miércoles, 28 de agosto de 2013

Bacteria in Drinking Water

News | August 14, 2013
  Bacteria In Drinking Water Are Key To Keeping It Clean

Research at the University of Sheffield, published in the latest issue of Water Science and Technology: Water Supply, points the way to more sophisticated and targeted methods of ensuring our drinking water remains safe to drink, while still reducing the need for chemical treatments and identifying potential hazards more quickly. The research team, from the University of Sheffield's Faculty of Engineering, studied four bacteria found in the city's drinking water to see which combinations were more likely to produce a 'biofilm'. Biofilms are layers of bacteria which form on the inner surfaces of water pipes. "Biofilms can form on all water pipes and as these are usually non-harmful bacteria, they don't present a problem," explains lead researcher, Professor Catherine Biggs. "However, biofilms can also be a safe place for harmful bacteria such as Escherichia coli or Legionella to hide. If the bacterial growth is too heavy, it can break off into the water flow, which at best can make water discoloured or taste unpleasant and at worst can release more dangerous bacteria. Our research looks at what conditions enable biofilms to grow, so we can find ways to control the bacteria in our water supply more effectively." Funded by the Engineering and Physical Sciences Research Council, the research isolated four bacteria from water taken from a domestic tap: two were widely found in drinking water everywhere, one was less common and one was unique to Sheffield. The researchers mixed the bacteria in different combinations and found that, in isolation, none of them produced a biofilm. However, when any of the bacteria were combined with one of the common forms, called Methylobacterium, they formed a biofilm within 72 hours. "Our findings show that this bacterium is acting as a bridge, enabling other bacteria to attach to surfaces and produce a biofilm and it's likely that it's not the only one that plays this role," says Professor Biggs. "This means it should be possible to control or even prevent the creation of biofilms in the water supply by targeting these particular bacteria, potentially reducing the need for high dosage chemical treatments." Domestic water supplies in the UK are regularly tested for levels of bacteria and, if these are too high, water is treated with greater concentrations of chlorine or pipe networks are flushed through to clear the problem. However, the standard tests look for indicator organisms rather than the individual types which are present. Testing methods being developed by the Sheffield team – as used in this research – involve DNA analysis to identify the specific types of bacteria present. "The way we currently maintain clean water supplies is a little like using antibiotics without knowing what infection we're treating," says Professor Biggs. "Although it's effective, it requires extensive use of chemicals or can put water supplies out of use to consumers for a period of time. Current testing methods also take time to produce results, while the bacteria are cultured from the samples taken. "The DNA testing we're developing will provide a fast and more sophisticated alternative, allowing water companies to fine tune their responses to the exact bacteria they find in the water system."
 SOURCE: University of Sheffield

viernes, 9 de agosto de 2013

SICK BUILDING SYNDROME

Indoor Air Quality: Clearing The Air By Ronnie Garrett Ever gotten complaints from building occupants that they felt better before they arrived at work and again after they left? And it wasn't because they disliked the job but because the building was making them sick? There's a name for it — it's called sick building syndrome. In this condition, building occupants complain of symptoms such as sensory irritation of the eyes, nose and throat; neuro-toxic or general health problems; skin irritation; nonspecific hypersensitivity reactions; and odor and taste sensations. These symptoms are often pinned to flaws in the heating, ventilation and air-conditioning systems. Other factors include contaminants produced by the off gassing of building materials, volatile organic compounds (VOCs), molds, byproducts of office machinery, light industrial chemicals and more. While the long-term affects of exposure remains an emerging science, there is much custodial workers can do to reduce their exposure, and that of others, by improving indoor air quality (IAQ). There are three primary means of exposure: Inhalation, ingestion and skin contact. When custodial managers consider all three routes, they expand their thinking to all factors that might impact IAQ. "Many times people think indoor air quality is only about chemicals and VOCs. But when you think of it more broadly in terms of what people can inhale, ingest or touch, it's also particles, dust and other contaminants," says Steve Ashkin, president of The Ashkin Group, Bloomington, Ind. "There are three basic things people have to be worried about: Chemicals, VOCs and dust particles, especially the really small ones which are tiny enough to inhale deeply into the lungs." Stop It At The Source According to Allen Rathey, president of The Healthy Facilities Institute (HFI), Boise, Idaho, there are three main ways to improve IAQ: (1) Stopping contamination at the source, (2) Better ventilation, and (3) Cleaning the air itself. The best approach, he says, is to stop contamination at the source. He likens airborne contamination to an oil spill. Once oil gets into the environment, it quickly dissipates and spreads. "It's better to stop an oil spill before it starts, and it's the same with air contamination," he says. "By the time you get to step two or three, you're at the tail end of contamination." Stopping contaminants at the source requires a solid understanding of what the sources of contamination are. For example, consider the contaminants walked in on a person's shoes. These particles include dust generated by industrial facilities, pesticides and more, which is present in soil and on city streets and sidewalks. "If you keep that dust from coming into the building, you stop one source of contaminants," says Rathey. How might this be accomplished? By washing sidewalks and parking lots near building entrances, then putting large walk-off mats inside and outside every doorway. This matting must allow a sufficient number of steps to occur in order to ensure dust falls off shoes and onto the mats. "We can keep a lot of nasties out of the air just by making sure our cleaning program has a sidewalk maintenance component and great entrance matting," Rathey stresses. Suck It Up Next is to make sure equipment actually removes, rather than redistributes dust and other contaminants. Vacuum cleaners deserve primary consideration, says Carpet and Rug Institute (CRI) President Werner Braun. "There are vacuums out there that blow stuff back into the air because their housing is poorly designed," he explains. CRI simplifies vacuum selection through its Seal of Approval Program. This program rates vacuums on soil removal, dust containment and safety to carpet surfaces. "The Seal of Approval is the only quantifiable testing program for vacuums in the world," says Bethany Richmond, CRI communications manager. "We test vacuum cleaners to see if they work, are low emitting and don't destroy the carpet." When targeting IAQ concerns, Braun recommends cleaning operations choose vacuums with CRI Seal of Approval Gold certification. This certification ensures a vacuum removes and holds particles as small as 35 micrograms. And that's a good thing, says Ashkin, who points out that it's the fine particles (smaller than 0.3 microns) that humans inhale deeply into their lungs. "If you select a vacuum that has been evaluated in this way, you know that you are keeping the dust you pick up inside the vacuum," Rathey says. "You need a vacuum that's going to remove more and release less." Ian Grieg, CEO of Daniels Associates, in Phoenix, also recommends walk-behind vacuums or walk-behind sweepers for hard surfaces, as well as carpets. "Other countries have been vacuuming their hard-surface floors since the 1980s," he says. "We still don't vacuum hard-surface floors and that's one of the largest causes of poor IAQ because dust mops just throw particles into the air." But if this equipment — be it high-quality walk-behind, upright or backpack vacuums — is improperly maintained, it can contribute to IAQ concerns rather than address them. Vacuums use airflow to suck up particles but if clogged filters and nearly full bags reduce airflow, then fewer particles are picked up. "The beater brush is no longer driving dust into the vacuum as much as it is pushing it into the air," Rathey adds. Grieg says proper vacuum maintenance is a common problem across the custodial industry. Cleaners need to be taught to use high-filtration bags and change them regularly, he says. "The rule of thumb is to empty bags when they are half full, but manufacturers may recommend changing them when they are half, two-thirds or three-quarters full," Ashkin says. "It's never when they are so full they cannot hold anymore." A comprehensive carpet care program also improves indoor air quality. Carpets should be vacuumed daily and shampooed one to four times a year, says Grieg. When shampooing the carpet, make sure carpets dry out within 24 hours to keep mold issues at bay. "Mold and other organic materials require moisture to grow," Ashkin explains. Wipe It Up When dusting with cloths or mops, it's best to go the microfiber route. "Cleaning operations need microfiber wipes for all dusting, damp wiping and damp mopping," says Grieg. But heed this warning: Not all microfiber is created equal, Ashkin advises. No standards exist to ensure microfiber products meet exacting specifications. Cleaning operations need high-quality microfiber products that capture fine particles as opposed to cheap ones that do little more than flick dust into the air. "Look at the product's weight," says Ashkin. "There is a correlation between the weight of the cloth and the quality." And pick the right microfiber for the job. Differing microfiber blends exist and some do a better job with specific tasks than others. "The product will vary whether they are doing dry dusting or wet cleaning," Ashkin says. "They need to use the right microfiber for the application." Chemical Selection Using the wrong cleaning chemicals also can adversely impact air quality. It's important for cleaning operations to carefully weigh their chemical options and select environmentally preferable products, Ashkin says. "We should make an effort to minimize the VOCs in our cleaning products; we should not be contributing to the problem," he adds. Go with fragrance-free products and weigh disinfectant choices carefully, advises Rathey. "These products use petrochemicals and they are very suspect in contributing to IAQ problems," he says. "Quats, for example, have been associated with asthma." Sanitizers and disinfectants also contribute to healthier environments so they do have their place in cleaning, but their harmful affects can be mitigated by how they are used. For example, an aerosol disinfectant adds chemical to the air, but a squeeze bottle solution, where cleaners squeeze a stream directly onto a cloth, can alleviate this problem. Apply these products with a microfiber cloth or mop and IAQ improves again because custodians use less chemistry to clean. "Microfiber allows the use of less corrosive chemistries because it physically removes contaminants," says Grieg. Training And Teamwork "Training is the key to improving IAQ," adds Ashkin. Cleaners need to be taught to select the right product and equipment for the job and to use it correctly. At Daniels Associates, every spec includes a task number, the name of the task, the types of chemicals and equipment needed to perform the task and the results to be expected. "Cleaners need to be taught how to use chemicals and how to use equipment; equipment is a lot more technical than it used to be," Grieg emphasizes. "In the old days the equipment custodians used on the job were the same tools they used to clean at home. It's different now." Teaming with facility managers to ensure heating and cooling systems work with cleaning operations, rather than against them, also improves IAQ. "Why aren't cleaning folks talking with the people who take care of the heating and cooling systems?" Rathey asks. "If we're going to have a seat at the table of healthy indoor environments, we have to understand what's going on in the buildings regarding air flow and heating and cooling systems."

ODOR CONTROL


 

How To Remove Odors From Facilities

 

By CleanLink Editorial Staff

 

 

SPONSOR LINKS:

Complete Room Deodorizing

 

Do fresheners actually kill odors and/or bacteria in the air? Can you explain the science of how this works?

McGuire: Most fresheners do not “kill” anything unless they are part disinfectant. They are simply a cover-up for the foul odor. A registered disinfectant with the proper claims is needed to kill bacteria and generally needs to be applied at the odor source to be effective. The odor itself is caused by molecules that have the ability to emit a vapor. These molecules are generally created by the bacteria. As these molecules become airborne they emit a vapor that hits the olfactory system, allowing people to then identify it as a pleasant or foul odor. To eliminate the odor, you need to choose a product that attacks the odor molecule.

 

Malik: It depends on the product formulation and its claims. An air freshener is a product designed to mask or remove unpleasant room odors.  If it is designed to mask odors only, it will overcome a malodor by overwhelming it with a stronger odor for a period of time, but it will not break the malodor down.

If an air freshener is designed to break down malodors, it will contain odor counteractants in addition to fragrance. The odor conteractants neutralize the malodor by breaking down its molecules into the air. An air freshener with odor counteracts is the best solution for a facility with offensive malodors such as smoke and rotting food that should be removed from the air.

An air sanitizer can reduce airborne bacteria making the air you breathe healthier and cleaner. The simplest definition of how it works is a molecule from the air sanitizer attaches to a bacteria molecule and causes it to become inert.

 

Ferris: Let’s take urine odors – one of the toughest cleaning professionals face. Urine odor comes from naturally occurring bacteria and uric acid crystals (crystalized urine residue). Porous damp surfaces like grout host the bacteria, which feed on urine. Uric acid crystals often stay trapped in these porous surfaces and release strong odors as the bacteria consume the urine. Humid conditions or rewetting the surface can reactivate odors. The only real way to completely eliminate odors – not just mask them – is to eliminate those naturally occurring sources of odor.

Daluga: Ideally, "clean" smells like nothing at all, and thusly, custodial executives should seek odor solutions that don't employ phony fragrances that simply cover up odors.

 

Can you over freshen when it comes to odor control? Is there such a thing as too much of a good scent?

McGuire: Of course. The best policy is to use a technology that eliminates not masks the odor. Masking is the blending of two different odors that can become just as offensive as the odor itself. Once the odor is eliminated you can use a scent to freshen the air.

 

Malik: Air fresheners formulated with odor counteracts are the optimal solution to both break down and neutralize malodors and leave a fresh scent behind. Without the odor counteractant, an air freshener masks the malodor by overwhelming it with a stronger odor, but does not neutralize the malodor.  When using multiple cleaning or odor control products, it’s ideal to ensure the fragrances complement other scents in the area to create uniformity. Competing fragrances contradict each other and can become unpleasant.

Malik: It’s important to understand the size of the area that needs odor control coverage, and match this to your system of choice, along with the supplier’s cubic foot recommendation. When continuous and consistent odor control is desired, the optimal delivery solution is a wall-mounted dispenser. Typically metered aerosols cover larger cubic feet and deliver higher doses of continuous fragrance vs. passive air systems or fan systems and gel cups. Passive air and fan dispensers disperse neutral and low fragrant oils and typically have a lower coverage area than a metered aerosol. These examples of wall mount dispensers that deliver continuous odor control coverage are great solutions for common areas such as lobbies, break rooms, restrooms, hallways and conference rooms.

Liquid and hand held sprays are good solutions for spot treatments to supplement a wall-mounted dispenser program that offers continuous odor control and/or air sanitizer benefits.

 

Daluga: A sound odor management strategy employs a number of different delivery methods for odor control products. Use of a passive solution, such as a gel that works using ambient airflow, will address odors 24/7, while sprays will address odors immediately on an at-need basis. Other products, such as air and surface liquids or laundry additives, are designed to address specific odor issues at their source (mop buckets, wash loads, etc.). Indeed, each delivery method has a place in a sound odor management strategy.

 

 

 

Some facilities are actively working towards promoting green and sustainable initiatives. Where do air fresheners fit into that type of program?

Daluga: There are myriad odor control products on the market, but very few that use natural ingredients and fit under a "green" or "eco-friendly" heading.

 

Malik: While some cleaning product categories are rated green by third-party certifiers, there are no green certification standards for air fresheners. Even without third party certification, air fresheners can fit into green and sustainable initiatives. The optimal system will depend on the facilities odor control needs and goals of the sustainable initiative. For example, passive air care systems that offer low VOC continuous air freshening without the use of batteries or any power source, or metered air care systems that offer extended battery and odor control refill life.

How do odors (good or bad) impact the perception of a facility and it’s custodial crew?

McGuire: Foul odors give the impression that the facility is dirty. Thus, a process that is designed to “eliminate” not “mask” odors is essential to provide an optimal environment. Masking a foul odor can be tricky. Facility managers need to be careful on which fragrance they choose. Not all occupants like the same fragrance and in some cases masking can make matters worse.

 

Malik: A building occupant’s first impression of cleanliness is not necessary what they see, it can be what they smell.

Fragrance has a powerful effect on human behavior. Our sense of smell can evoke strong emotional reaction and influence behavior. Facility odors, good or bad, can shape the perception of how a facility is run, and how much the facility management cares about its customers. 

Pleasant fragrances can make us feel at home, brighten our moods, deliver a sense of calm and wellbeing, or increase alertness. Foul odors, even when isolated, can leave a negative perception of the entire facility, from the custodial crew to general management.

Customers or building occupants can associate foul odors with unsanitary and unsafe conditions. Similar to odors such as smoke or gas, foul odors typically trigger us to take an immediate corrective action, such as leave the establishment.

 

Daluga: When it comes to cleanliness, perception really is reality and a foul odor immediately raises eyebrows. Likewise, when a facility smells strongly of fragrances and perfumes, there's a perception that something is being covered up — there are odors being masked by other odors.

 

Ferris: Restrooms can certainly impact consumers’ perceptions of businesses, and as a result, also impact their bottom lines. According to a survey, three in four American consumers are disgusted by urine odors and urine stains in public restrooms. Of those surveyed, two-thirds would refuse to patronize business establishments such as restaurants or hotels with unclean restrooms and more than half would likely review a business more negatively (online or offline) based on whether the restroom was clean. Research from Harvard Business School found that Yelp reviews can have a five to nine percent effect on business revenues, meaning bad reviews can translate to lower profits. Additionally, the majority of parents surveyed (70%) say a school’s restroom reflects the quality of the school, its staff and its teachers.

 

 

Restroom odors are common, but what other areas of the facility should custodial managers focus on odor control?

McGuire: It is wise not to overlook kitchen areas, lunch rooms, break rooms, smoking areas, laundry, hallways and the always present dumpster. These are all areas that can cause problems.

 

Malik: Common areas such as lobbies, break rooms, conference rooms, hallways, and locker rooms are examples of additional areas where odor control solutions such as air fresheners and air sanitizers can improve facility image, customer experience, and protect customers/employees from the spread of germs. 

 

Daluga: A good odor management strategy addresses every aspect of a facility: certainly the restrooms, but also lobbies and common areas, offices and meeting rooms. Anywhere there's people, food, etc., there's likely to be smells that someone will find unpleasant, and it's crucial to have a strategy in place that addresses odors before they become an issue.

 

 

 

 

 

Contributors:

Michael McGuire

President

Thornell Corporation

Smithville, Mo.

 

Beth Malik

Director of Marketing

Amrep, Inc.

Marietta, Ga.

 

Amanda Daluga

National Sales Manager

OMI Industries/Fresh Wave IAQ

Long Grove, Ill.

 

Brad Ferris

Senior Public Relations Manager

Clorox Professional Products Company

Oakland, Calif.

 

posted on: 8/2/2013

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GREEN CHEMICALS

The Green Seal certification is granted by the organization with that name and has a great number of members contributing with the requirements to pass a raw material or a chemical product as "green". Generally for a material to be green, has to comply with a series of characteristics like: near neutral pH, low volatility, non combustible, non toxic to aquatic life, be biodegradable as measured by oxygen demand in accordance with the OECD definition.
Also the materials have to meet with toxicity and health requirements regarding inhalation, dermal and eye contact. There is also a specific list of materials that are prohibited or restricted from formulations, like ozone-depleting compounds and alkylphenol ethoxylates amongst others. Please go to http://www.greenseal.com/ for complete information on their requirements.
For information on current issues regarding green chemicals, see the blog from the Journalist Doris De Guzman, in the ICIS at: http://www.icis.com/blogs/green-chemicals/.
Certification is an important — and confusing — aspect of green cleaning. Third-party certification is available for products that meet standards set by Green Seal, EcoLogo, Energy Star, the Carpet & Rug Institute and others.
Manufacturers can also hire independent labs to determine whether a product is environmentally preferable and then place the manufacturer’s own eco-logo on the product; this is called self-certification. Finally, some manufacturers label a product with words like “sustainable,” “green,” or “earth friendly” without any third-party verification.
“The fact that there is not a single authoritative standard to go by adds to the confusion,” says Steven L. Mack M.Ed., director of buildings and grounds service for Ohio University, Athens, Ohio.
In www.happi.com of June 2008 edition, there is a report of Natural formulating markets that also emphasises the fact that registration of "green formulas" is very confused at present, due to lack of direction and unification of criteria and that some governmental instittion (in my opinion the EPA) should take part in this very important issue.