Suction Hazards
The Consumer Product Safety Commission (CPSC) recognizes the main four types of suction entrapment listed here. These main four hazards are the reasoning behind VGB 2008. To understand these hazards will help you understand the purpose of the new law. Drainsafe® recognizes two additional suction entrapment hazards. CPSC has not defined Mechanical Inflation or Chemical Degradation at this point. In our drive for recognition of all types of child suction entrapment we will provide a non-CPSC definition. Updated with the CSPC definitions at the bottom.
Hair Entrapment
One of the five types of Suction Entrapment. When hair strands are drawn through train gratings, hair entanglement may proceed by the knotting or wrapping around elements.
Causes
Typically, these incidents involve individuals of younger ages with long, fine hair, who are underwater with their head near a suction outlet (drain). The water flow into the drain sweeps the hair into and around the drain cover. The hair becomes entangled in and around holes and elements on either side of the cover. Entrapment occurs because the turbulence created under the cover/grate causes the tangling of hair and not necessarily because of strong suction forces. Although the suction forces or current initially draw the hair into the drain cover.
Prevention
The most effective way to prevent hair entanglement is to educate our children to stay away from all suction outlets regardless of cover type or grating configuration. Hair Entanglement is an ever present hazard involving all suction outlets.
The key to suction safety is Layers of Protection. Should one layer fail, there is a additional layer of protection in place to assist in the avoidance of injury and preservation of life.
- Education – Knowing about this hazard and educating our families is the first step to preventing an incident.
- Sound Hydraulics – Multiple Suction outlet configurations, if constructed properly is a safety measure in of itself. If incorrectly installed or used with small diameter plumbing, hydraulic issues could create additional hazards for entrapment.
Limb Entrapment/ Mechanical Inflation
One of the five types of Suction Entrapment. Limb Entrapment is defined as entrapment caused by a limb becoming lodged in an unprotected suction outlet port or unprotected pipe.
Mechanical Inflation could be one of the effects of a limb entrapment.
Causes
The most common cause for this type entrapment is an unprotected Suction Outlet.
Note: Any unprotected opening has the potential for Limb Entrapment.
What separates Mechanical Inflation from limb entrapment is the nature of the force holding the limb to the suction outlet. When a limb becomes entrapped the limb could engorge due to higher pressure inside of the limb then externally, causing the affected limb to swell. With the system vacuum released, mechanical inflation can keep the affected area held firm therefore causing entrapment.
Prevention
The key to suction safety is Layers of Protection. Should one layer fail, there is a additional layer of protection in place to assist in the avoidance of injury and preservation of life.
- Education – Knowing about this hazard and educating our families is the first step to preventing an incident.
- Sound Hydraulics – Multiple Suction outlet configurations, if constructed properly is a safety measure in of itself. If incorrectly installed or used with small diameter plumbing, hydraulic issues could create additional hazards for entrapment.
- Anti-Entrapment Suction Outlet Cover – Use ASME/ANSI A112.19.8b 2008 Certified suction outlet cover on all suction outlets.
- “Plan B” – Should the Anti-Entrapment Suction Outlet Cover fail (Vandalism, Removal, Improper installation) a Plan B should be in place. These are products which activate when a Body Entrapment type situation occurs. These products include Gravity Feed, Vent to Atmosphere, Safety Vacuum Limiting System, or A112.19.17 VGB Compliant Safety Vacuum Release System.
CPSC Definition: Hair Entrapment/Entanglement
CPSC is aware of 43 incidents of hair entrapment or entanglement in pools, spas, and hot tubs between January 1990 and August 2004. Twelve of the incidents resulted in drowning deaths, as a result of hair becoming entangled in the drain grates. Thirty-eight incidents occurred in spas, including hot tubs, and five occurred in a pool. The victims’ ages were between 4 and 42, with a median age of 9 years – 92.5% were under the age of 15 (Ref. 1).
Typically, these incidents involve females with long, fine hair, who are underwater with their head near a suction outlet (drain). The water flow into the drain sweeps the hair into and around the drain cover, and the hair becomes entangled in and around holes and protrusions on both sides of the cover. Entrapment occurs because of the tangling and not necessarily because of strong suction forces, although the suction forces initially draw the hair into the drain cover.
Since about 1982, industry voluntary standards for pools, spas, and hot tubs require drain 5 covers to be certified. The certification includes a maximum flow rate, in gallons per minute (GPM), which should never be exceeded, as this increases the possibility for hair entrapment/entanglement. The design of a drain cover in association with the flow rate through it has been found to relate to the cover’s ability to entrap hair. Large openings in the covers in combination with high flow rates can pull hair through the cover and cause entanglement in the turbulence behind the cover. Reduced flow rates and smaller holes in the drain cover can make entanglement less likely to occur. However, it can be difficult to determine actual flow rates in pools and custom-built spas, and thus to know if they are equipped with the proper fitting to prevent hair entanglement. Drain covers available on the market since 1982 are supposed to conform to a standard that provides hair entrapment/entanglement protection.
CPSC Definition: Other/Unknown Cases
The CPSC is aware of 11 other cases of drain entrapment occurring between January 1990 and August 2004; two of these cases resulted in death. In nine cases, the particular body part or object caught in the drain is unknown. There are two reports of drain entrapment where something being worn by the person became caught, neither resulted in death. In one case, a 43-year-old woman’s necklace became caught. The other case involved a 21-year-old man’s swim trunks.
“Limb Entrapment” – http://www.drainsafe.com/limbentrapment.html
“Retrofit Existing Facilities” – http://www.drainsafe.com/retrofit.html
“CPSC Layers of Protection” – http://www.cpsc.gov/cpscpub/pubs/5101.pdf
“Guidelines for Entrapment Hazards” – http://www.cpsc.gov/CPSCPUB/PUBS/363.pdf