6.7 External Peer Review and Responses 6.7 External Peer Review and Responses An external peer review

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  • Ecointesys – Life Cycle Systems [51]

    6.7 External Peer Review and Responses

    An external peer review has been conducted to ensure compliance with the requirements of the ISO 14040 and

    14044 standards for making a comparative environmental claim. The external peer review panel was

    comprised of Dr. Gontran Bage, Ms. Marylène Dussault and Dr. Anthony Halog. Their comments following an

    initial and final review are appended to this report. Comments from the original review panel‘s response are

    shown below in plain type. Responses to the comments are shown in italic type. The original correspondence

    from the panel is attached. All points in the panel‘s final statement have been modified as suggested.

    Life Cycle Assessment Methodology

    Section 2.1

    1. In accordance with the philosophy of LCA approach, it should be explicitly stated at the beginning of the report that

    the environmental impacts associated with each product system are potential and not real.

    Statement added in section 2.1

    Section 2.2

    2. In section 2.2, it is stated that the functional unit represents ―a typical service rate for a single installation of any of

    the systems over a 10-year lifetime‖. Hence, all product systems studied use one unit over the studied time frame.

    No justifications for the product lifetimes are provided. This should be clearly stated in the report, especially since

    many assumptions are taken from the Environmental Resources Management (2001) and this report considered a

    5- year lifetime for both the paper dispenser and hand dryer system, which is not consistent with this present LCA


    The 10 year lifetime was used based on the input of Excel Dryer inc., whose input was that each system in

    question is likely to last at least that amount of time. No known source of information is available on the true

    lifetime of these systems. Review of the initial results of the study did not implicate this as a variable to which

    the directional conclusion of the study might be sensitive within the range of reasonable inputs, as for each

    system the initial production impacts are a minor component and of a similar scale. A note on the selection of

    10 years has been included in section 2.2

    Section 2.3

    3. What is the justification in the choice of product system alternatives? Are there no other product systems in the

    market, besides those mentioned in this LCA document? Were the considered product system alternatives in this

    LCA study selected in random or they based on actual market share of various hand drying systems?

    The alternatives considered are representative of the great majority of the market share. While other systems

    exist, their market share is extremely small and it is not felt that there is any interest on the part of the client or

    their customers in seeing such a comparison. Other systems include single-use cloth towels and multi-use

    cloth rolls.

    4. The product system for the conventional dryer is said to be ―typical of the leading options in this market over the

    past several decades‖. However, the conventional dryer studied specifications include wattage of 2300 W. This

    seems to be at the high end of the wattage range of the available hand dryer models in the market. A quick search

    in the available models from different companies showed variation in wattage from 1300 W to 2400 W. Product‘s

    wattage greatly influences the electricity requirements of the use phase for which this study has shown to have the

    most important potential environmental impact for the dryers‘ life cycle. Hence, the panel thinks that the wattage for

    the conventional hand dryer should be justified and represent the typical product type in the market. On the other

    hand, Excel Inc. could specify that the XLERATOR is comparable with the conventional hand dryer that they

    manufacture with 2300 W wattage and state the specific model studied in the report.

    Electric dryers on the market tend to cluster in two categories: those represented by the high efficiency

    (XLERATOR) and the conventional dryers. All dryers in the conventional category use primarily evaporation and

    a lower air speed. These systems are all designed around a motor type that will draw somewhere in the range

    of 2300 to 2500 watts. The higher efficiency dryers achieve dryness primarily by blowing water off the hands

    and then evaporating what remains. These fans require a higher air speed achieved by a higher efficiency

    motor. All dryers of this type will have a wattage of around 1100 to 1500

  • Ecointesys – Life Cycle Systems [52]

    watts. The 1300 W dryers you have found are therefore more similar to the XLERATOR than to the standard


    5. Several comments should be added to the elements in Table 1.

    5.1. For the product characteristic considered, wattage use is stated in motor power (e.g. ―1500 Watt motor‖). Usually,

    motor power is lower than the product wattage. Is the considered wattage adequate?

    The wattage given is intended to refer to the electrical draw of the dryer unit rather than as a power rating of the

    motor. The wording in Table 1 has been clarified.

    5.2. It should be clearly stated that the energy needed for each electric dryer includes both the electricity during the use

    (maximum power) and the electricity during the shutdown (fraction of the power) phases.

    This has been added to Table 1

    5.3. The energy given for the XLERATOR (1165 kWh) is for the use phase of 10 seconds (plus the shutdown) and not a

    12 seconds run time as stated.

    The proper value has been added. The other value was from a prior draft. The update was needed for the table

    only and there is no change to the results.

    5.4. The amount of paper required to fulfill the functional unit should be revised and recalculated. 260 000 usages of 2

    towels with 0.073 m2 per towel gives a total of 37,960m2 of paper.

    Similar situation as the above item. The update has been made to the table; no update needed to results.

    5.5. It should be explained in the report why the average distance for all components for the supply chain of the

    XLERATOR is smaller than for other compared product systems. Without any explanation, this could be seen as a

    bias in favor of the XLERATOR system.

    Excel Dryer sources over 90% of their components by weight from within the US, which is uncommon for their

    industry. However, since no accurate data is available regarding the supply chain or distribution systems of the

    other components, all the systems have been adjusted to have the same inbound and outbound shipping

    distances (750 km by both ship and truck for all components). This prevents any advantage being given to the

    XLERATOR due to the uncertainty and variability in the transportation logistics of the other systems.

    5.6. The modeling of the transportation phase of the conventional dryer and the paper towel options is not clear. In table

    1, transport distance stated is ―750 km‖ average for all components while in section 6.3 inbound shipping distances

    is stated as ―750 km by truck, 750 km by ship‖. Are these distances additional or have portions of the transport

    distance been modeled by truck and others by ship? The panel thinks this needs clarification.

    As noted in the above response, these values have been changed and the descriptions have also been

    updated and clarified based on the revised values. The transport includes 750 km by truck and 750 km by ship

    for all components.

    5.7. Run time for both types of dryer systems is a critical parameter in this study and should be clearly and thoroughly

    justified. For example, elements such as the way these run times have been evaluated, the data quality, accuracy

    and uncertainty should be discussed. It is noted that run time for dryer similar to the conventional hand dryer system

    in the Environmental Resources Management (2001) report has been set to 30 seconds despite the fact the

    manufacturer reported 20 seconds. These authors felt that the run time reported by the manufacturer (20 seconds)

    wasn‘t reliable enough and then chose a conservative hypothesis of 30 seconds when comparing with paper towel.

    In this study, such run time estimate (35 seconds) can favor the product for which the commissioner of the study

    wants to demonstrate the environmental superiority of this dryer over any other product systems considered.

    Extensive research conducted by Excel Dryer, Inc. (by Aisenberg and Freedman) during the design of the

    XLERATOR has shown a range of 10 to 15 seconds for the XLERATOR and 30 to 45 seconds for conventional

    air dryers to achieve equivalent and satisfactory dryness. A report summarizing this research is being provided

    to the peer review committee and is available to others by request to Excel Dryer, inc. A reference to this report

    has been added to the report where appropriate. To be inclusive of the 20 second number given in the ERM

    2001 report, the ―low intensity user‖ scenario has been changed from 25 seconds to 20 seconds, although the

    information from the Aisenberg and Freedman report suggest this is well below the range that will achieve

    adequate drynes