NIOSH says study of Great Wolf Lodge inconclusive

Posted by Trina Kinstler - email

MASON, OH (FOX19) -- The National Institute for Occupational Safety and Health (NIOSH) has released a report on the Great Wolf Lodge (GWL) after over 600 people reported symptoms of coughing, eye and nose irritation, respitory irritation and skin rashes from late 2006 through early 2007.

Employees at the lodge also reported symptoms. NIOSH says inspections conducted in the facility in response to these complaints revealed that GWL was in compliance with all Ohio Department of Health and Ohio Department of Agriculture Rules regarding the public swimming pools and water features and they exceeded compliance with the Ohio Basic Building Code with their ventilation system.

NIOSH says Great Wolf Lodge cooperated fully in the investigation, increased their ventilation by 10%, brought in a nationally recognized ventilation expert to evaluate their system to insure it was performing as designed, conducted air sampling and water testing far in excess of any existing standards, and began an education program for their bathers to minimize the formation of chloramines in the water park.

NIOSH's conclusion regarding employee exposure, who would have had long-term exposure compared to the short-term exposure experienced by any visitors to the water park, is that their review of the ventilation system, relative humidity and trichloramine measurements, the ventilation system at the time of their evaluation may not have been providing adequate capture and removal of chloramines at the pool surface and deck levels.  Additionally, trichloramine concentrations measured were similar to levels found in other indoor swimming pool studies and some were at levels reported to cause irritation symptoms.  Trichloramines are a naturally occurring byproduct in chlorinated pools.  NIOSH's report also provides some recommendations to prevent these types of problems, most of which Great Wolf Lodge has already implemented.

Some of the symptoms can also be attributed to placing 3000 people in a close, warm, and humid environment during cold and flu season.

NIOSH believes that some of the problems reported by bathers at that time can be attributed to elevated levels of chloramines during high bather load periods causing short term discomfort to less than 1% of the total bathers using the Great Wolf Lodge Water Park.  Some people are more sensitive to chlorine and chloramine exposure  There is no exposure standard for chloramines and the result of the testing completed by NIOSH indicated that some of the levels were in the range that other bathers in other indoor swimming pool environment's had experienced mucous membrane irritation.  Some of the skin rashes can be attributed to long-term exposure to the chlorine in the pool as many bathers were in the water for extended periods of time.