Table 1 – Limitations related to operator’s facial characteristics
Figure 6 – Facial
characteristics affecting the use of a respirator
Limitations of Respiratory Protection
In general, respiratory
protection is the weakest of the Hierarchy of Controls, You should consider
whether you would know if the respiratory protection is failing to protect
before a dangerous dose is inhaled. Irritant gases often self-indicate, so you can smell them or they will sting the eyes at
low concentrations, allowing a quick escape before too much damage is done.
However, many other toxic gases have an odour threshold above the hazardous level. You should consider
whether a higher control method is possible through the use of engineering
controls, ventilation, substitution of the chemicals etc.
Selecting the Exact Make and Model
There
are a wide range of manufacturers and suppliers of respiratory protection. Most
offer a full spectrum of types, and they will offer several manufacturers’
models. As design and fit are all-important, it makes sense for the wearer to
try several alternatives and to choose the one that feels most comfortable.
For some unusual
contaminants, only specialist manufacturers may offer the exact mask or
cartridge for instance when working with Mercury. It is important however that
the qualified expert selects the exact makes and models to be used for each
situation, and that the worker uses exactly that make and model for the job.
