Plant Safety Starts Before Building and Never Stops

Requirements include a perimeter safety fence, featuring a bolted mesh screen on the floor, sides, and back of the roll former. Photo courtesy of Samco Machinery.

Many are not eager to talk about safety until something goes wrong. Obviously, by then it’s too late.

The setup, operation, and maintenance of roll forming equipment, for example, requires constant safety awareness for everyone working in the facility.

Samco Machinery, in Toronto, manufactures roll forming equipment for a variety of industries, including transportation, energy, storage, consumer products, and construction. The legal requirements for producing safe equipment in Ontario are strict, stricter than the requirements of many other jurisdictions where the equipment is used. That has meant a focus on safety that begins at the design stage.

It also was a focus when the company moved into its new 164,000-sq.-ft. plant in 2013. Setting up a plant to accommodate product flow is important, but it’s just as important to do it with safety in mind.

“We set up the plant to best suit product flow,” said Gerry Birmingham, vice president of engineering at Samco Machinery. “Then we assessed hazard potential.”

The company takes the same approach when installing a new piece of equipment or production line.

“One challenge with long, complex lines as it relates to safety is generally achieving adequate perimeter security,” said Birmingham. “Long lines often are operated with minimal labor and can be located alongside major walkways and thoroughfares.”

A common practice for guarding equipment with large footprints is to use perimeter fencing, which typically includes safety-interlocked access doors located in strategic areas for setup and service. Once perimeter protection is achieved, however, security and protection inside the fencing are still necessary. For example, special interlocks are required to ensure a person entering the line can be protected in the case of an inadvertent start-up if the main gate is closed.

“Machines can be designed to be highly automated, but they still require some level of human intervention such as adjustments, consumable replenishment, and service. Remote pendants with a dead man’s switch and the use of safety limited speed allow skilled operators to manually operate or manipulate the machine while still maintaining controlled safety.”

When a new production line is installed, these three steps should occur:

Painted lines are a low-tech but highly useful safety system for plant floors. Photo courtesy Samco Machinery.

1. Education.
2. Input.
3. Review.

For new custom equipment, actively educating the operator, gaining input, and reviewing all safety measures before the system is installed will help ensure familiarity. Encouraging operators to ask questions about safety barriers and communicating operator habits could uncover, for example, where shortcomings might be. Defining the sequence of operations (SOO) at the beginning of the process will help determine practical safety systems that don’t hinder the operator’s efficiency.

Roll Forming Safety

Roll forming machines do more at higher speeds than ever before, requiring operators and anyone around the equipment to pay close attention to what’s going on. Integrated roll forming lengths are increasing; some are now more than 150 feet long. These lines contain machines for stamping, punching, pre-punching, packaging, bundling, as well as other material handling operations.

“Even though these lines are growing, they may require only one or two operators,” Birmingham said. “Ultimately, they’re responsible for knowing what’s going on all the way down the line. Safety is very much a part of the planning process when installing any machine or line.”

Essentially, all moving parts in a line represent a hazard. For example, rotating rolls can be pinch hazards, and loose clothing can get caught in gears, rotating shafts, and chain drives. In addition, the edges of moving material can present a hazard.

“During production, and especially at high speeds, material jam-ups can occur. Antibuckling sensors can act as watchdogs to initiate a line shutdown in these situations,” said Birmingham.

In press systems, mesh guarding may protect a worker from a moving hazard but be inadequate for a tool failure. In these cases solid guarding might be necessary.

“Essentially, any moving part can represent some level of hazard, so guarding wherever practical should be considered,” he added.

Newer technology, such as light curtains and area scanners, can also play a role in safety systems.

Light curtains are best used in areas where regular access is needed, such as, in front of a roll former where the tooling is regularly removed and overhead cranes or forklifts are present.

“While a light curtain can be an effective barrier for access, it cannot prevent the breach of a broken tool or product,” said Birmingham.

Area scanners can solve complex security challenges.

“This is a well-proven technology with escalating and programmable restriction zones,” said Birmingham. “A zone scanner can be set to allow an operator to enter a loading zone when the operating conditions are satisfied. This occurs during removal and restocking of supply pallets in a dual zone system.”

Overall Plant Safety

Other areas of operation besides a roll forming line also need to be taken into consideration. For instance, in shipping bays, guardrails can be installed to keep pedestrians safe, and lines can be painted on the floor to indicate safe walkway areas and restricted areas.

“Those [types of] markings are great for employees and are helpful to plant visitors as well,” said Birmingham. “You’ll have customers or other visitors in the plant who are often distracted by their surroundings during a walking tour, not paying close attention to what’s in front of them. You want to keep these walkways away from potentially dangerous areas like transition areas, pits, and rail tracks.”

Fire extinguishers and eyewash and first-aid stations should not be afterthoughts during the design and layout process. These areas need to be designed to be highly visible and accessible in work areas.

“Believe it or not, lighting plays a part in safety,” said Birmingham. “In our new plant we’ve upgraded to high-efficiency lighting so there is plenty of light in work areas and no dark spots in areas where someone is working. You should also make sure there are clear paths for evacuation in the occurrence of a catastrophic event. You hope it never happens, but you have to be prepared for anything.”

The main aisles pedestrians and forklifts share need to be wide enough so pedestrians can safely pass by the lifts.

“Floor space is very expensive when building a plant, so it must also be used efficiently, with safety in mind,” Birmingham said.

Adequate staging areas for material waiting to be transferred to another process within the plant also need to be preplanned. While these areas are not always used to capacity, they are important because the keep material out of the way.

Employee Safety

The intent of a safety plan is to make sure a safety system is in place for all common operating scenarios. For example, where there is a hose that can burst, guarding of some kind may be necessary to protect anyone who may be in the vicinity. If product at any stage of the line becomes jammed, what happens to it? Does it drop to the ground or shoot up to the ceiling? Provisions must be put into place to maximize safety.

Training should go together with all new machines to ensure proper and safe operation. It’s the best way to guarantee manufacturers get a machine that increases efficiency safely.

“For the machine operators, training is an essential part of safe equipment operation,” said Birmingham. “An effective health and safety program for operators ensures regular safety talks and safe practice enforcement. As a machine builder, we are often asked for recommended safety solutions. Each company has different views of safety and practices. In our experience, for example, a defective interlock switch or guard should be treated the same as a defective drive motor.”

When a safety system goes down, it should be considered broken and replaced rather than using a temporary bypass.

Safety should never be an afterthought.