Machine safety compliance: start with design
An important first step when considering safety as part of machine design is understanding the scope of what the machine is being designed to deliver. Safety in design is critical to the end products as well as to the machine’s profitability, whether the equipment is designed to deliver compressed air; cuts or forms metal parts; assembles parts; or makes widgets. Safety in design includes an understanding of the machine throughput information (how many parts per hour). Evaluate the complexity or simplicity of the machine’s loading and unloading process (manual or automatic), and in-feed and out-feed requirements (how do raw materials get into the machine and finished parts get out of the machine) during the design phase.
Floor space requirements can best be determined during the design stage as well. Consider the machine footprint, such as how much space is needed for the machine, the operator, material handling machine access (such as forklift, conveyors, etc.), production component marshalling, material storage, access for removing end product components, and packaging materials; and how waste will be handled. What services will be needed to power and operate the machine, such as air, electricity, water, vacuum, etc.? Consider what is needed as well as the source for these services.
Include ergonomics during the design phase. Adjustable equipment should be able to be operated by any person. Adjustability must be designed into the operator’s panel and input stations allowing for risk-free, user friendly, and efficient operation of the equipment.
One guide for the ergonomics engineering solutions is the book, “Kodak’s Ergonomic Design for People at Work.” There are currently no OSHA or European ISO 18001 standards for ergonomic design, but that doesn’t mean citations cannot be issued by OSHA in the U.S. OSHA will issue citations to companies for poor design via its General Duty Clause, which states the employer must provide a workplace free from recognized hazards. Industrial illnesses caused by repetitive motion, such as carpal tunnel syndrome, are considered recognized hazards by OSHA.
Along with ergonomics, the Americans with Disabilities Act (ADA) must be considered during design. The U.S. Department of Justice’s revised regulations for Titles II and III of the ADA Act of 1990 were published in the Federal Register on Sept. 15, 2010. The Department has assembled an official online version of the 2010 ADA Standards for Accessible Design (2010 Standards) to compile the information in one easy-to-access location. It provides the scoping and technical requirements for new construction and alterations resulting from the adoption of revised 2010 Standards in the final rules for Title II (28 CFR part 35) and Title III (28 CFR part 36).
The Justice department has also compiled guidance on the 2010 standards from the revised regulations for Titles II and III. This explanatory information from the regulations addresses the scoping and technical provisions of the 2010 standards. The new requirements can be found at ADA.gov or within the U.S. Department of Justice Civil Rights Division.
Beyond safe machine design, a health, safety and environmental (HSE) plan is needed. Front-end loading, a thorough planning proactive approach to machine design, can help bring to mind everything that needs to be considered. The HSE plan, if thorough, will raise a high percentage of the safety concerns so these issues can be resolved in the earliest phases. Use the HSE plan to facilitate the construction of the operating facility and help answer questions raised during this phase of engineering as well. HSE plans are not required by OSHA’s 29 CFR 1910 General Industry, 29 CFR 1926 for Construction, nor by ISO 180001. They only require that all hazards be recognized and addressed prior to starting construction and starting equipment.
OSHA provides the requirements for exit routes, emergency action plans (emergency access, egress, exits, and emergency response signage, etc.) and fire prevention plans in Subpart E of 29 CFR 1910.33 through 1910.39. Since safety standards differ by country, designers should consider the country in which the machine will be located and operated. If the machine has running or moving parts that would require guarding, related regulations are spelled out in 29 CFR 1910.211 through 29 CFR 1910.219 Subpart O. All operating hazards must be identified during design so that interlocking guards can be included to protect those who will operate the machine and require access for maintenance activities. Electronic stops (e-stops) also need to be designed and labeled so equipment can be immediately shut down if an out-of-control situation were to occur. OSHA provides direction for lockout/tagout (LOTO) and hazardous energy control in 29 CFR 1910.147 Subpart J. OSHA requires that new equipment be designed such that personal protective equipment (PPE) would not be required for machine operators to be safe in Subpart I, 29 CFR 1910.132. The standard directs that new equipment shall design out any hazards that could be serious enough to require PPE if at all feasible. It should be noted that feasibility is not necessarily a cost or a convenience issue. Safety standards related to electrical safety are found in Subpart S at 29 CFR 1910.301 through 399.
These standards are examples of OSHA performance standards, which describe what needs to be done to achieve compliance. ISO 18001 provide overarching high-level guidance and does not provide direction on how to perform these types of work.
OSHA isn’t the only standard enforced. Other standard writing organizations documents are referred to and/or incorporated into OSHA regulations. Many of the American National Standards Institute (ANSI) standards, as well as those from the National Fire Protection Association (NFPA), are incorporated by reference into the OSHA standards, which make them enforceable by OSHA. These are only two of many incorporated standards that must be considered during the design phase for machine compliance.
A key component to the functionality of the machine is the design of and usability of the operator’s station and the accessibility of the machine components to maintenance personnel who will need to service and repair the machine.
Many machines are designed with production rates in mind, and this can lead to re-design once operations and maintenance begin. Re-design because of complications with operators or other humans can be very costly, resulting in injury, quality issues, low production rates, and machine shutdown time. The same issues arise when a machine is designed without considerations for how the machine will need to be serviced, repaired, and maintained. Some designers do not have a good understanding of what it takes for a mechanic to gain access to the motors, gearboxes, chains, sprockets, and the like, so servicing can be completed quickly and, in many cases, without shutting down the equipment.
The inability for maintenance staff to easily and quickly access equipment parts that need service and or repair also can lead to extended downtime. Fixing design errors makes retrofit or re-design extensive and expensive. Failure to re-design or even just living with these problem areas (the issues not considered in the original design process) can lead to worker morale issues, dissatisfied customers, and a loss in future business.
Cost of noncompliance
Noncompliance may be disregarded as the cost of doing business. These costs can be broken down into two groups, direct and indirect costs. Direct costs are those easily identified, such as cost of wasted materials, hours spent in making inferior nonsaleable products, and wasted raw materials. Cost of injuries, insurance, and worker’s compensation expenses are among examples of direct costs.
Indirect costs are more subtle and sometimes not as easy to identify. The cost of extra administrative duties, additional paperwork, incident reports and recordkeeping, extra meetings to discuss the proper resolutions to a given problem, loss of clients because of poor quality products, and negative media coverage are all consequences not easily quantified. Indirect costs can lead to lower worker morale, employee turnover, and injuries. Poor design can result in bringing in more employees or temporary employees to work on equipment not functioning properly or even doing the production work by hand because of a machine failure.
Safety compliance is the competitive edge
Professional engineers strive to design equipment and machinery so that it is “done right, the first time, without incident.” Safety compliance designed and built into machinery is a proactive approach that will give companies a competitive edge for anyone who interfaces with this equipment. Engineering “done right” builds quality into the equipment.
“Done right, the first time” gives a company the quality edge, plus provides a better opportunity for achieving the desired schedule. When combining “done right, the first time, without incident,” quality is achieved, schedule is maintained, and losses and waste are reduced. All these factors lead to machine safety compliance and a competitive edge.
Companies on the leading edge include safety engineering in the design phase of project work to provide a different set of eyes to look for and identify gaps that may lead to safety problems when the machine begins production. Most safety engineers would be looking for all of the issues outlined here and other safety concerns that may present themselves during the HSE planning process.
– Al Manzer is Optimation corporate safety engineer. Edited by Mark T. Hoske, content manager, CFE Media, Control Engineering and Plant Engineering, firstname.lastname@example.org.
At www.controleng.com, search Optimation for other advice.
- Machine safety compliance starts with design.
- Use applicable standards (see table).
- If you think compliance is expensive, add up noncompliance.
Machine safety compliance designed into machines and processes results in higher quality, less downtime and waste, and fewer losses.