Contaminants typically enter a facility through one of four ways: Air, Water, Supplies / Ingredients and People. Over the next few months, we’ll highlight these vectors and discuss methods to help control them. For our first post in this series, we’d like to talk about contaminants entering through the air.
Ambient air may be contaminated with or carry significant levels of a variety of potentially harmful microorganisms. There are three major sources of such microbes: a) those arising from microbial decomposition of various substrates associated with particular occupations (e.g., "moldy" hay leading to hypersensitivity pneumonitis), b) those associated with certain types of environments (e.g., Legionnaires' bacteria in water supplies), and c) those stemming from infective individuals harboring a particular pathogen (e.g., tuberculosis). As far as building ventilation design is concerned, the greatest impact of any ventilation design would be on the airborne route of contamination. If there is no control system for incoming air to your facility, these contaminants can enter and distribute throughout your facility. Two of the most common air quality control systems are ail filtration systems and ultraviolet light disinfection systems.
The most common types of air filters used for air quality control are Minimum Efficiency Reporting Value (MERV), High Efficiency Particulate Air (HEPA) and Ultra Low Particulate Air (ULPA) filters. MERV ratings range from 1-20, with higher numbers offering better filtration. HEPA and ULPA filters roughly correspond with MERV ratings of 17-20. HEPA filters are rated to capture at least 99.97% of particles 0.3 microns (µm) while ULPA filters are rated to remove at least 99.999% of particles 0.1 micron (µm) or larger. These systems are used in many critical environments to prevent contaminants or particulates from entering, and are available from a number of companies. Related: ClorDiSys has validated the use of our chlorine dioxide gas to decontaminate Camfil’s Mobile Media Tester.
Ultraviolet light is a specific part of the electromagnetic spectrum of light that offers germicidal effects. Ultraviolet light is divided into UV-A, UV-B and UV-C rays. It is the wavelengths in the UV-C spectrum, specifically 265 nm, which offer the greatest germicidal potential. When a micro-organism is exposed to UV-C, the nuclei of the cells are altered due to photolytic processes. This process prevents further replication and causes cell death. As such, rather than trap pathogens and microbes like a filter, ultraviolet light kills them.
Ultraviolet light is typically placed in one of two locations in order to control pathogens within incoming air. One location is inline with the supply air ductwork, disinfecting the air as it travels past the UV-C lamp. Another application is using UV-C light to control organisms on the air handling system’s cooling coils. UV-C light has been shown to reduce biofilms and control biofilm growth on cooling coils. Biofilm growth on cooling coils has been shown to increase static pressure within the HVAC system which causes the system to work less efficiently to overcome that higher pressure. Controlling these biofilms, in addition to supplying cleaner air, maintains the system's efficiency which in turn allows it to run better and save the facility money. These have been shown to provide a cost savings greater than the cost of the UV-C system itself.
ClorDiSys offers the AirGlow™ as an in-duct ultraviolet light disinfection system that can be installed in any HVAC system. The AirGlow can help reduce and/or eliminate the growth of bacteria, mold and spores on supply and return airflow. Designed for continuous and long-term use, the AirGlow is constructed out of corrosion-resistant stainless steel and uses UV-C lamps with a lifespan of 13,000 hours (approx. 18 months). As air passes the quartz glass UV-C bulbs of the AirGlow, the travelling air is disinfected, and harmful organisms that may have been present are killed. It provides continuous disinfection without special attention or risk of exposure to people in rooms being handled by the ductwork.
Read more about the AirGlow here or complete this form for a quote. Contact ClorDiSys Solutions for additional contamination prevention products and services.
