One of the original design points of the Amron Oxygen Treatment Hood was to place the supply and exhaust connections in front of the patients face to reduce internal noise levels. Although we achieved a significant reduction when compared to other hood designs, there is always room for improvement. For years, some clinical hyperbaric facilities have placed sterile gauze inside the supply hose as a simple means of reducing the ambient noise level within the hood. While some have reported improvement with this practice, we believe it's cumbersome, may increase back pressure and possibly cause the supply hose to disconnect. Using loose gauze also requires additional setup time and may not achieve consistent results.
Amron's hood silencer/filter performs an outstanding job of reducing the incoming noise within an oxygen treatment hood. The large surface area of the filter media does not restrict gas flow and is designed and inexpensive enough for single patient use. Since it already has standard 22mm connections, it can be connected inline or with an elbow (P/N 1641) to accommodate any hood or supply hose setup. Our in-house testing found the silencer to reduce incoming sound levels by 12 to 18dB (this equates to a 94-98% noise reduction), when using flow rates of 30, 40 and 50 LPM. We actually found that the higher the flow rate, the greater dB noise reduction.