The document discusses recommendations for operating flammable gas instruments in enclosed areas and guidelines for open sumps in ventilated areas. Figures 56 and 57 provide visuals, with Figure 56 showing flammable gas instruments operating in an inadequately ventilated enclosed area and Figure 57 depicting an open sump in a ventilated, non-enclosed area.

1. 88 API RECOMMENDED PRACTICE 505
Figure 56—Flammable Gas–operated Instruments in an Inadequately Ventilated
Enclosed Area
(See 10.11.3.4)
Figure 57—Open Sump in Non-enclosed, Adequately Ventilated Area
(See 9.2.3, 10.12.2, 10.12.3, and 10.13.2c)