Subject: Corrosion Resistance of Ladder Safety System Wire Ropes

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1 Technical Bulletin No. LAD002, Rev. A Subject: Corrosion Resistance of Ladder Safety System Wire Ropes. The corrosion resistance of wire ropes used as the carrier com ponent for ladder safety system s varies widely. Often the specific wire rope construction plays an im portant role in the ability to resist corrosion. The carrier cable is an im portant part of the cable ladder safety system s. The carrier m ust withstand the effects of the environm ent that it is installed in, for extended periods of tim e (often several years). Minim al m aintenance is perform ed on the ladder safety system s once they are installed, m aking the corrosion resistance a critical safety issue for those using the system and relying on it to provide fall protection. Testing conducted on two different construction styles of 3/ 8 inch diam eter galvanized wire rope has shown that significant corrosion resistance differences exist between a 1 x 7 construction and a 7 x 19 construction. Third party testing conducted by Stork / Twin City Testing Corporation has shown that a galvanized 1 x 7 construction will withstand over 5-1/ 2 tim es the duration of salt spray testing before red rust appears when com pared to a galvanized 7 x 19 construction. The 1 x 7 construction has an average coating thickness of approxim ately 7 tim es that of the 7 x 19 construction. Test Results Summary Wire rope construction avg. coating thickness first sign of red rust * 1 x 7 galvanized.0025 inches ** 795 hrs. 7 x 19 galvanized inches ** * 144 hrs. 1 x 7 construction conforms to Wire Rope and Strand ASTM A475. Minimum breaking strength 15,400 lbs. 7 x 19 construction conforms to Federal Specification Wire Rope and Strand RR-W-410. Minimum breaking strength 14,400 lbs. * salt spray tested in accordance with ASTM B117 standard **minimum thickness.0012, maximum thickness.0051 *** minimum thickness. 0003, maximum thickness.0004 I n severely corrosive environm ents the use of stainless steel cable and m ounting brackets is recom m ended for optim um product life and product perform ance. Contact DBI / SALA for specific recommendations.

2 Technical Bulletin No. LAD001, Rev. A Subject: Top Bracket Anchorage Strength for Lad- Saf Systems DBI / SALA recom m ends the following values as the required strength of the top bracket connection/support structure per number of users on the system: 1 person 3,375 pounds 2 persons 4,350 pounds 3 persons 5,325 pounds 4 persons 6,300 pounds These anchorage strengths were established as follows: 1. Dynam ic t est ing on t he syst em using a 100- kg sand bag and body belt gave m axim um arresting forces at 1,300 pounds. 2. Static pretension in the carrier cable is assumed 750 pounds (per installation instructions). 3. A safety factor of 2 was applied to the dynamic Maximum Arresting Force (MAF). Result: 1 person system anchorage strength is (2 x 1,300) = 3,350 pounds. This figure was rounded to 3,375 pounds or 15 KN. For each additional user on the system, a figure of 975 pounds was added, representing the MAF of a hum an body (versus a san bag). An assum ption was m ade that a hum an body would generate only 75% of the forces created by the sandbag. Therefore, a two person system anchorage is 3, = 4,350; three person system is 4, = 5,325; and 4 person system is 5, = 6,300 pounds. DBI / SALA is of the opinion that it is very unlikely on a vertical system that m ore than one user would fall at a tim e. Therefore, we have decided not to add additional safety factors onto the arrest loads of the second, third and fourth person attached to the system. The anchorage strengths given here represent the m inim um recom m ended values for newly installed system s. Environm ental or use factors that could affect the long-term strength of the anchorage connection must be considered during installation and accounted for.

3 Technical Bulletin MISC007 Rev. B Subject: Certification / Inspection Frequency The following information describes the normal servicing, recertification and inspection requirements for the DBI/SALA products. Consult the user instruction manuals for complete details and information. Consult DBI/SALA for requirements relating to equipment used under special circumstances. SELF RETRACTING LIFELINES (SRL), CLIMB ASSIST SYSTEMS *DBI/SALA and ANSI require the product to be inspected at least annually by a Competent Person. Extreme conditions of use may require increasing inspection frequency. (In Canada, CSA requires SRL s to be serviced within two years of mfg. date, thereafter annually) *Before each use, DBI/SALA, OSHA and ANSI require SRL s to be inspected (by the user). *After an impact, the SRL must be removed from service (per DBI/SALA, OSHA and ANSI) and inspected. Servicing may be required. WINCHES *DBI/SALA recommends that Salalift I and II winches be serviced and recertified every year. Extreme working conditions may require increasing the frequency. *On a monthly basis, DBI/SALA recommends that a competent person other than the user formally inspect the winches. *Before each use, DBI/SALA requires winches to be inspected (by the user). *After an impact, the winch must be removed form service and inspected. Servicing may be required. RESCUE POSITIONING DEVICES (RPD S) *DBI/SALA recommends that RPD s be serviced and recertified every year. Extreme working conditions may require increasing the frequency. *On a monthly basis, DBI/SALA recommends that a competent person other than the user formally inspect the RPD. *Before each use, DBI/SALA requires the RPD to be inspected (by the user). RESCUMATIC CONTROLLED DESCENT DEVICE *DBI/SALA recommends that Rescumatics have maintenance check performed every 6 months by the user. *On a monthly basis, DBI/SALA recommends that the Rescumatic be formally inspected by a competent person other that the user. LAD SAF LADDER SAFETY SYSTEM *DBI/SALA requires the Lad Saf system (including sleeve) by inspected at least annually by a competent person. *Before each use, DBI/SALA and OSHA require the system to be inspected (by the user)

4 *After an impact, the entire system (including the sleeve) shall be inspected by a competent person. TRIPODS/DAVIT ARMS /SUPPORT STRUCTURES *DBI/SALA requires at least a monthly inspection by a competent person. *Before each use, DBI/SALA, OSHA and ANSI require an inspection (by the user). *After an impact, remove the product from service and inspect. Servicing may be required. LOAD ARRESTORS *DBI/SALA requires the load arrestors to be serviced and recertified every two years. Extreme working conditions may require increasing the servicing frequency. *Annually, a competent person should inspect the units. *After an impact, the load arrestor must be removed from service and returned to a repair center for service/recertification. HARNESSES/LANYARDS /POSITIONING EQUIPMENT /ROPE GRABS, ANCHORAGE CONNECTORS *DBI/SALA and ANSI require the product to be inspected at least annually by a competent person. *Before each use, DBI/SALA, OSHA and ANSI require an inspection (by the user). *After an impact, the product must be removed from service (per DBI/SALA, OSHA and ANSI). TEMPORARY HAORIZONTAL LIFELINE SYSTEM *DBI/SALA requires the system to be inspected annually by a qualified person. Extreme working conditions may require increasing the service frequency. *Before each use, and after installation, a qualified person shall inspect the system. *After an impact, the system must be removed from service (per DBI/SALA, OSHA and ANSI) or returned to the factory for inspection and/or repair.

5 F a l l P r o t e c t i o n E x p e r t s Technical Bulletin Subject: Product Life Date: February 1998 No. MISC002, Rev. E The current DBI/SALA policy on the life of products is totally dependent on the condition of the item and not the age. A DBI/SALA product can be used as long as the inspection performed does not reveal any damage, wear, or other characteristics that will effect the product s performance. The inspection of the product shall be performed according to details outlined in the user instruction manual on the specific product as well as other applicable information provided by DBI/SALA. The frequency of inspections to determine the usability of the product shall be as follows: 1. Inspect before each use (by user). 2. Monthly (by competent person other than user) (for winches, RPD s, Rescumatics, tripods, davit arms) (recorded). 3. Annually (by competent person other than the user) (recorded). After a fall, the product shall be removed from service and destroyed (or used for educational purposes). After a fall, Self- Retracting Lifelines (SRL s) shall be inspected and serviced (if required, see user instructions) by factory authorized service center. Inspection and servicing frequency may need to be modified based on the amount of use and the conditions within the environment the product is used in. Current OSHA and ANSI regulations indicate the following regarding inspection of equipment: OSHA OSHA *Remove impacted systems and components. *Inspect systems prior to use. *Remove impacted systems and components. *Inspect systems prior to use. ANSI Z *Comply with manufacturer s instructions. *Inspection by user prior to use. *Inspect at least annually by competent person. All equipment found to be unusable shall be tagged as rejected and pulled out of service. Copies of user instructions and other available inspection information can be obtained from DBI/SALA. Activation Date Typically the date of manufacture on a product or the date of purchase is used to help determine when a product is due for inspection. The date of the products first use can also be used as an activation date. The activation date is defined as the time when a product is first put into actual service (initally or after service/repair).

6 F a l l P r o t e c t i o n E x p e r t s If inspection timing is based on the activation date instead of the manufacture date, service date or purchase date, the activation date should be recorded in the user instruction manual in the inspection and maintenance log under the inspection date column (or record/document in some manner). Indicate that the entry is date of first use (or activation date). If the activation date is unknown, the product purchase date, service date, or manufacture date should be used to determine when product is due for inspection. Prior to placing a product into service that product shall be properly stored according to the user instruction manual. Learn more about clothing & work wear we have.