: An agent that inhibits the growth of fungi of economic or aesthetic significance that are not considered to be human health related (on environmental surfaces). This agent has no fungicidal claim. Bacteriostat: An agent similar to a fungistat in that it inhibits the growth of bacteria (on environmental surfaces) that is not considered to be human health related. Algaestats: An agent similar to a fungistat in that it inhibits the growth of algae that is not considered to be human health related. At this time, the EPA has not accepted any disinfectant, sanitizer or fungicidal products for use in the ductwork of HVAC systems. However, some of these products are accepted for use in other parts of HVAC systems. Those products which have been accepted by the EPA for use in the ductwork of HVAC systems include the following claims: n Fungistatic n Bacteriostatic n Inhibits odor-causing bacteria and fungi n Inhibits stain and damage-causing bacteria, fungi, and algae n Deodorizes n Inhibits fungi and algae n Cleaning (a non pesticidal activity; removal of contaminants) Antimicrobial products are available for the treatment of coils, drain pans and other related HVAC system surfaces. Refer to the EPA-accepted product label for specific directions for treatment of these surfaces. Typical use n The major use of antimicrobial products in HVAC systems is for the inhibition of microbial growth on hard surfaces within components such as air handlers, fans and duct interiors. n Disinfectant products may be used in coils, drain pans, and other parts of the air handler. n HVAC components that have been exposed to flood water or sewage contamination should be assumed to contain disease-causing organisms and should be disinfected prior to being placed back into service. Since no disinfectants are registered for use in air ducts, systems that have been exposed to contamination from floods, sewage, or similar biological contamination must be evaluated by a qualified individual prior to being placed back into service. Cleaning alone may or may not be satisfactory. Replacement of such duct sections may be necessary. n Products chosen must include label directions detailing use in HVAC systems and their components and those directions must be followed. Application method Products are generally applied through spraying, wiping or fogging. However, the application method chosen must be one that is in the label directions. Antimicrobials should only be applied after the surfaces have been cleaned. Surface soil or contamination can interfere with the efficacy of a product. Antimicrobial products are evaluated based on use pattern (locations of use) and application method for potential human exposure and risk. When using any antimicrobial product, follow the directions carefully and use the personal protective equipment as directed by the label. Pros Properly used, antimicrobials can help reduce the risk or incidence of future microbial growth. Cons Overuse of antimicrobial products can lead to needless exposure to chemicals. Failure to follow label directions can pose risks or result in ineffective product performance. In some applications it can be difficult to apply the product in a manner that ensures adequate coverage and dwell time, leading to ineffective product performance. EPA requirements All antimicrobial pesticides for use in HVAC systems are required to be registered by the EPA. Products without specific HVAC directions are not to be used on these surfaces. A product has only been evaluated based on the directions for use listed on the label. The product is likely not to be effective if used in incorrect amounts or for a different dwell time. Every pesticide label bears the following misuse statement: "It is a violation of Federal law to use a product in a manner inconsistent with its labeling." It means that if the product is used in a manner other than that which is directed by the label, such action may be illegal and put the applicator and occupants of the building at risk. The label will also include the following information: n Specific pest(s) against which the product is effective (meaning that the product has only passed the testing requirements for those organisms listed on the label). n Sites (homes, hospitals, etc.) and surfaces (e.g., cooling coil) to which the product may be applied. This means that the product may only be used at those sites and on those surfaces which are identified on the label.