By W. Brad Carr, President: SonicAire
Two strategies address how to control combustible dust: a managed solution or an engineered solution. Even though the goal is the same, the principles undergirding each approach are vastly different. Let’s examine each approach, and determine its strengths and weaknesses.
Managed= Manual Housekeeping
A managed approach is essentially manual housekeeping. In this scenario, third-party cleaning services or plant employees remove accumulated dust and fiber intermittently. The interval of cleaning depends on the processing and the type of particles - the more dust generated, the more frequent the cleaning required.
The approach looks like this: A person gets up on a ladder (worst case scenario) or on a scissor lift and starts removing the dust from overhead structures and processing equipment. Once the dust settles on the floor it is them removed from the building.
The cost of cleaning this way varies widely. A range of prices has been reported to me, including:
• Larry Baker, president of Fuzion Solution, noted that one company in the paper and pulp industry spends an average $2.40 per square foot on manual cleaning.
• For one woodworking facility, the cost of cleaning was $0.40 per square foot.
• One small mill reported spending $10,000 monthly on manual cleaning.
The cost is there, at whatever level. Now the question is - is that a good solution for the price?
Benefits of a Managed Approach
A managed approach is the status quo solution. Before technological advances were made, manual housekeeping was, in fact, the only solution.
Many people find that ongoing cleaning is an attractive option because there are low upfront costs. You don’t have to invest a lot of money at one time to continue either using cleaning services or using your employees to manage combustible dust levels.
What’s more, manual cleaning for combustible dust can even appear not to cost anything, as it is absorbed in operational budgets. It costs, of course, but that cost is buried, which appeals to some companies’ budgeting process. Continuing in this way just seems like less of a hassle.
Manual cleaning also does not need a strategic plan, which can be viewed as a benefit. If companies do not have a capital investment plan, it can be extremely difficult to allocate the funds needed for an engineered approach. Even if the engineered solutions can show ROI for the installation, some companies can’t secure the initial investment needed. Within this framework, ongoing manual cleaning is appealing.
Weaknesses of a Managed Approach
A managed approach means that personnel or third party businesses clean the overhead structures on a continuing basis. This means that these personnel are at risk when cleaning overhead areas, which is considered a mandatory activity. If you have ever seen anyone on a ladder or scissor lift in those high-ceiling plants, you know exactly what I mean. This seems to be a solution that uses dangerous practices to eliminate a dangerous situation. That’s not a trade-off that makes sense to me.
The second weakness in a managed approach is equally problematic. Given the fact that people are scheduled to clean at certain time intervals, it is axiomatic that there are times when the facility does not comply with safety standards. As I said earlier, there is basically a zero-tolerance approach to fugitive dust buildup. The cyclical nature of manual cleaning allows for too much accumulated dust, preventing the plant from being in compliance with OSHA.
The third weakness is a monetary one. A managed approach requires never-ending costs. You have to keep the cleaning services forever because you are always cleaning up after the fact.
Not only are there ongoing costs that continue for the duration of the life of the plant, but there is also lost production time when the cleaning takes place. You can’t clean safely when the machines are operating. Lost production means lost profits.
Engineered = Automated Housekeeping
The assumption of an engineered approach is that technology can be leveraged to automate cleaning processes and continuously protect against the risks of combustible dust accumulation.
Two types of engineering solutions exist. The first is localized filtration. With this the equipment captures the combustible dust by either vacuuming or suctioning. This approach is often needed, but the reality is that it can’t be used alone. Localized filtrations simply can’t capture every particle of fugitive dust.
The second technology is barrier technology, which prevents fugitive dust from accumulating on overhead structures. With barrier technology, a robotic clean fan automatically establishes and maintains OSHA compliance throughout the plant. With this approach, there is a one-time deep clean of fugitive dust, and once that dust is removed, the barrier technology prevents new dust from ever accumulating again.
Often there is a synergy between the filtration and the barrier technologies for enterprise-wide compliance, since they can be effectively used together in one facility.
Strengths of an Engineered Approach
The value of using technology stems from its operating principle. It’s a simple principle, actually: It’s better to prevent dust from accumulating than clean it up after the fact. An ounce of prevention is worth a pound of cure. Only engineered solutions have a proactive approach to prevent dust from accumulating.
The first is that employees are not put at risk to clean. No longer do people have to climb ladders, mount scaffolds or scissor lifts to reach the fugitive dust in overhead areas. Often in these cases, personnel have to extend their bodies beyond the confines of the scissor lift to make sure all the dust is removed. With an engineered approach, these safety hazards are eliminated.
The second benefit is that a one-time investment means a permanent clean. Professionals can show the ROI of their expenditures, amortizing the costs against the ongoing costs of manual cleaning. The duration of the payoff will depend on the technology chosen. An engineered approach allows for automated, controlled cleaning that doesn’t interfere with production.
Most significant is the benefit that an engineered approach means that plants can now be in continuous compliance. Depending on the sophistication of the specific technology, it also delivers consistently higher levels of clean to meet or exceed those standards. Plants can avoid stiff fines and more importantly, keep their employees safe continually.