Cleanroom consumables are a major expenditure for cleanroom users. Karen Rossington, on behalf of Nitritex, looks at current factors affecting costs and offers expert advice on how to control them.
Sales of cleanroom consumables and hardware will exceed US$10.3bn (€7.6bn) in 2011, according to the latest report from McIlvaine’s Cleanroom World Markets. Gloves are the single biggest cleanroom consumable, with wipes in second place. Most cleanrooms spend an estimated 40% of their consumable budget on gloves.1 Reusable and disposable garments are equal in revenue terms, but not in unit sales, as more disposable garments are purchased.
Fuelling this consumable revenue growth, especially in the area of gloves, is the significant rise in raw material pricing that has been experienced over the past 8–12 months in both natural latex and nitrile latex. As the raw material contributes around 55% of the overall cost of a non-sterile cleanroom glove, in many instances at least, some proportion of this increase has been passed on to the customer as higher end-user prices.
In simple terms, the raw latex market is facing a period of high demand and low supply, leading to significant increases in the raw material price. Figure 1 shows the latex price in US dollars per kilo from July 2009 to April 2011.2
Reasons contributing to the low supply and high demand include:
- The “wintering” season, when rubber trees produce less latex. This period normally ends in April.
- Demand from China, especially rubber for tyres, is continuing to increase
- The flood situation in Southern Thailand and Northern Malaysia, the worst for 10 years, disrupted harvesting and damaged plantations
- Global concerns on a shortfall in latex production have encouraged speculative trading, further driving up the cost of the raw material
Such was the exceptional increase in pricing that towards the end of 2010, the Malaysian Rubber Glove Manufacturers’ Association (MARGMA) advised its members to raise sales prices accordingly.3 As the wintering season is now over, this, coupled with additional planting that is now coming to maturation is leading to increased supply and therefore more stable prices. Opinion differs on the future outcome; supply is increasing, but some experts predict that even with an expected increase in output, demand will outstrip supply until 2020.4 The global demand for rubber gloves has not slowed down and continues to grow at an annual rate of between 8% and 12%, thanks to new demand from emerging economies.
Other experts believe there is essentially no shortage in the supply of natural rubber outside the wintering season, and other factors, such as the increasing switch to nitrile, the release of buffer stocks from manufacturers and the reduction in demand for rubber in Japan after the tsunami, will help to balance supply and demand.5 Prices are stabilising, but are unlikely to fall to pre-2010 levels.
So as huge consumers of latex gloves, what can cleanroom users do to mitigate the increase in cost of latex gloves? Some operators are switching to nitrile. This switch has resulted in higher demand and a subsequent increase in the raw material price of nitrile rubber from $1,315 (€967.4) per 1000kg in April 2010 to $2,110 (€1,552) in July 2011.
BioClean Fusion – a cost-effective polychloroprene glove that provides latex-like fit and feel
However, there are other alternatives to latex gloves. One option is polychloroprene gloves such as BioClean Fusion. These gloves are manufactured from polymers of chloroprene (2-chloro-I, 3-butadiene), which form a petroleum-based, cross-linked film providing barrier protection and performance, similar to that of latex. They also have excellent antistatic properties.
Polychloroprene gloves have elasticity that is very close to that of latex, providing comfort that is comparable to latex and a fit much closer to latex than other alternatives. With a modulus (force required to stretch the glove) very similar to natural rubber latex, they are very comfortable to wear for long periods of time. Moreover, because polychloroprene contains no natural latex proteins, there is no chance of Type 1 allergic reactions.
Choice of garments
The choice of cleanroom garments breaks down fundamentally into three options – disposable, reusable (laundered) or a combination of the two. The disposable option can be further divided into single use disposable or limited life (multiple use but non-laundered). For reusable garments there are typically two distribution systems:
- Pool stock – a range of sizes to accommodate all wearers. Virtually all sterile facilities use this system.
- Wearer dedicated – garments are identified by a wearer name or number.
The main influencing factors to decide between disposable and reusable garment systems are the requirements to give the right level of containment, the number of changes of garb required by each operator per day, and the number of occasional visitors into the controlled area.
Table 1 shows the suggested garment system and level of garment changes for different cleanroom grades.6 The number of changes per week is probably the key factor in deciding whether it is more cost-effective to launder reusable garments or deploy single-use garments. Changes are defined as the number of garments that are cleaned and packed for one staff member working in the cleanroom in one week. This is irrespective of the total number of staff working in the cleanroom.
| Table 1: Garment system and level of changes for different cleanroom grades 6 | ||||||
| Cleanroom classification standards | ||||||
| ISO 14644 | ISO-3 | ISO-4 | ISO-5 | ISO-6 | ISO-7 | ISO-8 |
| US Fed. Std. 209 | 1 | 10 | 100 | 1.000 | 10.000 | 100.000 |
| GMP-guideline EU | A/B | C | D | |||
| Garment type | ||||||
| Undergarments | R | R | R | AS | AS | AS |
| Hair cover (bouffant) | R | R | R | R | R | R |
| Hood | R | R | R | AS | AS | AS |
| Coat | NR | NR | AS | AS | R | R |
| Coverall | R | R | R | R | AS | AS |
| Two piece | NR | NR | AS | AS | AS | AS |
| Overshoes | NR | NR | AS | AS | R | R |
| Overboots | R | R | R | R | AS | AS |
| Suggested frequency change | Per entry | Per entry | Per entry 1 x Day | 3 x/week | 2 x/week | 2 x/week |
| R = Recommended NR = Not Recommended AS = Application Specific | ||||||
As a general “rule of thumb”, the break point is approximately 10 changes per week. For facilities with more than 10 changes per week it is usually more cost-effective to opt for reusable laundered garments, using an independent cleanroom laundry to supply, maintain, clean, pack and manage the necessary garment system. Fewer than 10 changes per week means disposable or limited life garments will be more cost-effective. Figure 2 shows a more detailed breakdown, demonstrating that the costs become more favourable to use reusable garments at around the level of 10 garment changes per week based on a three-year contract.
It is not necessary to stick with just one or the other; the most cost-effective decision may be a blend of the two options. Take the number of visitors, for instance: if the number of visitors to the facility is small, then holding disposable garments just for visitors is a more economic option than holding numerous sizes of reusable garments. This does not necessarily add to the number of suppliers, as manufacturers, such as Nitritex, will be able to offer both disposable and laundered options.
Once a reusable system is decided upon, consideration needs to be given to the choice of purchase, lease, lease-to-own or rental. Rental tends to imply a comprehensive service where a single price covers the cost of the garment and its processing. Charges are levied week-on-week, regardless of whether the garment is used. Leasing, or split rental, normally shows a separate charge for the garments that is constant, regardless of use, and the laundry processing, which is a variable item.
When considering purchasing garments do remember that the size distribution within the facility is continually changing and you could be left with a large quantity of unneeded garments. Leasing or renting garments may come at a higher price but this should include the ability to return unused garments and change the size distribution. Lease-to-own means no residual charges at the end of the contract. The Cleanroom Laundry, part of the Nitritex Group, is able to discuss these options in detail and recommend the most cost-effective option for your facility.
Figure 2: Single-use (disposable) vs full rental – payback period 10 changes per week, 3-year period
Other ways to keep control of costs are to regularly review and adjust inventory levels to reflect current needs, as inventory levels will be reflected in the cost. Dependent on the number of garments, this review of inventory could be carried out every month, particularly for facilities with 200 or more wearers, or quarterly with fewer wearers.
Damage prevention
Look after the garments; they are costly and will degrade so take steps internally to prevent damage. Lost or damaged garments can add 8–10% to the overall cost of your garments.7
The three most common causes of damaged garments are equipment snags, inappropriate use and poor de-gowning habits.
Wearers should be educated as to what constitutes damage and what does not. Make it easy for operators to segregate damaged garments and ensure they get repaired. Garments not correctly rejected as damaged are often re-laundered multiple times without being segregated for repair, thereby shortening the life of the garment.
Each party must have a clear understanding of the point at which it becomes uneconomic and unrealistic to repair a garment and must opt for a replacement. The supplier’s reputation, industry knowledge and experience in the cleanroom environment provide additional security for any cleanroom operator seeking a new laundry provider. Detailed reports on garment lifecycle, repairs and user compliance should be available from the supplier to provide information for efficient cleanroom operation and control of costs.
A major change in repair costs typically signifies a new issue that requires attention. Proper management of garments, and verifying that users adhere to correct protocols, are essential to ensure garment life is maximised and wastage reduced.
End users have a significant role to play in controlling garment costs. Cleanroom operators can contribute to inflated laundry bills, not just through lack of control of garments, but also through overuse if their needs are not met.
It is in the changing room that operators make choices every day that can influence the cost and effectiveness of a cleanroom garment programme. Every time an operator opens three sealed garments to find one that “feels” right, or an engineer’s suit is moved from their peg and they have to open a new one, decisions are being made that inflate a facility’s garment costs.
Analysis carried out in the US showed that the rate of overuse in a relatively small cleanroom facility was one third above the target level; this was found to be not an uncommon level of overuse.8
Consider the experience of the wearer and involve them in the process. A clear view of the cleanroom operative’s perspective of the garment and gowning process will help when engaging them to become part of the solution. Identify and address garment issues both systemically and individually: in the long run this will eliminate the wearer’s frustrations and reduce levels of non-compliance and overuse.
With consumable costs forming such a significant part of the operational costs of the cleanroom, and price increases in not only raw materials but also energy, packaging and delivery costs all spiralling well above inflation, it makes commercial sense to conduct periodic reviews of the consumables used in the cleanroom. Choices in the type of product used, and routes of supply, coupled with attention to usage rates and compliance, can all reduce consumable budgets without compromising the quality of the product.
References
1. Global Society for Contamination Control Website. Jan 2011
2. LembagaGetah Malaysia – Malaysian Rubber Board
3. Shen Wei USA Disposable Rubber Glove News
4. VietNam News “Short Supply to Benefit Rubber Industry”
5. Tan Sri Lim Wee-Chai, StarBizNews
6. Institute of Environmental Sciences and Technology IEST- Recommended Practice RP-CC003.3
7. D.J.Netz, Tony Rutt, Controlled Environments Nov 2004
8. D.J Netz, T. Rutt, Controlled Environments Sept 2006
