We would like to note the policy of returns. Because of the highly divergent nature of the work environment, it is impossible to issue an indefinite guarantee on safety footwear. This encompassing guarantee would invite abuse from unscrupulous sectors. Instead, each claim is assessed individually to determine weather or not the footwear has provided the wearer “FAIR WEAR” with in his specific work environment.
Footwear will carry a guarantee of 1 months from purchase should the fault be due to factory defect.
Any footwear older than 1 months from purchase will not be accepted for return. The customer must also ensure when purchasing footwear in great quantity to rotate their stock on a regular basis.
Naturally as an SABS manufacturer, Lemaitre accepts full responsibility for unprovoked footwear faults arising from material or manufacturing error.
In instances where doubt exists, the question is asked whether the following safe boundaries were exceeded:-
- WATER - Polyurethane / leather footwear is designed to be water-resistant, not water proof. In areas where there is constant exposure to water, employees should wear gumboots, not leather footwear.
- OIL - Polyurethane footwear is highly resistant to oil, although life of footwear will be prolonged if excess is occasionally removed from the surface of the leather.
- ACIDS - Polyurethane exhibits good resistance to a broad spectrum of acids, providing that they are reasonably diluted. Concentrated Hydrochloric, Sulphuric and Nitric acids will attack even metals, so it is unreasonable to expect polyurethane to endure prolonged contact with them. (See Chemical Resistance Table in our borchure)
- HEAT - polyurethane footwear is resistant to temperatures up to 90 degrees Celsius. Specialized heat resistant footwear is required for environments exceeding 90 Degrees.
- MINES - safety footwear is well suited for work on open cast mines, but should be worn with circumspection below ground where a noxious gas hazard exists.
- CEMENT - Cement in conjunction with water, frequently dehydrates the leather in safety footwear, hardening it and ultimately corroding the PU sole. PU footwear still acquits itself well on construction sites however, although the average lifespan of the footwear will be lower than the general industry.
All reasonable claims for faulty footwear will be met but in any instances of disagreement or dispute the matter shall be settled by discussions between the factoryr and the customer or failing which, by referral to the South African Bureau of Standards in Pretoria.
WHAT IS POLYURETHANE?
The majority of safety footwear styles are manufactured using what is referred to as “direct injection moulded double density polyurethane” as a soling material. A bit of a mouthful? Perhaps, but the term is easily understood if explained bit by bit.
Polyurethanes are organic polymers made by the reaction of diiosocyanates with other difunctional compounds such as glycols. Foamed polyurethanes such as those used in the soles of Lemaitre footwear, result from the reaction of diisocyanates with polyesters. These reactions liberate bubbles of carbon dioxide that remain dispersed throughout the product.
Single density An outdated, though nonetheless still viable method of soling safety footwear, is single density polyurethane. Whereas double density polyurethane soled boots and shoes utilise both a hard wearing outsole and lower density comfort midsole, single density footwear comprises only a single layer of "mid" density polyurethane
Although the relative simplicity of single density polyurethane manufacture means that there are cost advantages over its double density counterpart, the "mid" density polyurethane has the potential to wear very quickly, or crack along the flex line of the footwear.
Double density simply means that the sole comprises two layers. The lower layer, or outsole, is a higher density polyurethane which ensures that the footwear is hard wearing. The middle layer, or midsole, is a medium density polyurethane which acts like a cushion, ensuring that the footwear is comfortable.
Direct injection moulded points to the fact that the soles are moulded directly onto the leather upper without the use of adhesives or stitching. This is possible because of the dramatic speed at which monomers polymerise to form network polyurethanes, a process that is so rapid, that articles may be fabricated by injecting the reacting monomers directly into a mould.
WHY CHOOSE POLYURETHANE AS A SOLING MATERIAL?
Much of the beauty of polyurethane lies in understanding that the soles of safety footwear comprise a latticework of polyurethane surrounding millions of carbon dioxide bubbles formed during the injection process. You are, in a sense, walking on air.
Because the gas displaces a significant portion of the soling material, the resulting product is more lightweight than denser alternates such as rubber. It is estimated that for every additional 100 grams of weight contained in a pair of boots or shoes, the wearer will expend an additional 1% of energy daily. With this in mind, it makes good sense to choose a lightweight product for the working environment.
WHY CHOOSE NITRILE RUBBER AS A SOLING MATERIAL?
Nitrile rubber is a product of synthetic rubber research during and between the two world wars. Formed in an emulsion process using free-radical initiators, nitrile rubber shows outstanding resistance to oil, with hydrogenated versions demonstrating very high resistance to thermal and oxidative deterioration.
These properties make it an ideal soling material for use on specialised heat resistant safety footwear, such as the Heat Resistant Range . The sole used on these items is comprised of a specially formulated nitrile rubber resistant to 300 degrees Celsius - ideal for use in foundries, smelters, tapping floors and industries producing hot metal shavings during manufacture.
POLYURETHANE AND THE ENVIRONMENT
Because polyurethane has organic origins, it is biodegradable over time. In a society where increasing attention is being focussed on protecting our fragile environment, many progressive companies are insisting that, as far as possible, consumables such as safety footwear conform to environmentally sound specifications. The process of biodegradation is slow, taking place over many years, ultimately rendering the polyurethane to a number of benign compounds.
HYDROLYSIS
In both chemistry and physiology, hydrolysis is a double decomposition reaction, with water as one of the reactants. Hydrolysis can affect safety footwear. Simply put, the oxygen atom in water bonds with the carbon atom of the esters in the polyurethane. This carbon – oxygen bond is unstable, and eventually also breaks down, leading to the gradual disintegration of the polyurethane.
Hydrolysis is safety footwear only becomes a serious issue when four factors combine to create the ideal environment: water, temperature, darkness and time. Lengthy storage (longer than a year) in a hot and humid climate is potentially the perfect catalyst for hydrolysis.
New polyurethane formulations and the addition of a chemical called Vinyzene significantly retard the process of hydrolysis, but following a few simple steps can almost eliminate it entirely:
- Rotate stock frequently on a first in, first out basis. Do not keep polyurethane soled footwear on the shelf for longer than a year.
- Be aware of the climate in which the footwear will be worn.
- Encourage the wearer to properly aerate the footwear after use.
- Do not wear polyurethane soled footwear where gumboots would be more suitable.
STEEL TOECAPS
Steel toecaps are manufactured from high carbon steel and heat treated for maximum impact protection. The toecaps used in Safety Footwear are "full flange caps" measuring 6.0 mm thereby ensuring the best possible protection in the event of a heavy object falling on a wearer's foot.
All toecaps are imported and have been made under strict quality control systems according to various national safety footwear standards. The most important of these tests is the "impact test" where the South African Standard requires an Impact Performance of 200 joules.
SABS 1167 and SABS 1114 Specifications require the following standards:-
- Impact resistance at an energy level of 200 joules with a minimum internal clearance of 21.0 mm on a size 8/262.
- Safety toecap should not develop any cracks through which light can be seen.
- Safety toecap should be Corrosive Resistant.
- Minimum internal length should be 39.0 mm on a size 8/262.
- Flange width should be at least 3.0 mm.
In assessing the suitability of any Steel Toecap, care must be taken when comparing the different dimensions. The most important measurements are-
- External length
- External width
- External height
No one measurement can be taken as an indication of its suitability but all three measurements need to be analysed. E.g. a toecap which has a higher External width does not necessarily give the best comfort as it may have an excessive External length which means the wearer's foot will need to go deeper into the actual toecap. The External height is also important especially when the wearer spends a lot of time working on their haunches.
WHY WEAR FOOT PROTECTION?
Every workplace, no matter how safe it may appear, contains hazards, which pose the risk of injury. Most accidents and injuries can, however, be prevented by anticipating potential danger and taking steps to reduce or eliminate them. Wearing safety footwear is one simple way of reducing the risk of serious injury to two very important appendages – your feet.