How to Avoid Fatal Mistakes When Selecting and Using Conveyors, Part I

Preparation of conveyor system specifications by owners/engineers covering their operational, maintenance and training safety requirements often is inadequate and can result in a conveyor accident. In the absence of any OSHA conveyor safety and training regulations, the responsibility for conveyor safety is fragmented between the owners, engineers, conveyor manufacturers, subcontractors and operators. Too often with this ill-defined relationship, available conveyor safety standards are often misunderstood, ignored or overlooked.

Assume an owner/operator is planning a new facility and modifying an existing operation. His project requires a conveyor system employing both new and used relocated conveyors. He plans to use his own engineering and operating personnel to manage this project. However, the owner's people in turn, as necessary, can hire outside engineering services. They will act as their own general contractor, hiring mechanical and electrical subcontractors. The owner will also purchase all new and inspect existing conveyor equipment for relocation. His staff will supervise installation and start-up and conduct initial training.

Available conveyor safety standards

Conveyor equipment users, when purchasing a single piece of a system, need to know and understand not only their equipment's operation and maintenance needs, but also the applicable related codes, standards and regulations. They should receive specific evidence from their suppliers, engineers or contractors that their work and equipment installations will meet the following safety requirements:

The National Safety Council

All material handling equipment and systems must meet the hierarchy established by the NSC some 50 years ago. Safety literature today is still permeated with basic agreement on the order and preference of these controls as follows:

Principle 1: Hazard elimination. If practical, design the hazard out of the product, workplace, job or facility through engineering means.

Principle 2: Safety guards and enclosures. If you cannot eliminate the hazard entirely, enclose or guard it at its source to protect the user.

Principle 3: Safety warnings and instructions. If you cannot guard the hazard, warn or instruct the users as to the dangers of the product under foreseeable conditions of service.

Principle 4: Protective equipment and administrative controls. As an interim or temporary safety measure only, until higher-order safeguards can be installed, give the user personal protective gear or apply administrative controls.

You should never, however, use guards or safety devices to reduce the risk of injury if the risk could be eliminated through engineering design techniques that are technologically and economically feasible. Before relying upon instructions, warnings and training, you should exhaust all technologically and economically feasible guards and devices to reduce the risk of injury. You will be left with residual hazards that will necessitate the use of warnings, training and instructions to some degree. However, the National Safety Council exhorts you to never rely upon warnings, instructions and training until you have exhausted other methods that are more reliable.

For additional information-on NSC, contact www.nsc.org.

The American National Standards Institute (ANSI)
ANSI is the registrar and clearinghouse for standards in the United States. The American National Standards are not developed by ANSI. ANSI provides the procedures for standards development and reviews all actions taken during development of a standard to assure that all procedures were correctly followed by the Standards Developing Organization (SDO) and that due process was accorded to all interested parties and that consensus was achieved.

1. Standards are voluntary unless your customer insists on or requests compliance or your company has a compliance policy.
2. In most of the world this is not the case. European countries have "directives" that must be followed.
3. Some widely known organizations do not use the ANSI process for their standards development, but are part of a cooperative standards developing organization. One of these organizations is the Automotive Industry Action Group (AIAG).

A selected list of related ANSI Conveyor Safety Standards includes (from American National Standards 1997 Catalog — Revised 10/12/98):

• ANSI C2 - 1993; AEM, MMA, LODEM; National Electrical Safety Code
• ANSI Z244.1 — 1982 (R 1993); Lock Out/Tag Out of Energy Sources, Safety Requirements
• ANSI Z535.1 - 1991; Safety Color Code;
• ANSI Z535.2 - 1991; Environmental and Facility Safety Signs;
• ANSI Z535.3 - 1991; Criteria for Safety Symbols;
• ANSI Z535.4-1991; Product Safety Signs and Labels;
• ANSI Z535.5 - 1991; Accident Prevention Tags;
• ANSI/ASME B20.1 - 1993; Conveyors and Related Equipment, Safety Standards;
• ANSI/ASME B15.1 - 1996; Safety Standards for Mechanical Power Transmission Apparatus.

This listing of standards is not necessarily all inclusive. For additional information on ANSI, contact www.ansi.org.

Next month's column will discuss how to apply conveyor safety standards.

George A. Schultz, vice president of Siebert Engineers Inc., can be contacted at 630-268-0020, ext. 3026, or e-mail [email protected].