FAQs


Product: Light Curtain

What is the difference between “Muting” and “Blanking” of a safety light curtain?

Muting is characterized as the automatic, temporary suspension of a safety function. Blanking allow portions of a light curtains sensing field to be disabled to accommodate objects typically associated with the process.

How do I calculate “Safety Distance” for a light curtain?

The minimum safety distance is dependent on the time required to process the Stop command and how far the operator can penetrate the detection zone before detection. Hazards must come to a safe state prior to an operator reaching the hazard. For the safety distance calculation, you can use the following standards in the US and Canada (ANSI B11.19, ANSI RIA R15.06 and CAN/CSA Z434-03).

Product: Rack Column Protection

Can I install a protective device on a damaged upright column?

No. Only protect undamaged components. Most upright column protective devices will hide the damage and mislead inspectors and users in believing the rack is safe.

Do we need to protect racks at every end-of-aisle?

Not necessarily. End of aisles have a high damage potential. We suggest protecting the rack uprights located in high traffic areas such as at the end-of-aisles and tunnels.

What should I do about repetitive damage occurring on the same upright columns?

The damaged components must be isolated, stabilized, and then repaired or replaced. Perform a root cause analysis to evaluate the cause of the reoccurring damage. Implement preventative procedures to address the results of the analysis. Guarding products are available that may help mitigate future damage.

Product: Building Column Protection

Is it necessary to protect exposed building columns located in traffic areas?

Yes. You should protect building columns that are exposed to potential forklift impacts. In addition to obvious safety concerns like building integrity, building column repair or replacement is a costly undertaking.

How can I protect the back frame (or X braces) of my drive-in from being damaged by pallets?

One available solution is to use pallet stoppers anchored in the concrete floor and use rail stoppers on each level.

Product: Mezzanines

What is a “Pallet Access Gate”?

Pallet Access Gates secure the ledges of elevated work platforms and pick modules, creating a fall-protection barrier where openings exist in guardrail to allow the loading and unloading of palletized material. A pallet access gate should be designed to meet OSHA, IBC and ANSI standards configured so a barrier is always in place to secure the ledge while allowing access to the pallet loads. One method to accomplish this requirement is dual counterbalanced gates.

Product: Perimeter Guarding / Fixed Distance Guarding

What is “Perimeter Guarding”?

Perimeter guarding (or Fixed Distance Guarding) is used to prevent or detect an individual entering a hazardous area through permanent barriers that cannot be removed without use of a tool or electro-optical presence-sensing safeguarding devices.

What is maximum sweep space (gap between the adjacent walking surface and bottom of guard) allowed for perimeter guarding?

The maximum ground floor sweep space must be small enough to prevent an individual from accessing the hazard by reaching or crawling below the barrier guard. Perimeter barrier guards must be designed so that the bottom of the barrier is no more than 7.8 inches (200 mm ) above the adjacent walking surface per ISO 10218-2:2011. Canadian regulations also specify a maximum opening of 150 mm (6 inches) per CSA Z434-03.

How tall should perimeter guarding be?

ISO 10218:2011 requires the top of the barrier must be no less than 1,400 mm (55 inches) above the adjacent walking surface according to ISO 10218-2:2011. The Canadian standard (CSA Z434-03) requires a minimum height of 1,800 mm (71 inches). Use the following standards to assist in determining the adequate height of perimeter guards in relation to the hazard height: Please note these are the minimum requirements and a risk assessment should be completed to calculate the safe height of the barrier.

  • ANSI B11.19-2010 – Performance Criteria for Safeguarding
  • CSA Z432-04 – Safeguarding of Machinery – Occupational Health and Safety
  • ISO 13857:2008 – Safety of Machinery – Safety distances to prevent hazard zones being reached by upper and lower limbs.

Can I exceed the perimeter guarding requirements defined by ISO 10218-2:2011 or CSA Z434-03 by installing taller than recommended and/or lower than recommended guarding?

Yes, it is permissible to exceed these requirements.

How close can perimeter guarding be to moving equipment?

When determining the safe mounting distance for a perimeter guarding, first consider the largest opening in the guarding material. The current OSHA standard for safe distance as a function of opening size is set forth in Table O-10 of OSHA 29 CFR 1910.217 – Mechanical Power Presses. The following standards are also very helpful in determining a safe working distance:

  • ANSI B11.19-2010 – Performance Criteria for Safeguarding
  • CSA Z432-04 – Safeguarding of Machinery – Occupational Health and Safety.
  • ISO 13857:2008 – Safety of Machinery – Safety distances to prevent hazard zones being reached by upper and lower limbs.

What are Requirements for guarding a vertical lift?

VRCs can move materials from one level to the next. VRCs are not considered elevators and are exempt from national elevator codes. They have their own national codes (ASME B20.1) listing requirements for guarding. (http://www.mhi.org/free/4572).

What is the purpose of a “Safety Interlock”?

A safety interlock can be mechanical, electrical or other type of device, the purpose of which is to prevent the operation of hazardous machine functions under specified conditions.

Product: Guard Rail

Where should Guard Rails be installed in a facility?

Where possible, guard rails may be used to create dedicated pedestrian aisle ways, which physically segregate people from industrial traffic and, therefore, increase safety on the work floor. Guard rails may be used in front of equipment or building walls. By controlling and containing vehicle traffic, guard rails prevent damage to infrastructure from inadvertent contact with vehicle traffic.

Since guard rail systems have different thicknesses, dimensions, and deflection upon impact, how close can the guard rail be installed to what I am protecting?

Heavy-duty systems should be able to provide a safety zone upon impact of up to 10 inches from the center of the guard rail. When in doubt, ask the manufacturer to provide the deflection rating for their product to be sure it meets your needs.

What are the OSHA guidelines for use of Guard Rail in a facility?

There is currently no guideline for use of Guard Rail.

Product: Rack Safety

What is Pallet Rack Guarding or Pallet Rack Backing?

Pallet Rack Guarding and/or Pallet Rack Backing refers to a type of containment guard mounted on, or adjacent to, pallet rack for the purpose of controlling spillage of stored materials. The guards may be constructed of several different types of materials from netting to wire mesh.

Is Rack Guarding (or Rack Backing) rated, and if so, are there standards for how much force it should resist?

Rack Guarding is intended to arrest or prevent product or materials from falling, or help prevent items from moving beyond a set space. It is not intended to stop mobile equipment. Currently there are no standards for the amount of horizontal force Rack Guarding should withstand, nor is there standard testing methodology.

Product: Fall Protection

At what height do I need fall protection for elevated work platforms?

OSHA regulation 1910.23 for Guarding Floor and Wall Openings and Holes requires that on platforms four feet (4’) or higher a barrier be in place to guard every open sided floor and that the barrier be in place when the opening is not in use for handling materials.

A toe board (or equivalent) should be provided when there is exposure below to falling materials. A standard railing consists of a top rail 42” off of the deck and an intermediate rail and must withstand a 200 pound force applied in any direction except upward.

ANSI MH 28.3-2009 in section 6.4.3 requires a barrier to be in place on elevated work surfaces of three feet (3’) or higher to secure pallet drop areas at all times - even while the area is in use for handling materials.

Only a dual-gate system ensures compliance with ANSI and OSHA because a dual-gate system will always have a barrier in place. A dual-gate system does not depend on an operator to remember and make an effort to close the barrier.

How should picking positions in a rack supported pick module be guarded?

Elevated picking areas 36” or taller should be secured so there is always a barrier separating the worker from the ledge. In order to create this level of safety while allowing the lift truck to load pallets into the system, a dual-gate system should be installed. A dual-gate system secures the pallet drop areas with a gate at the ledge and a second gate behind the pallet. These two gates are counterbalanced and interconnected so one gate is always closed, separating the operator from the ledge while creating a safe environment for the employee picking items from the pallet. These systems are typically manually operated but can be powered for remote access by the lift truck operator. They area available in either free-standing or rack-supported construction. The rack-supported design attaches directly to the rack components to maximize space in the bay and to eliminate the need of securing the gate structure to the decking.

What guarding should be used for empty pallet/empty tote return bays in pick modules?

Many fall-related incidents occur where the empty pallets or empty totes are stacked, waiting to be removed by the lift truck. These areas should be secured with a dual-gate system so a barrier is always there to provide fall protection. They are available in either a rack-supported or free-standing design. The rack-supported design attaches directly to the rack components to maximize space in the bay and to eliminate the need of securing the gate structure to the decking.

How are the ledges of pallet flow lanes best guarded?

The ideal solution is a dual-gate safety system that maintains a safe environment for pickers at all times. This design uses a gate at the ledge and a second gate at the end of the lane where the picker is standing. The gates are interconnected and counterbalanced so when one gate is open, the opposite gate is closed. Operationally, the ledge gate is open when the lift truck loads load pallets into the lanes, which means the rear-side gate is closed, preventing employees from accessing the lane and keeping them a safe distance from the ledge. Pickers then can manually raise the rear gate, which closes the ledge gate, providing fall protection while they pick from the pallets, as well as preventing the lift truck from loading more pallets while they are in that area.

Do pallet flow lanes need guarding if they are decked over?

Yes. The decking moves the ledge from the picking position out to the end of the lane, but this end also needs to be guarded because there is now an egress into the lane. In cluster-picking applications, this egress is designed into the design so the pickers can pick from several pallets off of two lanes, but most times the operation doesn’t ask for employees to enter the lanes. The decking allows egress into the lane so the edge of the lane must be guarded.