Indoor Air Quality Investigation Final Report
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INDOOR AIR QUALITY INVESTIGATION FINAL REPORT For: Vicksburg Community Schools 301 South Kalamazoo Street PO Box. 158 Vicksburg, Michigan 49097 At: Sunset Lake Elementary School 201 North Boulevard Street Vicksburg, Michigan 49097 By: Nova Environmental, Inc. 5300 Plymouth Rd. Ann Arbor, Michigan 48105 January 31, 2019 INTRODUCTION/BACKGROUND On January 24, 2019, Ms. Nancy Spicketts of Vicksburg Community Schools contacted Nova Environmental, Inc. with a request to conduct an Indoor Air Quality (IAQ) investigation at the Sunset Lake Elementary School, located at 201 North Boulevard Street, Vicksburg, Michigan. Ms. Spicketts indicated that there a staff member experiencing health concerns and requested an investigation of Classroom 410. Based on the information provided by Ms. Spicketts, it was decided that the Indoor Air Quality (IAQ) Investigation would include an on-site evaluation, basic parameter air quality measurements, airborne fungal spore testing and comprehensive volatile organic compound (VOC) testing in Classroom 410. An environmental consultant from Nova Environmental, Inc. arrive on-site and performed the investigation on January 31, 2019. METHODS Nova Environmental, Inc. conducted limited indoor air quality-monitoring activities at the Sunset Lake Elementary School. The investigation included the following: • A visual inspection for any obvious indoor pollutant sources in area of specific concern, (Room 410); • General Parameter measurements including; temperature, humidity, carbon dioxide, carbon monoxide, hydrogen sulfide, percent oxygen, hydrocarbons, chlorine, and nitrogen dioxide. • Air sampling in order to determine airborne concentrations of mold and fungal spores in representative locations within the building. • TO-15 sampling for VOCs INVESTIGATION SUMMARY This section is intended to provide a general summary of the results of this IAQ Investigation. There are a number of observations and recommendations that are made and provided later within this Report. Although no “smoking gun” was identified that would be a single source cause of the symptoms that had been described to the Nova representative, there are several issues that were discovered that could impact the air quality within Classroom 410 and Sunset Elementary School as a whole. Based on the results of the mold spore air sampling (and the fact that no visible signs of mold were identified), it does not appear that mold is of concern within Room 410 at this time. Based on the results of the TO-15 VOC sampling, it does not appear that VOCs are a concern within Room 410 at this time. AIR MONITORING RESULTS Temperature and Relative Humidity Thermal parameters of an environment, although basic in nature, should not be overlooked, as certain temperature/humidity level combinations can affect human comfort. Temperature and relative humidity in certain combinations can create hot and moist environments conducive to fungus/mold growth, or cold and dry environments that increase human discomfort. Nova Environmental, Inc. conducted temperature and relative humidity measurements in order to gather the following information during the visit: 1. Information which may be used to evaluate the general performance of the HVAC system. 2. Identify possible temperature and humidity conditions and/or combinations that may promote the growth of mold and fungi or contribute to human discomfort. Temperature and relative humidity readings were collected in Classroom 410 and the hall outside Classroom 410. The temperature readings ranged from 67.5°F to 70.4°F. The relative humidity levels ranged from 8.2% to 11.8%. Complete temperature and relative humidity data collected during the IAQ Investigation is located in Appendix A. It should be noted that these measurements were taken on a non- school day so do not represent measurements during occupied times. According to industry comfort levels, the temperature ranges in the facility on the day of the investigation feels most comfortable when the relative humidity ranges between 30% and 60%. As the data in Appendix A indicates, the relative humidity measurements in areas sampled were well below the recommended relative humidity ranges for the temperatures measured. This was due to the extremely low relative humidity and low temperatures on the outside of the building. These measurements are unlikely to be conducive to mold/mildew growth or represent a potential health concern at this time. Carbon Dioxide Carbon Dioxide (CO ) is an important parameter in assessing indoor air quality, as above-normal concentrations can provide an indication of inadequate ventilation. Since CO is expired by humans during respiration, the level of₂ CO indoors as compared to outdoors may be used in determining the amount of fresh outside air that is included in the total ventilation process as well as a₂ general indication as to the efficiency of the HVAC system.₂ Areas with CO levels that exceed 700 ppm above the outdoor ambient level could distract from occupant comfort and can be considered to possibly be an area with inadequate ventilation. This does not mean that areas with CO₂ levels in excess of this range are considered hazardous or a health-related issue, but rather these levels should be used as a guideline to help maximize comfort for all occupants. Government regulatory agencies and₂ occupational health professional organizations have established levels of carbon dioxide that the average worker may be exposed to on a regular basis (the typical 40 hour work week) without any adverse effects. These levels range from 5,000 ppm (parts per million) to 10,000 ppm. The measured CO levels on the day of the investigation ranged from 410 ppm to 487 ppm (outside CO levels was 371 ppm). Variables potentially effecting the carbon dioxide levels such as whether windows or doors were open₂ or closed and whether the ventilation was on or off were also note during monitoring. ₂ The carbon dioxide levels were within expected ranges and were well below OSHA/MIOSHA enforceable limits of 5,000 ppm and 10,000 ppm respectively. Complete carbon dioxide data recorded during the investigation is shown in Appendix A. Carbon Monoxide Carbon monoxide (CO) is a by-product formed by incomplete combustion of a variety of flammable materials. Indoor sources can result from malfunctions of the heating, ventilation and air conditioning (HVAC) system, fossil-fueled hot water heaters or outside contaminants being drawn into the building through the HVAC system. Several governmental agencies and professional organizations have established levels to assess/regulate exposure, typically in a manufacturing/industrial environment. These levels range between 25 ppm and 50 ppm based on an eight-hour time weighted average. Low or no detectable levels of carbon monoxide were recorded during this investigation and are unlikely to be a concern at this time (see Appendix A). Hydrogen Sulfide Hydrogen sulfide, (H2S) is a sulfur-based compound with a smell similar to that of “rotten eggs.” Hydrogen sulfide is frequently associated with sewer gas. H ₂S measuremen less than the instrument detection limit and are unlikely to represent a potential health concern at this time. Nitrogen Dioxide The most prominent sources of Nitrogen Dioxide (NO2) are internal combustion engines burning fossil fuels. Outdoors, NO2 can be a result of traffic from motor vehicles. The levels of the areas sampled were all less than the instrument detection limit and unlikely to represent a health concern at this time. Hydrocarbons Hydrocarbons, (HC) are organic compounds frequently associated with the incomplete combustion of natural gas and/or other fossil fuels. Hydrocarbon measurements were collected in part to ensure proper operation of the facility’s HVAC systems. Hydrocarbon measurements were recorded as a percentage of the Lower Explosive Limit (LEL). The LEL is an airborne hydrocarbon level, which represents the percent explosiveness or flammability of airborne hydrocarbons. The Occupational Safety and Health Administration (OSHA) has established 10% of the LEL as a level to which building occupants or employees may be exposed with minimal risk. During the investigation, HC measurements were less than the instrument detection limit. Hydrocarbons are unlikely to represent a potential health concern at this time. Percent Oxygen Oxygen is a colorless, odorless, naturally occurring gaseous element essential to life processes and combustion. In ambient atmospheres, oxygen generally represents 21% of air. Nitrogen represents the other major component of ambient air (79%). Generally established governmental guidelines have determined percent oxygen levels in air that are acceptable for human exposure. These guidelines establish a range of oxygen in the air to which to humans may be exposed without the need of respiratory protection and/or a supplemental oxygen source. These range from 19.5% to 23.5%. All of the oxygen levels recorded during this investigation were within the established guidelines. AIRBORNE FUNGAL SPORE SAMPLING Bioaerosols are defined as materials that have been finely divided and suspending in the air (aerosol) that a biological origin or activity (bio-). Ore simply, these are living or dead bacteria, mold and fungi or the spores of mold and fungi. Individuals may react to the entire bacteria, mold and fungi or its spores, or react to mycotoxins, the chemicals that the fungi produce as a by-product of their metabolism. These “biological particles” and mycotoxins can affect different