Safety - Field Sampling: Principles and Practices in Environmental Analysis - page 95

Protective glasses or goggles must have shatterproof lenses. They must protect the eyes
not only from the front but also from the sides, bottom, and top. It is surprising how often
liquids and solids can splash and bounce around in such a way that they enter the area of
the eyes from the side, top, or bottom. Workers should be encouraged to maintain their
goggles, which means keeping them clean and sanitary at all times. Dirty lenses do
obstruct vision, and dirty sides may induce irritation and dermatitis. Cleanliness is a must
for the productive use of safety goggles.
4.6.3. Face Masks and Respirators
Whether in enclosed areas or open fields, very dusty situations call for the use of simple
filtering dust masks. These are made of paper and cover the nose and mouth. Dust masks
are designed to simply filter dust particles out of the breathing air; they must not be used
in situations in which gases or fumes are present because they will not protect personnel
from these dangers.
In some situations the nose and respiration system must be protected from toxic,
overpowering, or otherwise hazardous gases. In these cases a respirator, which can come
in two forms, is required. One covers just the nose and mouth and is called a half mask
respirator. (See Figure 4.4.) The other covers both eyes, the nose, and the mouth and is
called a full face mask. Both types come with a variety of filters suitable for different
situations. There are filters for organic vapors, acid vapors, ammonia and amines, dust,
and various combinations of these. In all cases it is essential that they be adjusted to fit
properly. They must also be checked for leaks before they can be effective in protecting
the wearer.
In agricultural sampling respirators should always be readily available. Anhydrous
ammonia, which is a gas at standard temperature and pressure