T T M A Recommended Practice RP No. 105-13 April 26, 2013 Truck Trailer Manufacturers Association 8506 Wellington Rd. / Suite 101 Manassas, VA 20109 (703) 549-3010 www.ttmanet.org Title: Cargo Tank Risk Management Committee (CTRMC) Vision 2020 for Common Tank Trailer Ladders, Walkways & Dimensions Previous Editions: Originally issued April 2013 1.0 Preface for this and all TTMA publications: 1.1. No part of this document No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system without written permission from the Truck Trailer Manufacturers Association. 1.2. Recommended Practices and Technical Bulletins are furnished by the TTMA as a guide to general practices in the manufacture, use, and repair of truck trailers. However, the scope of the TTMA's Recommended Practices and Technical Bulletins is not exhaustive of all general practices in the manufacture, use, and repair of truck trailers and there may exist such general practices which do not appear in either the Recommended Practices or Technical Bulletins. 1.3. Recommended Practices and Technical Bulletins represent the state-of-the-art that existed at the time of its preparation. Users of Recommended Practices and Technical Bulletins should familiarize themselves with advancements in practices that have occurred subsequent to the Recommended Practice's or Technical Bulletin's publication date. 1.4. The TTMA has not undertaken any evaluation of all the conceivable ways in which Recommended Practices or Technical Bulletins may be used by manufacturers, users, or repairers of truck trailers nor the consequences of such uses. Everyone who uses Recommended Practices or Technical Bulletins must first satisfy himself or herself that his or her safety, the safety of others, or the safety of the truck trailer and any other equipment will not be jeopardized by their use of information contained within the Recommended Practices or Technical Bulletins. 1.5. The Recommended Practices and Technical Bulletins may contain terms or words with specialized meanings. Definitions for such terms or words may be found in TTMA RP No. 36 - Tank Trailer and Tank Container Nomenclature or TTMA RP No. 66 - Trailer Nomenclature. 1.6. Within the Recommended Practices and Technical Bulletins, "shall" is used wherever conformance with the TTMA publication requires that there be no deviation from the specific recommendation. "Should" is used wherever deviation from the specific recommendation is permissible in complying with the TTMA publication. 1.7. Conformity with TTMA publications by manufacturers, users and repairers of truck trailers is voluntary and any non-conformity with such publications is not indicative of the non-conforming practice being deficient. 1.8. Any inclusion of Recommended Practices or Technical Bulletins within any contract, document or standard is voluntary, and any such inclusion shall not imply any endorsement or approval by the TTMA due to the multitude of ways in which the Recommended Practices or Technical Bulletins may conceivably be used.
RP No. 105-13 2 April 26, 2013 2.0 Purpose and Scope: 2.1. This Recommended Practice is intended to suggest a ladder and walkway configuration for new one compartment tank trailers with a capacity up to 8000 gallons (or, about 70 ID at center most manhole) intended for side access. As practical, these suggestions can be applied to other design types. 2.2. The suggested configuration may be employed by industry stakeholders (especially, carriers) in specifying new equipment commencing about 2020. Advance publication of this Vision 2020 allows such entities to plan for changes in their equipment and processes. Most tank trailers have a useful service life approaching 30 years, and so, the suggestions put forth in this document will require decades for full implementation. 2.3. The suggested configuration is aimed to preclude workers (especially drivers and any other authorized person without access to fall prevention and fall arrest devices) from accessing the top of subject tank trailers. 2.4. The suggested configuration has other salient uses, too. For example, architects and engineers designing loading, unloading and wash facilities can reference the attributes presented to optimize their respective work. 2.5. The design and construction of ladders, walkways, and handholds shall comply with applicable local, state, provincial, and national regulatory requirements. 3.0 Background 3.1. Founded in 2010 the Cargo Tank Risk Management Committee (CTRMC) is a group of cargo tank industry stakeholders that meets regularly to improve safety for workers in the liquid bulk tank industry. During General Meetings of the CTRMC, all attendees are called upon to suggest ways our industry can work together to better protect Workers on the Top of Tanks. At the 2nd General Meeting of the CTRMC a plurality of participants felt our industry should develop a document outlining a Vision for future common tank trailers. 3.2. TTMA RP No. 59 - Tank Trailer Ladders and Walkways provides recommended design considerations for basic tank access. All attributes of the suggested configuration should comply with RP No. 59. 4.0 Suggested Configuration 4.1. Zone 1: Side of Tank 4.1.1. The ladder should be positioned on curbside, near the center manhole. (See Figure 1.) However, at the discretion of the owner of subject tank trailer(s) the ladder may be positioned on roadside, or, both curbside and roadside. (All ensuing text and figures are based on a curbside ladder: These concepts may be adapted for roadside use.)
RP No. 105-13 3 April 26, 2013 4.1.2. The ladder should terminate at a side walkway, near the beltline of the cargo tank (between 2 o clock and 3 o clock position). (See Figure 2.) 4.1.3. The side walkway should be high enough to assure compliance with OAW constraints (e.g., 96, or, 48 from centerline), and allow workers of below-average height to access all fittings and equipment in the manhole area. The side walkway should be at least 48 long and 12 wide (nominally). (See Figure 2.) 4.1.4. The side walkway should have guard rails on the front, ladder-side and rear, approximately 36 tall. The ladder-side guard rail may be collapsible (especially, if the guard rail - when vertical - is taller than the top structure of the tank trailer) to prevent interference with platforms at loading, unloading and wash facilities. The opening on the ladder-side guard rail for ladder access should be offset, if practicable, from the primary anticipated position where workers will stand on the side walkway, and may have a chain for the worker to engage during side walkway presence. (See Figures 1 & 2.) The collapsible guard rail should be operable from ground level by hydraulic, mechanical, or pneumatic means if practicable. A brake interlock assembly may be provided at the location of the collapsible guard rail actuation. 4.1.5. A longitudinal grab rail should be provided atop the inner surface of the side walkway. 4.2. Zone 2: Transition Area 4.2.1. An access ladder should be provided between the side walkway and top walkway, located immediately to the rear of the manhole area to aid workers with fall arrest and/or fall protection devices in transitioning between the two walkway surfaces. If practicable, the access ladder should have a platform-type top step. As an option, another access ladder may be offered between the side walkway and the top walkway, located immediately to the front of the manhole area. To accommodate this second access ladder, the front-most top walkway should be at least 24 wide. (See Figure 4.) 4.2.2. Grab handles should not be provided on the top walkway near the access ladder, as this upper surface is intended to accommodate racks for loading, unloading and washing. 4.2.3. On all jacketed cargo tank motor vehicles reinforcement should be installed under (or above) the jacket surface between the inner edge of the side walkway and the manhole area. 4.3. Zone 3: Top of Tank 4.3.1. The top walkway should be positioned to the front, roadside, and rear of the manhole with minimum widths of 12, 12 and 24, respectively. (See Figure 5.)
RP No. 105-13 4 April 26, 2013 4.3.2. Unless absolutely necessary, no top fittings should be provided outside of the boundaries of the center three sided top walkway. Specifically, cleanout nozzles near the tank ends should not be used, if at all possible. (Spinner technology has been developed to thoroughly clean many tanks from the center manhole area.) Relatedly, no top walkway outside of the boundaries of the center three sided top walkway should be provided. In some cases, top fittings will be required outside of the boundaries of the center three sided top walkway; for instance, top unload assemblies on straight round tanks. In these rare cases, a side walkway should be provided from the ladder area to the remote top fittings. 4.3.3. The top walkway should be positioned as close as practicable to the tank top (not raised more than ½ ). (See Figure 6.) 4.3.4. To keep the top walkway surface clear for loading, unloading and wash racks, no guard rails should be provided to Zone 3. (See Figure 5.)
RP No. 105-13 5 April 26, 2013 Figure 1: Curbside View of Zone 1
RP No. 105-13 6 April 26, 2013 Figure 2: Rear View of zone 1
RP No. 105-13 7 April 26, 2013 Figure 3: Rear View of Zone 2
RP No. 105-13 8 April 26, 2013 Figure 4: Top View of Zone 2
RP No. 105-13 9 April 26, 2013 Figure 5: Top View of Zone 3
RP No. 105-13 10 April 26, 2013 Figure 6: Rear View of Zone 3