Resistance to penetration by liquids is a process in which a chemical moves through pores, seams, apertures or essential openings in a material or finished item of a clothing. Repellency is the ability of a fabric to shed liquid that is applied to the surface of a fabric. Penetration and repellency is measured according to ISO 6530. This test is know a the "gutter-test". Reference chemicals for penetration and repellency testing are: 30 % Sulphuric acis, 10 & Sodium Hydroxide, o-Xylene, Butan-1-ol. Chemical protective clothing, Category III, Typ 6 requires a liquid repellency level of 3 for at least one of the four chemicals and a resistance to penetration at a performance level of at least 2 for one of the 4 chemicals. The peformance level for Penetration and Repellency is listed in the Instruction for Use for the specific garment and in SafeSPEC(TM) under Data/Penetration and Repellency. Measuring the resistance to penetration and repellency is a fabric test and only applicable for garments. The test is not required for the Certfication of Partial Body Protection.

These fabrics have not been tested for permeation. Therefore no data are available.

ProShield® FR garments are antistatically treated inside and outside. ProShield® 10 white and ProShield® 10 blue and ProShield® 30 garments are antistatically treated inside. Easysafe garments are antistatically treated on the outside. ProShield® Proper and ProShield®Polyclean are antistatically treated for comfort only.

The size of the chemical protective suit selected is very important since proper fit is part of proper protection. Furthermore, a good fit ensures a protective suit is comfortable and avoids extra heat up which can be caused by too big suits. By poorly fitting garments either too small or too large you have an increased risk of tearing the garment and of being restricted in your movements or getting caught in machinery, which can adversely affect your ability to carry out your work safely.

Ideally a second person dressed in a chemical protective suit and other appropriate personal protective equipment provides assistance. To avoid a contamination while undressing the following order is recommended: If the garment is heavily contaminated it recommended to wet it in case of dust or to shower in case of liquid Clean the outer gloves arm parts and zipper area of the garment by using wipes Remove the outer glove while keeping on the inner glove Open the zipper carefully Remove the garment turning it inside out and pull it down to knees. Pull your feet out of the garment carefully Pull the garment together inside out - so the garment can be disposed of If wearing one, remove the mask Remove the inner glove

In the USA, OSHA 29CFR1910.132 states that it is the responsibility of the employer to:

• Perform a hazard assessment
• Select PPE and inform employees
• Fit and train employees on use, care and service life of PPE

Tychem® garments can be worn in ambient temperatures of -13°F (-25°C) to 120°F (49°C).
In colder environments, Tychem® garments can become stiff. If cold enough, the fabric may even become brittle. Please be aware that the heat stress of the wearer becomes a greater concern in higher ambient temperatures. At higher temperatures, chemical hazards can become more aggressive. Breakthrough times and permeation rates may change at higher temperatures. The published permeation data per ASTM F739 is performed at ambient temperatures (approximately 72-81° F ; 22-27° C).

Caution: Tychem® fabrics offer little or no thermal insulation to protect the wearer's skin from prolonged exposure to hot or cold.

When working in explosive environments it is recommended to first control the relative humidity since in extremely dry environments with a relative humidity below 25%, the antistatic finish on the garments may no longer function. The chemical protective suit must be correctly and continuously grounded via electrostatic dissipative shoes, floor and / or grounding cable. If the wearer of an antistatically treated garment is not connected to a grounded surface, the wearer/garment might remain charged.

In general, garments must be correctly and continuously grounded by contact with electrostatic dissipative shoes, floor and/or grounding cable to the antistatic treated side of the garment. If the wearer of an antistatically treated garment is not connected to a grounded surface, the wearer/garment will remain charged. It also important to consider that electrostatic charges may also build up on ancillary equipment such as breathing apparatus and other devices. Therefore those must be separately grounded when worn in conjunction with a garment. Attention must be paid to the local humidity levels since in dry environments with a relative humidity below 25%, the antistatic finish may no longer function effectively. Garments with attached socks cannot be grounded via the shoes.

A proper dressing is a must for proper protection. There are a couple of steps to be considered : Check if the place of dressing is contaminant free Check the garment, check if type and size are appropriate, if the zipper is working and if the clothing material and seams are defect free Check compatibility of other Personal Protective Equipment (PPE) with protective suit selected as well as their functionality Decide whether normal working clothing or special underwear shall be worn under the garment Take off your shoesFirst enter the garment with your feet then the arms and pull it over your back Close the zipper up to chest high Put on safety boots Pull the garment leg over the boot If a mask is required for the considered task one shall put it on at this stage following the instructions given by the mask manufacturer Once the mask is put on, the hood is put on making sure that it fits tightly to the mask. Ideally a second person controls the tightness around the mask. If no second person is available it recommended to do the check with a mirror. Close the zipper as far as possible and make sure that the zipper flap covers the entire zipper. Put on the gloves (ideally inner and outer glove), if only one glove is used put the gauntlets below the sleeves. For additional protection the hood can be taped to the mask and the gloves to the sleeves. Furthermore it is recommended to tape the zipper flap.

When selecting protective clothing, DuPont recommends taking four steps to ensure an appropriate selection and successful implementation. Those steps are: 1. Risk assessment: Before searching for protective clothing, it is recommended to do a detailed assessment of the nature of the hazard, the type of exposure and the working environment. 2. Defining the appropriate garment type: Once a risk assessment has been made the appropriate garment type can be defined. 3. Research: Since there a variety of limited-use protective clothing available in the market one should consider certain performance criteria for the garment selection process, such as for example, protection, durability, comfort, quality, compatibility with other personal Protective equipment, environmental compatibility and value for money. Information on type certification, barrier performance and fabric physical properties can be gained from the use instructions supplied by the manufacturer while information on other properties, for example, user friendliness, protection performance in real applications amongst others can only be gained in a wear trial. 4. Testing for success: After having selected a Tyvek® chemical suit matching the analysed requirements it is recommended to carry out a wear trial under real working conditions to gain feedback from the employees. Furthermore, the employees feel integrated in the garment choice which may result in less acceptance problems when implementing the selected garment.

In terms of chemical protective clothing, penetration is the passage of a chemical through a pore or opening in the barrier material. Permeation is the absorption, diffusion and desorption of a chemical through the barrier material at the molecular level.

Generally it is up to the wearer to decide on his/her personal underwear. For higher comfort we recommend the following: wear at least one layer of underwear under the chemical protective suit select underwear with long arms and legs underwear made from traditional fabric such as blended woven structures underwear made from high-performance fibres

Chemical protective clothing can interfere with the natural regulation of body temperature. This can lead to a rise in core body temperature and heat stress. Implementing a conservative work/rest schedule or using a cooling system like the DuPont™ Cool-Guard® vest may be effective in reducing heat stress. (Note: Do not wear cooling vests in potentially flammable or explosive environments.)

Be aware of the symptoms and treatment of heat stress. If you or your co-workers have symptoms of heat stress such as nausea, dizziness, high heart rates, or excessive heat build-up, leave the work area immediately and remove the ensemble as quickly as possible after decontamination and seek professional care.

The maximum length of time the chemical protective clothing can be worn depends on variables such as the air supply, ambient conditions, climate inside the ensemble, physical and psychological conditions of the wearer, work rate and work load. The TLV® pocket guide from the American Conference of Governmental Industrial Hygienists (ACGIH, Cincinnati) provides corrected heat stress limits for some garments. Similar information is available on the federal OSHA web site (www.OSHA.gov). The WBGT correction factor for chemical protective garments is at least 10°C or higher for chemical garments made of impervious films (such as Tychem® garments) and covering the entire body (hooded coverall or encapsulating designs). For Tyvek® coveralls, the WBGT correction factor is 2°C with a hood and 1°C without a hood.

The following typical mistakes that can happen when working with protective clothing have been reported to us: Opening of garment or mask while working in the risk zone. Interrupting the task and leaving the dangerous zone with contaminated garment and moving to other zones like offices. Carelessness of wearers with regard to hot surfaces, sparks or sharp edges. Employees with a passive role in the dangerous zone do often not wear protective clothing. No or false grounding of garments due to insufficient knowledge or underestimation of risk of electrostatic charging. Under protection: wrong fabric selection or garment tightness level for the hazard. Loss of protection if the suit becomes abraded or damaged and is not changed.