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Suction Entrapment in Hotel Swimming Pools

Background

In June of 2002, 7-year old Virginia Graeme Baker drowned when she became stuck to the suction drain outlet of a hot tub.  Baker, who had been swimming without assistance since age 3, was trapped underwater against the drain by the suction force of the water flowing into the drain.  She was unable to free herself.  It took two men to pull her free, and the drain cover broke from the force of removing her.

Most permanent swimming pools and spas are equipped with suction outlets (drains) which, in conjunction with pumps, permit the filtration, heating, chemical treatment, and/or draining of water.  Incidents like Virginia Graeme Baker’s illustrate that, without certain design features or equipment, suction drain outlets can entrap a swimmer beneath the water.

On December 19, 2007, President George W. Bush signed into law the Virginia Graeme Baker Swimming Pool and Spa Safety Act (VGB Act).  The act specified that a new swimming pool and spa drain cover standard was to be treated as a consumer product safety rule.  Effective one (1) year following the enactment of the law, “…each swimming pool or spa drain cover manufactured, distributed, or entered into commerce in the United States shall conform to the entrapment protection standards of the ASME/ANSI A112.19.8 performance standard, or any successor standard regulating such swimming pool or drain cover.”  The law further required that, effective 1 year following enactment, every pre-existing and new public swimming pool was to be equipped with anti-entrapment systems that complied with the ASME/ANSI A112.19.8 standard.  The law defined public pools to include those pools open to the patrons of a hotel.

Therefore, starting on December 19, 2008, every pre-existing and all new hotel swimming pools in the United States were required to be equipped with compliant anti-entrapment devices and systems

On May 26, 2011, the Consumer Product Safety Commission (CPSC) issued a recall of several presumably VGB Act compliant drain covers that were found to be incorrectly rated to handle the flow of water through the cover.  The recall affected 8 manufactures and an estimated 1 million drain covers throughout the United States.

In July, 2011, the Consumer Product Safety Commission voted unanimously to approve ANSI/APSP-16 2011 (APSP is the Association of Pool and Spa Professionals) as the successor standard to the ASME/ANSI A112.19.8.

Existing Pools

All submerged suction outlets at existing hotel pools should have been fully compliant with the VGB Act by December 19, 2008.  Several manufactures produce drain cover outlets that are intended for use at existing pools.  However, for out-of-the box use of the covers, specific manufacturer requirements regarding flow rates, wall or floor location, sump dimensions, etc. must be strictly observed in order for the drain to be compliant.  Often, in order to meet the manufacturer’s requirements, the drain sumps and outlets at existing pools were demolished and reconstructed.  The ASME/ANSI standard and the subsequent ANSI/APSP-16 also allow for field-fabricated outlets to be designed, and tested in place, by a registered design professional (an engineer or, in some instances, an architect).  The design of field-fabricated outlets is required to address cover/grate loadings, durability, hair/finger/limb entrapment issues, cover/grate secondary layer of protection, related sump design, and features particular to the site.

The VGB Act requires that any swimming pool with a single main drain outlet should be provided with an “unblockable” drain, or one of 6 other secondary systems for entrapment protection, including: a safety vacuum release system (SVRS), a suction-limiting vent system, a gravity drainage system with a collector tank, an automatic pump-shutoff system, drain disablement, or any other system determined by the Commission to be equally effective.  Please note that many manufacturers and many jurisdictions require that SVRS devices be tested on a regular basis.  For example, the Florida Department of Health requires that the SVRS device be tested at a minimum of once a month.

Every hotel swimming pool facility should have on file the certificates regarding the drain outlets, including the date the drain cover was placed in service.  These certificates are required by the ASME/ANSI and the ANSI/APSP standard and should have been provided by either the manufacturer or the registered design professional responsible for the outlets.  Each facility should also maintain records of testing of secondary protection devices.

All compliant drain covers have been evaluated and marked with the service life of the cover.  Most manufactures certify their covers for a useful life of either 5 or 7 years, after which, the durability of the drain cover is no longer guaranteed.  Covers installed in 2008 when the VGB Act was first enacted, have exceeded, or are close to exceeding, their expected life and should be replaced.

It is important for facilities to maintain awareness of the entire swimming pool system. Changes to any part of the system, including pumps, filters, heaters, etc. can affect the flow rates of the system, thereby changing the suction characteristics of the drain outlets.  These changes can create non-compliance with the certificates previously issued for the drain outlets.

If there is any doubt about whether a facility is in compliance with the VGB Act, a registered design professional should be retained to investigate the facility and determine its compliance.  Direct testing can be performed at operating swimming pools using scuba equipment, body simulating devices, and force meters to determine the exact suction forces at drain outlets to assess whether or not they comply with the VGB Act.  Oftentimes, there are systems or retrofits that can be applied, even to fully VGB compliant pools, which will further reduce the risk of suction entrapment.

New Construction

In conjunction with 2012 releases of the International Codes, the first edition of the International Swimming Pool and Spa Code(IPSC) was released. The goal of the code committee was to create a code that coordinated and enhanced the provisions previously found in the International Codes and APSP standards to upgrade pool and spa safety and to meet the requirements of the VGB Act.  The IPSC is fully compatible with the International Codes and provides a reference standard to assist with swimming pool design and construction that complies with the applicable electrical, mechanical, and plumbing codes.  Many jurisdictions have already adopted the IPSC, and its adoption is anticipated to be widespread, coinciding with adoption of the International Codes.  As part of the 2012 IPSC, the ANSI/APSP-7 2006 American National Standard for Suction Entrapment Avoidance in Swimming Pools, Wading Pools. Spas, Hot Tubs, and Catch Basins (APSP-7) is codified.

Not all jurisdictions require submerged drain outlets at swimming pools.  Careful consideration should be given during pool design to utilizing circulation methods that do not incorporate any submerged outlets, thereby completely eliminating any suction entrapment risk.  Gravity flow outlets with a collection or “surge” tank can also be incorporated to eliminate direct connection of the swimming pool drains to the pumps (this type of system is required in Florida). This method dramatically reduces entrapment risk.  Where main drain outlets are utilized, they should be unblockable, or installed with no fewer than two interconnected outlets spaced no closer than 3 feet.  The drain outlet system should be designed to handle 100 percent of the maximum system flow, assuming one drain outlet is completely blocked, without exceeding the suction forces allowed by the VGB Act.

The significant code changes and current pace of adoption of new codes by regulatory agencies have created circumstances where pool builders should not be utilizing the stock plans they have used in the past to construct new swimming pools at hotels.  Every facility will have some unique features that should be addressed by registered design professionals.  Construction documents should be prepared for each individual swimming pool that specifically account for the features unique to the facility.  The documents should contain all the information and certificates required for full compliance with the VGB Act and the applicable locally adopted codes.  New hotel facility owners should carefully review the proposed construction plans for the swimming pool, ensuring that a registered design professional has addressed the uniqueness of the facility and provided an engineering seal on the documents.

Careful consideration during the design process easily incorporates compliance with the VGB Act into the initial construction of the pool.  Suction entrapment risk can be significantly reduced, and in some cases, completely eliminated, through proper design by qualified, registered design professionals.

References

  1. Virginia Graeme Baker Swimming Pool and Spa Safety Act of 2007, 14 U.S.C. Sections 1401-1409.
  2. ASME/ANSI A112.19.8 – 2007 Suction Fittings for Use in Swimming Pools, Wading Pools, Spas, and Hot Tubs.
  3. ANSI/APSP-16 2011 American national Standard for Suction Fittings for Use in Swimming Pools, Wading Pools, Spas, and Hot Tubs.
  4. ANSI/APSP-7 2006 American National Standard for Suction Entrapment Avoidance in Swimming Pools, Wading Pools, Spas, Hot Tubs, and Catch Basins.
  5. International Code Council, 2012 International Swimming Pool and Spa Code.
  6. Public Swimming Pools and Bathing Places, Florida Administrative Code 64E-9, Sections 9.001-9.018