John introduces a new positive air pressure attenuator to the American engineering community.
This column has always advocated innovative solutions to design problems, whether likely to achieve instant standards approval or not. In order to move our profession forward, it is essential that we are open to persuasion and willing to accept solutions drawn from, or informed by, other engineering disciplines. The attenuation of positive air pressure transients is one such area.
The prevention of odor ingress from a drainage system carrying waste from sanitary appliances has been the major concern for system designers for over 100 years. While the water trap seal is accepted as the main protective device, these have to be protected to ensure that system design and usage will not generate air pressure transients of sufficient magnitude to lead to trap depletion.