Dosimeters cloth

Among the first dermal dosimeters used in exposure research were 4 x 4-in cellulose or gauze patches which were pinned to the outer and inner surfaces of clothing or vests which farm workers would wear during the application or re-entry phase of the smdy. These patches were easy to manufacture and when pinned to the shirt or pants of the worker made for an easily used dosimeter pad. The major advantage to the use of the patch to estimate worker exposure was this method s ability to differentiate the relative contributions of pesticide residues to different parts of the worker s body. This sampling technique in turn could lead to recommendations (i.e., the use of... 

After donning the outer dosimeter or clothing, the volunteer will then put on his/her socks and shoes. Usually clean, unworn socks are provided to avoid crosscontamination of the inner dosimeter with the socks from prior workdays. New shoes are also provided to the volunteer, again to avoid cross-contamination issues. On occasion, regular pre-worn shoes and socks may be used for the volunteer if crosscontamination of samples is not an issue. 

Selection of the type of whole-body dosimeter is important. Inner whole-body dosimeters are usually white, 100% cotton, long underwear purchased from a variety of clothing outlets and stores. One- or two-piece inner whole-body dosimeters are common. Outer whole-body dosimeters can range from hand-made cotton coveralls to shirts and pants bought directly off the shelf at local retail stores. Outer whole-body dosimeters can also be purchased from wholesale clothing outlets. Outer whole-body dosimeters may be any color and may also be 100% cotton or mixed materials, depending on the purpose for which the outer whole-body dosimeter is to be used. For example, one may want to use a coverall as an outer whole-body dosimeter. This would be acceptable even if the coverall were not white and not 100% cotton provided that the fabric did not contain interfering analytical components. 

A 1982 guidance document of the World Health Organization (WHO, 1982) suggested use of loose-fitting, cotton, whole-body dosimeters (WBD) to overcome inefficient sample collection. The California Department of Food and Agriculture recognized the limited usefulness of patch dosimeters for determination of ADD in handler, harvester, and indoor pesticide exposure studies (Maddy et al., 1989). Whole-body dosimeters worn outside or inside standard work clothing may be a suitable means to quantitatively collect... 

The WBDs retained an average potential dermal exposure (PDE) of 13,757 pg chlorpyrifos. If clothing penetration is assumed to be 10% and dermal absorption 9.6% per 24 hr, then the absorbed dose would be 132 pg, and the absorbed dosage would be about 1.9 pg/kg. Biological monitoring of the 13 volunteers wearing cotton dosimeters indicated that the absorbed daily dose that penetrated the WBD and was absorbed was 2 pg chlorpyrifos equivalents/kg (Table 2). 

The shuffle technique consists of placing a cloth dosimeter onto the bottom of two separate platforms that are slightly bigger than a human foot. A platform... 

The other popular technique in use today is the drag-sled technique, which consists of attaching a cloth dosimeter onto the bottom of a square block of some material (such as aluminum) of a predetermined size which has a weight added to the top side. The weighted sled is then pulled one time over a prescribed area of treated turf. The cloth dosimeter is taken off the sled, extracted, and analyzed for residues. 

The cloth dosimeter from the California roller technique consisted of placing a 15.2-cm x 61.0-cm piece of cotton cloth on treated turf, covering the cloth with plastic, and rolling over it with a 25-lb roller. The cloth was then placed in a sample container, which was put in a cooler and transported to the laboratory. The dosimeter was then extracted with hexane. An aliquot of... 

Figure 3 Control chromatogram from cloth dosimeter.

With respect to worker safety and re-entry studies, reference substances are necessary to assay the test substance (and, if applicable, any control substance) and determine its stability and for the analyses of specimens collected in the study. Specimens may include plant material (dislodgeable residues), adsorbent media (inhalation), or clothing/dosimeter materials collected during a worker safety study to assess exposure. If biomonitoring is involved, blood and/or urine specimens may be analyzed against reference substances of known purity. 

Outside dosimeters are on the outside of the outermost layer of clothing, in order to represent exposures resulting from contact of bare skin with the treated foliage. 

Dosimeters under normal clothing are placed in contact with skin (e.g. for forearms) or are outside of the undergarments but under normal clothing (e.g. for chest/back locations). 

Dosimeters under protective clothing represent those that are worn between normal clothing and protective clothing (e.g. protective coveralls) or under protective clothing but in contact with skin (as in the case of a forearm dosimeter for a worker wearing a short-sleeve shirt and protective coveralls). 

Dosimeters under normal and protective clothing represent dosimeters under both layers of clothing when protective clothing is worn over normal clothing. 

A. Thermoluminescent dosimeter (TLD) badges used to provide a permanent record of the cumulative exposure to the whole body must be worn on the trunk (below the shoulders and above the hips) outside of clothing on the portion or area of the body nearest the radiation source. The dosimeter window must face out from the body. 

Once the HazMat team has identified the powder as radioactive, put on Level C attire with a radiation dosimeter. The main danger is inhaling any of the powder. Because nobody is injured, do not enter the scene but instead position yourself upwind and use a loudspeaker to direct aU the victims to the decontamination area. The patients should be decontaminated by having them remove their clothes and personal effects and shower with soap and water. 

Demonstrations and practical exercises in the use of survey meters, self-reading pocket dosimeters, and anti-contamination clothing. 

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