Concern: River Hill High School: February 1st, 2023 (CXRHHS2023000273)

Location
Front Office/Staff Copier Room
Date of IEQ Report Form
Date of Report
Concern
A teacher brought a concern to me about the air quality of our front office and teacher copier room due to frequency of use of the copier machines and lack of air circulation. Concern is related to particulate matter emitted by copying machines, especially if the copying machines are exceed recommended cycle limits. He shared he believes the air quality may be low and may impact the health of our secretarial staff who sit in that area throughout the day.
IEQ Investigation Process

Identify deficiencies that may impact IEQ and/or sources of odor concerns. Typically includes the following depending on the nature of concern, but not limited to:

  • interview/questionnaire of concern individual(s)
  • inspection above drop ceiling (condition of roof deck, pipe insulation, return air plenum)
  • inspection of ventilation system (operation of variable air volume box and outdoor air dampers, check controls, measurements of carbon dioxide, temperature and relative humidity, sources near outdoor air intake, measure return and supply air volume, cleanliness of coils, liner and condensate pan)
  • inspection of exterior
  • inspection below drop ceiling (housekeeping, sink and floor drain traps, signs of past and present moisture concern via visual and/or moisture meter, mold growth, ensure connection of current and capping of abandoned sanitary vents, odorizers, excessive plants and fabric items, identify potential pathways, and measure volatile organic compounds, carbon monoxide, and lighting)
Findings

Date(s) of Assessment: February 14, 2023

Preliminary Research

The school reported the copy room contains two copy machines, both manufactured by Sharp, Model #MX-M7570.

According to manufacturer specifications, the maximum monthly volume for the unit is 400,000. 

Safety Data Sheets (SDS') for the reprographic agents (Black Toner, Product ID #MX-754NT and Black Developer, Product ID#MX-754NV) were provided by Print Services (coordinated the install of the machines system-wide).

The toner and the developer are not classified as hazardous. Personal Protective Equipment (PPE) such as eye, hand, skin, and/or respirator protection is not required under the intended use of this product. Both materials contain carbon black.

Field Assessment

The space consists of two copy machines. One copy machine (Copier #1) is located near the door that leads to the main administrative office and the other (Copier #2) is directly opposite the aforementioned door.

During the visit, it was unclear as to which individual had a concern with their proximity to the copy room. 

The temperature (71.3 degrees Fahrenheit), carbon dioxide (669 parts per million (ppm)), and carbon monoxide (0.0 ppm) were acceptable. 

The space is ventilated via Air Handling Unit-11. The space consists of two supply diffusers and two return vents. Each of these is located in the ceiling and appear at a sufficient distance from one-another to prevent supply air from being directly entrained into the return (i.e. short circuiting).

Copier #2 is located directly beneath one of the return vents, which is an optimum location.

No odors that may be associated with Volatile Organic Compounds (VOCs) or ozone were present in the copy room or the adjoining administrative office. 

Various areas around the copiers were assessed for black dust/particulate using a flash light. No black dust was observed. De minimis general house dust (white/grey) was observed on both copiers.

No visible emissions were observed during the assessment.

Smoke testing was performed at each of the copy room doors. During the time of the assessment, the copy room was under negative pressure. This means that air from the adjoining spaces (main office, attendance office, main hallway, etc.) is "pulled" into the copy room and not vice versa. This is ideal as in general, by-products created through the use of the office equipment (which is expected) would not migrate to other areas of the building, to include the Administrative Office as noted in the concern. 

The supply diffusers were assessed to determine the volume of air supplied to the space. In total, the space receives approximately 545 cubic feet per minute  (cfm) of supply air. Given the room volume, this equates to approximately seven air changes an hour, which is adequate. 

Real-time sampling for Volatile Organic Compounds (VOCs) was conducted in the space to include at occupant level during copy machine use. No VOCs were detected (ppm level) at any time during the assessment.

Particulate Matter

Particulate matter “is a complex mixture of extremely small particles and liquid droplets that get into the air. The data collected does not distinguish between types of particles in the air which can include pollen, skin cells, soil, human/animal hairs, etc. Particles designated as “respirable” are less than 10 micrometers (µm) in diameter and typically fall into two categories, coarse and fine particles. Coarse particles are those that are less than 10 um (PM10) and fine particles are those less than 2.5 µm (PM2.5).  ANSI/ASHRAE standard 62.1-2016 suggests target indoor concentration for PM2.5 and PM10 of 12 and 50 µg/m3 respectively.

Particulate matter data was collected with a TSI AeroTrak Particle Counter (Model #9306-V2). Note that the particle counter is not capable of collecting PM2.5 data. Due to this limitation, PM3.0 data is used. This would provide a more conservative, overestimate of PM2.5.

Particulate samples were collected in 5 locations in the office, during and/or immediately after copies were being made. PM3.0 concentrations averaged 3.2 µg/m3 for the copy room. PM10 concentrations averaged 36 µg/m3 for the copy room. Samples were also collected in the main office (near the door to copy room) and in the attendance office (on desk). Concentrations in these areas were also below the target indoor air concentrations. 

Other Information

Carbon Black

Carbon black makes up a portion of the toner (5-10%) and developer (0.1-1%). According to the SDS sheets reviewed regarding chronic (long-term) inhalation health effects for carbon black, no pulmonary change was reported in the lowest exposure group, which is the most relevant to human exposures. Additionally, the PEL for Carbon Black is 3.5 mg/m3 (3,500 µg/m3). Based on the particulate screening that was performed, there were no visible emissions, and surficial black dust was not observed, Carbon Black does not appear to represent a concern. 

Ozone

Ozone is as a by-product of copy machine use. The manufacture provided emission rate data for ozone. The general dilution rate needed to maintain concentrations of these constituents below one-tenth of the Occupational Safety and Health Administration's (OSHA) Permissible Exposure Limit (PEL) was calculated and is approximately one air change per hour. The space receives approximately seven air changes per hour. 

Volatile Organic Compounds (VOCs)

Various VOCs could be emitted as a by-product of the copy machines. No VOCs were detected at the ppm level during the field assessment. Additionally, the manufacture provided emission rate data for two VOCs. The general dilution rate needed to maintain concentrations of these constituents below one-tenth the OSHA PEL was calculated and was considerably less that one air change per hour. The space receives approximately seven air changes per hour. 

Conclusion

Based on the information above, the Office of the Environment does not believe the copy machines to have a negative impact on air quality within the copy room or the adjoining spaces to include the main administrative area and attendance office. 

Corrective Actions
February 23rd, 2023

Custodial Staff are to continue to maintain the area under the Custodial dusting schedule. 

Closed
Yes
Tracking Number
CXRHHS2023000273