Facial Characteristics Limitation

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.