Where X-ray protection plaster
is applied X-ray barrier barite plaster is used in hospitals, research centers, in production - where there are sources of X-ray radiation. In hospitals, these are tomographs and X-ray machines, in research centers - various experimental installations, etc. The composition of barite plaster includes barite concentrate or barite sand , capable of stopping penetrating radiation.
Two main solutions are used in finishing such premises: sheet lead and barite plaster. Sheet lead is a scarce and expensive material, so X-ray plaster is much more common;their various combinations are also used. According to the protective properties of the millimeter layer of lead corresponds to 20-25 mm of barite plaster.
How barite plaster
is prepared Barite plaster is usually prepared on the basis of a cement-sand mortar. As a plasticizer, cement with PVA glue is used, as a filler - actually barite sand. The mixture is diluted with water to the desired consistency( the water-cement ratio should not exceed 1: 4) and is sent to work.
Barite sand is ground mined barite with a grain size of not more than 1.25 mm .In addition to sand, barite dust is used, that is, heavy spar, ground to a pulverized state. Regardless of the type of aggregate, the content of barite in the plaster should not be below 85% - this is a fundamentally important issue for the safety of people.
Portland cement and slag Portland cement of not less than 300 are suitable for the preparation of barite plaster. The cement content in the plaster depends on the features of the specific room and the design radiation power, the thickness of the protective layer depends on this. In case the required thickness exceeds 5 cm, barite concrete slabs are used instead of plaster.
Features of barite plaster that are worth remembering
Here are some features that should be kept in mind when working with barite plaster:
- The required thickness of barite plaster starts from 3 cm for walls and floor and from 5 mm for the ceiling. The plaster must be applied from both sides of the wall.
- All work on the application of X-ray plaster should be carried out at an air temperature of at least 15 ° C with high humidity. The same conditions will have to be maintained for at least two weeks after the end of the work.
- On wooden walls it is necessary to put a layer of plaster, increased by centimeter and more .
- Barite plaster is applied only by hand and only by separate layers in a thickness of half a centimeter.
Calculate the amount of barite concentrate necessary for plastering all surfaces is not difficult. We must proceed from the fact that a centimeter layer of plaster covering one square meter of surface will have to spend 20 kg.barite. The amount is, of course, considerable - but it is not necessary to save on safety and health, besides barite sand is cheap enough in production and costs not so much. Barite plaster is a very economical and at the same time equally effective replacement for lead sheets.
