Part 3: Snowboard Wax

In this three-part series I covered snowboard base dynamics to help prepare your equipment and get a better understanding of how conditions impact riding. In Part One I covered the physics effecting movement on the snow. In Part Two, I covered the snowboard base material, and base structure theory. In this last installment I will cover the role of wax, wax structure, and health and risks.

Part 3: Snowboard Wax

Snowboard Wax

In a simple explanation wax is used between the base and the snow to reduce friction. There are a few different types of friction we try to overcome using wax. When wax is applied to a snowboard base, it is melted and then ironed into a thin layer. When cool, the excess is scraped away and then even more excess is removed from the base with a stiff brush. One can also ‘crayon’ the wax on to the base and use a cork to  A physical energy that can push or pull on something. Your weight is the force that you push on the earth with, when there are no other accelerations." class="glossaryLink " target="_blank">force the wax in to the pores.

Friction

There are many types of frictional forces in physics, but we deal primarily with two forces of friction [kinetic and static] in snowboarding; dry, wet, and sometimes electrostatic.

  • Dry friction occurs when the melt-water lubrication is absent or insufficient; this is the case at low temperatures or at low sliding speeds when dry snow granules come in contact with the ski base. Essentially you want wax slightly harder than the snow particles. If a wax is too soft the snow crystal will penetrate into the wax causing a grippy base. However, if the wax is too hard the is a multiplicative factor in some term." class="glossaryLink " target="_blank">coefficient of friction will be higher and the base will be less slippery.[1]Kuzmin, Leonid (2010). Interfacial kinetic ski friction (Doctoral). Mid Sweden University, Retrieved December 2, 2014 from http://miun.diva-portal.org/smash/get/diva2:319312/FULLTEXT01
  • Wet friction occurs with a high moisture content snow creating suction between base and snow. A fluorocarbon additive is sometimes used to reduce the wet friction. However, it’s important to not use too much fluorocarbon as it will increase the dry friction and reduce glide.
  • Electrostatic friction is static electricity generated when a base runs on snow creating an electrostatic attraction between the board and snow. Graphite is commonly introduced into the base to reduce static electric.
Purl wax
Purl wax

The basics of wax

I have tried numerous hydrocarbon is an organic compound consisting entirely of hydrogen and carbon." class="glossaryLink " target="_blank">hydrocarbon waxes out there, most all of them are similar. When I worked as a ski tech at Keystone Resort many years ago, the wax formula was very similar to what it is now. Basically companies were trying to manipulate a paraffin wax hardness to different temperatures and conditions of the snow. Back then, the color of the wax was an easy way to tell the wax hardness. For warmer conditions a wax in the red spectrum was used, and for colder conditions a blue spectrum color was used. This evolved in to virtually every color in between, and the black art of mixing waxes to achieve specific hardnesses for specific conditions was born. Colored waxes today are nothing more than a marketing gimmick to tint the wax, similar to adding a crayon to the mix to offer some mystique.[2]Masia, Seth. (2012) History of Ski Wax, Retrieved November 29, 2014, from http://skiinghistory.org/history/grip-and-glide-short-history-ski-wax[3]Kuzmin, Leonid (2006). Investigation of the most essential factors influencing ski glide (Licentiate). Luleå University of Technology

There are basically three types of wax; hydrocarbon waxes, fluorinated hydrocarbon waxes, and fluorocarbon overlays.

  • Hydrocarbon waxes are simple paraffin waxes that have varying amounts of oils and synthetic hardeners in them which determine their hardness and what conditions they might be best suited for.
  • Fluorocarbon waxes do not mix with hydrocarbon waxes. Fluorinated hydrocarbons are a hybrid link between them. A fluorinated hydrocarbon is not simply a block of wax containing a mix of a hydrocarbon and a fluorocarbon wax. The combination is actually at the molecular level.[4]Moldestad, D. A., (1999). Some aspects of ski base sliding and ski base structure, PhD thesis, Norwegian University of Science and Technology.[5]Lehtovaara, A., (1989). (or dynamic) – Occurs when two objects are moving relative to each other and rub together." class="glossaryLink " target="_blank">Kinetic friction between ski and snow, PhD thesis, Tampere University of Technology, Finnland.
  • Fluorocarbon overlays are the most expensive sprays, powders, and blocks. These products do not penetrate the base the way hydrocarbon waxes do and are also more challenging to work with.

Hydrocarbon wax

This is the most basic of waxes. These waxes are primarily made up of three types of hydrocarbons: paraffin, microcrystalline, and synthetic waxes that are combined together in various proportions. Paraffins are soft, candle-like waxes, that have low coefficients of friction allowing the board to glide easily over the snow crystals. Microcrystalline waxes are a branched type of hydrocarbon that are more durable than paraffins and do not wear off as fast. Synthetic waxes are slightly branched hydrocarbons that also make the wax stronger. All waxes use a hydrocarbon base to which various additives are incorporated.[6]Coupe, Richard (2008). An Investigation Comparing the Efficacy of Different Lubricants for Skis on Artificial Snow. The ACES Journal of Undergraduate Research, Sheffield Hallam University.[7]Giesbrecht, Jan Lukas (2010). Polymers on snow: Towards skiing faster (Doctoral). Swiss Federal Institute of Technology

Fluorocarbon wax

It was Terry Hertel that developed and introduced a fluorocarbon wax to the ski industry in the late 1980’s. Hertel owns several patents on glide wax,[8]Hertel, Terry (1992) US Patent US 5114482A  http://www.google.com/patents/US5114482 although it’s not as much of a secret as one would imagine, a spectroscopy and CHN analysis does reveal a breakdown of the contents. Elemental analysis can be qualitative (determining what elements are present), and it can be quantitative (determining how much of each are present). While toxicity levels are low, many of the waxes on the market today contain them. Fluorine is the most electronegative of all the elements. When substituted for one or more hydrogen atoms in a hydrocarbon wax, the new fluorocarbon wax becomes incredibly hydrophobic, which is why it is great as a snowboard wax. Usually some degree of fluorocarbon or surfactant is in the common wax ingredient. Hence began the ‘all-temperature’ waxes, basically a wax that would perform from 5°F to roughly 50°F. Although, that is subjective to actual snow snow-structure, age of the snow, and water content in the snow. Temperature, while a main factor, is not the only factor.[9]Pihkala, P.; Spring, E., (1986). Determination of the contact area between ski and snow using a simple thermal conductivity meter, Report Series in Geophysics, University of Helsinki: Helsinki.

Which wax to use

A variety of hydrocarbon snowboard waxes
A variety of hydrocarbon snowboard waxes

Sometimes you have to choose your own toppings on your pizza. I try to use a natural wax when the conditions permit. For the most part, I use Purl wax, depending on the conditions. I also use Hertel Hotsauce wax even though I have my concerns knowing what is actually in the makeup of the wax. Generally wax gives you more control in to turns, and makes glide easier. Speed however, is less of a concern to me in the backcountry. The coefficient difference between an eco-friendly and a toxic fluorocarbon wax is very, very minimal. The durability is virtually the same between the two.

With that said, there is really no reason any recreational user needs to resort to a wax containing fluorocarbon or other added toxins when the technology and manufacturers are starting to step up to the environmental impacts of various waxes. Whichever wax you choose, be vigilant to heat the wax iron just enough the drip the wax. DO NOT allow the wax to smoke, or breath in the fumes! Preheat the iron for awhile to get the lower setting up to a suitable temp. Never apply the iron directly on to the PE) is a Ultra High Molecular Weight (UHMW) polyethylene" class="glossaryLink " target="_blank">polyethylene base without wax as this can damage the base pores. Use fiberlene between the base and the iron if necessary.

I believe structure is more important than wax type, unless you are racing to achieve a difference of seconds in speed.  Matching a finer structure on both the base and the wax during cold temps, and a more course structure during warmer temps is more of a concern. Copper and brass brushes are typically used prior to waxing to prep the surface. Stiff metal and / or steel brushes should not be used and are an obsolete technique. The wax structure brush you choose will make a big difference in performance. The all-purpose nylon brushes achieve the majority of structures. These bristles are course however, and will not remove wax in the finer structure. Horse hair and other finer bristle brushes can accomplish fine structure.

Waxing

A clothes or steam iron from a thrift shop will work just fine. Many wax manufactures claim that a manufactured waxing iron is the only way to control heat. I have actually found the opposite to be true. Out of curiosity, I used an infrared temperature monitor on three types of leading wax irons and the temp fluctuations, while minuscule, were all over the map. The clothes iron maintained heat within two degrees constant.

There are literally hundreds of videos and articles out there that show various techniques for waxing. The process is somewhat the same; prep, drip wax, spread wax, scrape, structure, and tune. I will very briefly touch on basics and emphasize key points that are often not mentioned.

swix wire brush
Step 1

Prep the base surface with a brass or copper bristle brush (not steel). This opens the pores and gets rid of impurities that may have worked their way in to the base. Remember you should wear a respirator when brushing or hot-scraping a wax that contains fluoros.

Citrus cleaner
Step 2

Clean the base thoroughly with a citrus cleaner and wipe all the impurities from the sintered base using a Scoth-Brite pad — gently, especially residual traces of glue from skins which will always work their way in to the pores. Keeping your base in good shape will prolong the life of the skin glue as well. Citrus cleaners found at auto parts stores will do the trick. I use a 20x concentrate and mix my own in a spray bottle. Dawn dish soap is another choice – diluted with warm water. Don’t fall for the marketing gimmick of toxic base cleaners.

remove micro-hairs
Step 3

Inspect for micro-hairs from the polyethylene base that will cause friction. If present, remove them gently with a steel scraper or Scoth-Brite pad. Follow over the area with an Omni pad.

caution
Caution!

Warm the iron to the lowest setting that will allow the wax to melt and drip. DO NOT allow the wax to smoke or breath fumes. Organofluorine breakdown products in heated wax are extremely toxic (see ‘Environmental and health concerns’ & ‘Caveat emptor’ sections below).

Drip wax from iron on to base surface
Step 4

Drip the wax on to the base surface. With the iron at a low setting move the melted wax across the surface.

spread wax across base with iron
Step 5

Spread the wax on to the base surface with the coolest setting possible while still maintain wax spread. Never allow the iron to touch the base without wax, this will damage the pores (e.g. heat sealing). If you are using a higher temperature wax you should use fiberlene between the base and iron.

allow wax to cool overnight
Step 6

Allow the wax to cool overnight at room temperature. Many people make the mistake of scraping soon after they wax. This pulls wax from the pores and is the number one culprit in base burn discussed in more detail in the previous section.

sCRAPE WAX FROM BASE SURFACE
Step 7

Scrape the wax with a plastic scraper from tip to tail in one motion. You want continuos straight lines. Do not use a metal scraper for removing wax. Keep your plastic scrapers sharp using a metal one. Lock the plastic scraper into a vise and starting at the far side, drag the metal scraper towards yourself in a relatively quick but controlled manner a few times. Good as new!

Nylon brush wax structure
Step 8

Using a nylon structure brush, go straight from tip to tail to add or enhance structure. For fine structure you can follow this in succession with a fine horse hair structure brush.

Tune edges
Step 9

Last step if necessary; debur and tune edges. Since this splitboard has a rocker, I detune a bit on the rocker areas with a demon stone.

 

Wax structure

A perfect mid-winter base and wax structure
A perfect mid-winter base and wax structure

In the previous section I covered structure theory, and the different types of structure for conditions. The same principle holds true for waxing; the smaller the snow crystals, the finer the structure required and visa versa. Likewise, in cold, dry snow such as the Rocky Mountain region (20°F and below), the structure should be fine and shaped to hold minimal water for the conditions. On cold crystalline snow (10°F and below), the base should be as smooth as possible so the points of friction are minimized. On amorphous, wet snow (20°F and above), a coarser structured snowboard base is better to minimize the points of friction. The idea is to move the free moisture away from the base and reduce suction. It is important to mention that a course structure is somewhat permanent.

Environmental and health concerns

I realize this isn’t going to be a popular topic to many out there, especially to those in the competition and manufacturing sectors. However, this is a broad message to all users, both recreational and professional. The common bond we all share is the passion for the mountains. With that said, we should all be stewards to the environment and do our part to protect what we are passionate about. The concerns about fluorinated waxes stem from the production process. There are many wax companies developing more eco-friendly waxes that are safer for the environment. Despite that, many of the wax companies basically deny any plausibility, the facts are there, and these companies are doing nothing more than protecting themselves and their profits. There is big money in competitive ski and snowboard races, and often these competitions are won by fractions of a second. You can quickly put the dots together and follow the underlying motives of these companies. Manufacturing fluoro products requires some nasty chemicals, including perfluorooctanoic acid (PFOA). These chemicals have ended up in the water streams near Dupont and 3M production facilities and have affected thousands of people. Ski and snowboard wax is a minuscule part of the bigger picture of fluorochemical processing. See the Environmental Protection Agency’s lawsuits against fluorochemical manufacturers in the US.[10]U.S. Environmental Protection Agency, (2013). Perfluorooctanoic Acid (PFOA) and Fluorinated Telomers, Retrieved November 29, 2014, from http://www.epa.gov/oppt/pfoa/.

A time trend study focusing on ski waxing technicians’ exposure to perfluorinated chemicals (PFCs) from fluorinated wax fumes was performed in 2007/2008. Levels of eight perfluorocarboxylates and three perfluorosulfonates were analyzed in monthly blood samples from eight technicians. Samples were collected before the ski season, i.e., preseason, then at four FIS World Cup competitions in cross country skiing, and finally during an unexposed five-month postseason period. The perfluorinated carboxylates perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) bioaccumulate, and continued exposure may contribute to elevated levels in ski technicians compared to the general population. The wax technicians’ median blood level of PFOA was 112 ng/mL compared to 2.5 ng/mL in the general Swedish population.[11]Nilsson H, Kärrman A, Westberg H, Rotander A, van Bavel B, & Lindström G. (2010). A time trend study of significantly elevated perfluorocarboxylate levels in humans after using fluorinated ski wax. Environ Sci Technol. 2010 Mar 15;44(6):2150-5.
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Caveat emptor

The exact contents of the waxes are seldom revealed by the manufacturers, but it has been shown that many of the glide waxes available on the market contain semifluorinated n-alkanes (SFAs) and perfluorinated carboxylic acids (PFCAs). Application of glide waxes to snowboards, downhill and cross country skis is performed in a similar way using an iron to melt the wax onto the base of the ski.[12]Kärrman A, Ericson I, van Bavel B, Darnerud PO, Aune M, Glynn A, Lignell S, Lindström G. (2007); Environ Health Perspect. 115(2): 226-230 This procedure causes a lot of smoke and fumes containing a blend of gaseous organofluorine compounds which are easily inhaled by the worker.[13]Yeung LWY, Miyake Y, Taniyasu S, Wang Y, Yu HX, So MK, Jiang GB, Wu YN, Li JG, Giesy JP, Yamashita N, Lam PKS. (2008); Environ Sci Technol. 42(21): 8140-8145[14]Young CJ, Furdui VI, Franklin J, Koerner RM, Muir DCG, Mabury SA. (2007); Environ Sci Technol.41(10): 3455-3461 Inhalation of organofluorine breakdown products are known to induce pulmonary edema and polymer fume fever, informally called Teflon Flu.[15]Loewen M, Wania F, Wang FY, Tomy G. (2008); Environ Sci Technol. 42(7): 2374-2379[16]Dinglasan MJA, Ye Y, Edwards EA, Mabury SA. (2004); Environ Sci Technol. 38(10): 2857-2865 Reduced fecundity have been observed with levels of PFOA found in the general population as well as developmental toxicity,[17]Russell MH, Berti WR, Szostek B, Buck RC. (2008); Environmental Science & Technology, 42(3):800-807 and hormonal disruption.[18]Martin JW, Chan K, Mabury SA, O’Brien PJ. (2009); Chemico-Biological Interactions. 177(3): 196-203 In addition, fluorotelomer alcohols demonstrate estrogen-like properties.[19]Hart K, Kannan K, Isobe T, Takahashi S, Yamada TK, Miyazaki N, Tanabe S. (2008); Environ Sci Technol. 42(19): 7132-7137 PFOA has been detected in industrial waste, stain resistant carpets, carpet cleaning liquids, house dust, microwave popcorn bags, water, food, some cookware and PTFE such as Teflon®.

The chemical has received attention due to litigation from the PFOA-contaminated community around DuPont’s facility, along with USEPA focus. Research on PFOA has demonstrated ubiquity, animal-based toxicity, and some associations with human health parameters and potential health effects. Additionally, advances in analytical chemistry in recent years have allowed the routine detection of low and sub-parts per billion levels of PFOA in a variety of substances.[20]Lau C, Butenhoff JL, Rogers JM (July 2004). The developmental toxicity of perfluoroalkyl acids and their derivatives. Toxicol. Appl. Pharmacol. 198 (2): 231–41. PFOAs were known to cause health issues but the company kept this fact in the closet for years until uncovered in the lawsuit. A team of experts revealed that it has found a “probable link” between PFOAs and human cancers, rebuffing DuPont’s longstanding contention that exposure to the chemical is harmless. The studies concluded that there was probably an association between PFOA exposure and six health outcomes: kidney cancer, testicular cancer, ulcerative colitis, thyroid disease, hypercholesterolemia (high cholesterol), and pregnancy-induced hypertension.[21]Nicole, W. (2013). PFOA and Cancer in a Highly Exposed Community: New Findings from the C8 Science Panel. Environmental Health Perspectives 121 (11–12): A340.

 

Purl Wax is equally committed to performance and the environment. Purl Microcrystalline Waxes contain no perfluorocarbons (PFCs) and the ingredients in our All Natural Waxes are exclusively obtained from natural and renewable resources.
Purl Wax is equally committed to performance and the environment. Purl Microcrystalline Waxes contain no perfluorocarbons (PFCs) and the ingredients in our All Natural Waxes are exclusively obtained from natural and renewable resources.

One has to read the wording carefully to understand the crafty misleading labels from some wax manufactures. Statements such as “biodegradable” is a misnomer. Perfluorooctanoic acid is very persistent in the environment, meaning PFOA persists indefinitely in the environment. Likewise, proclaiming that because some of their ingredients reside in food products somehow makes them safe is also misleading at best. My take from an industry background is this; despite the leveraging in the ski race industry which boons big dollars, be extremely skeptical of reading these proclamations. Do not allow wax to smoke, and by all means work in a well ventilated area. If you are scraping, or brushing any of the hybrid flouro waxes or combinations — wear a respirator! If you want even further reading to make up your own mind, despite the industry denial, there is a tantamount level of data to the contrary cited here;

[22]Hansen KJ, Clemen LA, Ellefson ME, Johnson HO. (2001); Environ Sci Technol. 35(4): 766-770[23]Chiappero MS, Argüello GA, Hurley MD, Wallington TJ. (2008); Chemical Physics Letters. 461(4-6):198-202[24]Conte L, Zaggia A, Sassi A, Seraglia R. (2007); J Fluorine Chem. 128(5): 493-499[25]Hämeri K, Aalto P, Kulmala M, Sammaljarvi E, Spring E, Pihkala P. (1996); Journal of Aerosol Science. 27(2): 339-344[26]Liesivuori J, Kiviranta H, Laitinen J, Hesso A, Hameila M, Tornaeus J, Pfaffli P, Savolainen H. (1994); Ann Occup Hyg. 38(6): 931-937[27]Patel MM, Miller MA, Chomchai S. (2006); Am J Emerg Med. 24(7): 880-881[28]Lemonick MD, McLaughlin L. (2006); Time. 167(24): 60-61[29]Fei CY, McLaughlin JK, Lipworth L, Olsen J. (2009); Human Reproduction. 24(5): 1200-1205[30]Fei CY, McLaughlin JK, Tarone RE, Olsen J. (2007); Environ Health Perspect. 115(11): 1677-1682[31]Apelberg BJ, Goldman LR, Calafat AM, Herbstman JB, Kuklenyik Z, Heidler J, Needham LL, Halden RU, Witter FR. (2007); Environmental Science & Technology. 41(11): 3891-3897[32]Astrup JA, Leffers H. (2008); International Journal of Andrology. 31(2): 161-169[33]Maras M, Vanparys C, Muylle F, Robbens J, Berger U, Barber JL, Blust R, De Coen W. (2006); Environ Health Perspect. 114(1): 100-105[34]Kärrman A, van Bavel B, Jarnberg U, Hardell L, Lindström G. (2006); Chemosphere. 64(9): 1582-1591[35]Nilsson H, Karrman A, Westberg H, Rotander A, van Bavel B, Lindstrom G. (2010); Environ Sci Technol. 44(6): 2150-2155[36]Gannon S, Johnson T, Serex T, Buck R. Adsorption, Distribution, And Excretion Of [Carbonyl-14C]-Perfluorohexanoic Acid In Rats And Mice In: Proceedings of the Society of Toxicology (SOT) Annual Meeting 2009, Baltimore, MD.
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Further reading

The bottom line is this, most backcountry enthusiasts are not concerned with fractions of a second in speed. Recreational users in general do not need this advantage. There are plenty of waxes out there such as Purl (purlwax.com) that are completely green and safe to apply and use. Furthermore they have less of an impact on the environment.  I have provided more than 150 additional citations for further reading (cited below in References). You simply cannot deny the science and studies that are out there. I would urge other backcountry and recreational users to keep in mind the industry practices you are supporting by purchasing products.

[37]Record of Perfluorooctanoic acid in the GESTIS Substance Database from the IFA, accessed on 5 November 2008[38]Prevedouros K, Cousins IT, Buck RC, Korzeniowski SH (December 2006). “Sources, fate and transport of perfluorocarboxylates”. Environ. Sci. Technol. 40 (1): 32–44.[39]Goss KU (July 2008). “The pKa values of PFOA and other highly fluorinated carboxylic acids”.Environ. Sci. Technol. 42 (2): 456–458.[40]Cheng J, Psillakis E, Hoffmann MR, Colussi AJ (July 2009). “Acid dissociation versus molecular association of perfluoroalkyl oxoacids: Environmental implications”. J. Phys. Chem. A 113 (29): 8152–8156.[41]Rayne S, Forest K (June 2010). “Theoretical studies on the pKa values of perfluoroalkyl carboxylic acids”. J. Mol. Struct. (Theochem) 949 (1–3): 60–69.10.1016/j.theochem.2010.03.003.[42]Nicole, W. (2013). “PFOA and Cancer in a Highly Exposed Community: New Findings from the C8 Science Panel”. Environmental Health Perspectives 121 (11–12): A340.[43]Emmett EA, Shofer FS, Zhang H, Freeman D, Desai C, Shaw LM (August 2006).”Community exposure to perfluorooctanoate: relationships between serum concentrations and exposure sources”. J. Occup. Environ. Med. 48 (8): 759-70.[44]Clapp, Richard; Polly Hoppin; Jyotsna Jagai; Sara Donahue. “Case Studies in Science Policy: Perfluorooctanoic Acid”. Project on Scientific Knowledge and Public Policy (SKAPP). Retrieved 2008-12-19.[45]Kennedy GL, Butenhoff JL, Olsen GW, et al. (2004). “The toxicology of perfluorooctanoate”.Crit. Rev. Toxicol. 34 (4): 351–84.[46]Giesy JP, Kannan K (April 2002). “Perfluorochemical surfactants in the environment”. Environ. Sci. Technol. 36 (7): 146A–152A.[47]Lau C, Butenhoff JL, Rogers JM (July 2004). “The developmental toxicity of perfluoroalkyl acids and their derivatives”. Toxicol. Appl. Pharmacol. 198 (2): 231–41.[48]Ullah, Aziz (October 2006). “The Fluorochemical Dilemma: What the PFOS/PFOA fuss is all about” (PDF). Cleaning & Restoration. Retrieved 2008-09-24.[49]Lee, Jennifer 8. (15 April 2003). “E.P.A. Orders Companies to Examine Effects of Chemicals”.The New York Times. Retrieved 15 May 2009.[50]“3M United States: PFOS PFOA: What is 3M Doing?”. 3M Company. Retrieved 2009-01-05.[51]Weber, Joseph (5 June 2000). “3M’s Big Cleanup – Why it decided to pull the plug on its best-selling stain repellent”. Business Week (New York: McGraw-Hill) (3684): 96.[52]Savu, P (1994). “Fluorinated Higher Carboxylic Acids”. Kirk-Othmer Encyclopedia of Chemical Terminology. John Wiley & Sons, Inc.[53]Goeden, Helen (June 2008). “Issues and Needs for PFAA Exposure and Health Research: A State Perspective” (PDF). PFAA Days II. Minnesota Department of Health. U.S. EPA – Research Triangle Park. Retrieved 2008-12-02.[54]Lehmler, HJ (March 2005). “Synthesis of environmentally relevant fluorinated surfactants—a review”. Chemosphere 58 (11): 1471–96. 10.1016/j.chemosphere.2004.11.078.[55]Ylinen M, Hanhijärvi H, Peura P, Rämö O (November 1985). “Quantitative gas chromatographic determination of perfluorooctanoic acid as the benzyl ester in plasma and urine”. Arch. Environ. Contam. Toxicol. 14 (6): 713–7.[56]“PFOA in Norway TA-2354/2007”. Norwegian Pollution Control Authority. 2007. p. 6. Retrieved 6 April 2009.[57]“Information on PFOA”. DuPont. Retrieved 23 May 2009.[58]Siegle, Lucy (11 October 2009). “Do environmentally friendly outdoor jackets exist?”. The Observer (London). Retrieved 25 October 2009.[59]Kudo N, Kawashima Y (May 2003). “Toxicity and toxicokinetics of perfluorooctanoic acid in humans and animals”. J. Toxicol. Sci. 28 (2): 49–57.[60]Kudo N, Suzuki-Nakajima E, Mitsumoto A, Kawashima Y (September 2006). “Responses of the liver to perfluorinated fatty acids with different carbon chain length in male and female mice:in relation to induction of hepatomegaly, peroxisomal beta-oxidation and microsomal 1-acylglycerophosphocholine acyltransferase”. Biol. Pharm. Bull. 29 (9): 1952–7.[61]Gordon SC (September 2010). “Toxicological evaluation of ammonium 4,8-dioxa-3H-perfluorononanoate, a new emulsifier to replace ammonium perfluorooctanoate in fluoropolymer manufacturing”. Regul Toxicol Pharmacol 59 (1): 64–80.[62]Sandy, Martha. “Petition for Expedited CIC Consideration of Perfluorooctanic Acid (PFOA)”. The State of California, Office of Environmental Health Hazard Assessment, Cancer Toxicology and Epidemiology Section, Reproductive and Cancer Hazard Assessment Branch. Retrieved2008-09-27.[63]C, Anitole K, Hodes C, Lai D, Pfahles-Hutchens A, Seed J (October 2007).“Perfluoroalkyl acids: a review of monitoring and toxicological findings”. Toxicol. Sci. 99 (2): 366–94.[64]Michael McCoy (November 2008). “Dyneon Phasing Out Perfluorooctanoate”. Chemical & Engineering News 86 (46): 26.[65]Renner, Rebecca (June 2003). “Concerns over common perfluorinated surfactant”.Environ. Sci. Technol. 37 (11): 201A–2A.[66]Siegemund, W. Schwertfeger, A. Feiring, B. Smart, F. Behr, H. Vogel, B. McKusick (2005). “Fluorine Compounds, Organic”. Ullmann’s Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH.[67]USEPA (7 March 2006). “Premanufacture Notification Exemption for Polymers; Amendment of Polymer Exemption Rule to Exclude Certain Perfluorinated Polymers; Proposed Rule” (PDF).Federal Register 71 (44): 11490.[68]Salager, Jean-Louis (2002). “FIRP Booklet # 300-A: Surfactants-Types and Uses”. 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Conclusion

This concludes the three-part series. In Part One I covered the forces effecting movement on the snow. In Part Two I touched on base construction, and base structure theory. The physics of this series can be complex, but it’s actually easy to understand. With a basic understanding of the dynamics involved you can prepare your equipment and have a better understanding of how conditions impact riding.

Part 1: Forces Effecting Movement
on the Snow

Part 1: Forces Effecting Movement on the Snow

Part 2: Snowboard Base Construction

Part 2: Snowboard Base Construction

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References   [ + ]

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149. ↑ Ken Ward, Jr. (28 September 2009). “Federal judge throws out most of C8 suit against DuPont”. The Charleston Gazette.
150. ↑ Michael Janofsky (15 December 2005). “DuPont to Pay $16.5 Million for Unreported Risks”.The New York Times. Retrieved 23 November 2009.
151. ↑ Goodwin, C.J. “Rhodes, et al. v. E.I. Du Pont De Nemours and Company” United States District Court for the Southern District of West Virginia. Case Number, 6:06-cv-530 (30 September 2008). Retrieved 12 October 2008.
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153. ↑ Renner R; Christen, Kris (2006). “Scientists hail PFOA reduction plan”. Environ. Sci. Technol. 40(7): 2083.
154. ↑ “SAB Review of EPA’s Draft Risk Assessment of Potential Human Health Effects Associated with PFOA and Its Salts” (PDF). U.S. Environmental Protection Agency Science Advisory Board. 2006-05-30. p. 2. Retrieved 2008-09-21.
155. ↑ Mid-Atlantic Enforcement (10 May 2007). “Fact Sheet: EPA, DuPont Agree on Measures to Protect Drinking Water Near the DuPont Washington Works”. United States Environmental Protection Agency. Archived from the original on 18 January 2008. Retrieved 11 May 2008.
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158. ↑ Anke Schaefer; Barbara Booth; Naomi Lubick; Kellyn S. Betts (2006-12-01). “Perfluorinated surfactants contaminate German waters – Mislabeled waste in fertilizer leads to a water scandal”.Environ. Sci. Technol. 40 (23): 7108–14.
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