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A healthier dose1st of July 2011
A chemical dispensing system may require some initial outlay, but do the safety and sustainability benefits of an automated dosing system outweigh these set-up costs? Ann Laffeaty finds out.
Few would argue that a chemical dispensing system makes sense from a safety and sustainability point of view. Any system that avoids human contact with neat chemicals – while also minimising the risk of those chemicals being used in higher concentrations than necessary – has to be preferable than the traditional 'glug glug' method of dispensing.
And where chemicals are dosed manually by employees the margin for error is high. Operatives typically add more of the chemical than is actually required to ensure that the solution is strong enough to work.
Furthermore, cleaning solutions that are too concentrated could represent a potential health and safety risk to staff while also leading to excess chemical discharge into the water system. They may also be less effective than solutions that have been diluted to the correct degree.
But do such safety and sustainability benefits outweigh the financial implications of a chemical dosing system? Or is cost still king in today’s difficult economical climate?
In fact according to international marketing executive of Brightwell Dispensers Suzanne Gardent, traditional dispensing methods have cost implications of their own.
“The glug-glug method is an expensive, dangerous and non-accurate way of dosing chemicals into water,” she said. “There is no way of knowing how much of the chemical you should add to the mix so there is inevitably a risk of either under- or overdosing.
“The problem with underdosing is while you may think you're sanitising a surface, you're not - so there’s a risk of propagation of bacteria. And the problem with overdosing is an economical one since you may actually be throwing away any of the savings you were making by buying concentrates.”
She adds that dosing systems present a lower risk of spillage since the chemical passes through a pump rather than being handled manually. “With some systems – such as our own SuperC system - the chemical can actually be locked inside the dosing system and there is a time delay to help prevent the risk of overdosing,” she said.
Where super-concentrates are used in place of diluted products, argues Gardent, fewer deliveries are required which leads to lower freight costs and consequently less paperwork, which can result in further financial savings. Meanwhile other sustainability benefits include lower transport emissions and less waste packaging. And these advantages easily offset any financial implications for the customer, according to Gardent.
“We sell our dosing systems to chemical companies who usually provide our dispenser free to their customers,” she said. “They can then install it on the wall and the customer is locked into a contract for a specific period.”
Brightwell’s SuperC Chemical Concentrate dosing system is available in bottle, bucket and sink versions. It can be placed anywhere on a wall and requires no electricity or water source, says Gardent.
She claims that customers are slowly warming up to the idea of sustainable solutions, although safety awareness is generally more widely considered.
“Most customers have cost concerns but tend to feel that if a solution can also help the environment, then why not?’” she said. “It also depends on the market. Concern for sustainable equipment is growing in Germany and France, but in the UK customers are still mainly concerned with cost.”
Vice president marketing of Dema Engineering Dan Gillespie agrees that cost has always been a key driver for customers. However, he claims safety and sustainability are increasingly being cited as reasons for switching to dosing equipment.
“More and more people are willing to pay extra for products and systems – particularly if you can quantify the safety and sustainability gains,” he said.
According to Gillespie the benefits of dosing over glug glug mixing are directly related to accurately diluting the product and minimising exposure to concentrated chemicals. “Accurate dilutions avoid exposing employees to potentially harmful chemical concentrations while ensuring surfaces are left cleaner with no slippery or potentially harmful residue,” he said. “Accurate dilutions also minimise the environmental impact of the used solution in the water stream, while the super-concentrating of products adds to sustainability gains in terms of packaging.”
Costs of equipment vary
He says the cost of dosing equipment varies considerably depending on the application and features of the system. “Typically the cost of the equipment will pay for itself within six months of installation,” he said. “However, while free-on-loan equipment has been a common approach among chemical suppliers, some companies are ‘unbundling’ free-on-loan equipment so that they can understand the hardware cost, installation cost and service cost as well as the cost of the chemical.”
Dema’s latest chemical dosing product is the Safe Link system which consists of a bottle insert and cap assembly that attaches to the dosing system. Safe Link is designed to improve the interface between chemical packaging and dosing equipment.
Though chemical dosing systems are widely claimed to be more sustainable than glug-glug dosing, the sustainability or otherwise of a dosing system is by no means a clear-cut issue according to Diversey’s sustainability manager Ed Roberts.
“If you look at the typical sustainability model you need to take into account three factors – namely the environmental, the social and the economic aspects of any product or system,” he said. “The benefits of the various different dispensing systems available will vary depending on the customer.”
He claims that sophisticated dilution control systems are generally the best option in terms of the environment because they provide chemical solutions at the right concentrations. “This means they do their job very effectively and with very little wastage,” he said. “They are also better from a social point of view because staff are not exposed to neat chemicals which would represent a health and safety risk.
“However, the downside is that dilution control systems tend to be more expensive than traditional methods since they need plumbing into the mains plus the services of an engineer. And if a dilution control system blows the monthly budget, it won’t make financial sense for a smaller company.”
He says dilution control systems tend to be the most sustainable choice in establishments such as schools, universities, hospitals, drug factories and large offices. “Besides being more accurate, such systems are also generally lower in cost than if you were, say, to buy trigger bottles from the local supermarket,” he said. “Meanwhile, the fact that they are super-concentrated means that there is less packaging and less waste.”
However he said dilution control systems may prove to be less sustainable in lower-use areas. “One bottle of a super-concentrated chemical is equivalent to around 10 five-litre containers of a ready-to-use solution,” said Roberts. “Depending on the product, the shelf life of this super-concentrate may be around two years. In a large establishment such as a hospital this product will be used up relatively quickly but in, say, a high street bank, the amount of chemical used on a daily basis will be much lower and one bottle may last for three or four years. This may result in some of the chemical being thrown away, which will not be sustainable.”
According to Roberts a simpler portion control system can be a good “middle ground”. A portion control system involves a pelican pump that delivers a set volume of chemical where it is required.
“While portion control systems take out the guesswork, there is nothing to stop you from putting in a little extra, however,” he added. “Some systems have a time delay to discourage people from putting in an extra dose, but time delays can be a pain in the neck if you are actively trying to add more chemical. And with a portion control system, people will have access to the neat chemical which is a health and safety issue.”
He says traditional 'glug-glug' methods have the obvious safety and sustainability disadvantages of exposing workers to neat chemicals while providing erratic chemical concentrations. But he adds these are still generally more sustainable than trigger spray bottles. “Trigger-sprays involve a great deal of packaging and add to the transport burden since the products inside the bottles are pre-diluted,” he said.
“However ready-to-use products may be the most sustainable option in certain circumstances. A trigger-spray bottle is safe; involves no manual handling issues and does not allow operatives to over-dilute or under-dilute. So trigger-sprays may be the best option on smaller sites where there is a high turnover of staff who are not well trained.”
According to Roberts dilution control systems are generally the most sustainable option followed by portion control options, then glug-glug dispensing, and then ready-to-use trigger spray bottles.
“But this is by no means cut-and-dried – and in fact as we have seen, in certain situations this order will be reversed,” he said. “Dilution control systems are the ultimate in sustainability because they provide chemicals at the right concentration which means they provide the right level of germ kill and carry out the job effectively and with very little wastage. But due to budget constraints they are not for everyone.”