How do you not know how deadly the fumes from a manure pit are? Granted many of the fumes produced do not have an odor but one would think if you run a livestock farm you would know ventilation of a manure pit is a must. Doesn't say what type of pump they were fixing but if it was equipment for ventilating the fumes I would think that would require respirators. Maybe a monitor to alert you before you pass out.
Geezzzzz