Health Hazard Evaluation Report 2012-0155-3180 Page 1

Evaluation of Environmental Controls at a Homeless 

Shelter (City Rescue Mission–New Life Inn) Associated 

with a Tuberculosis Outbreak – Florida

Report No. 2012-0155-3180

July 2013

Stephen B. Martin, Jr., MS, PE

Kenneth R. Mead, PhD, PE

R. Brent Lawrence, MS, GSP

Michael C. Beaty

U.S. Department of Health and Human Services

Centers for Disease Control and Prevention

National Institute for Occupational Safety and Health
Page 2 Health Hazard Evaluation Report 2012-0155-3180

Contents

Highlights ......................................................... i

Abbreviations ................................................. iv

Summary ...........................................................1

Introduction .................................................... 2 

Background ..................................................... 3

Assessment ...................................................... 3

Results & Discussion ...................................... 4

Conclusions ................................................... 15

Recommendations ...................................... 16

Outline of Future NIOSH Involvement .... 20

References ..................................................... 21

Tables ............................................................. 23

Figures ........................................................... 28

Acknowledgements .................................... 32

The employer is required to post a copy of this report for 30 days at or near the 

workplace(s) of affected employees. The employer must take steps to ensure 

that the posted report is not altered, defaced, or covered by other material.
Health Hazard Evaluation Report 2012-0155-3180 Page i

Highlights of this Evaluation

The National Institute for Occupational Safety and Health received a technical assistance 

request from the Duval County Health Department in Florida. The request asked that we 

assess the heating, ventilation, and air-conditioning systems and make recommendations to 

improve overall environmental controls at City Rescue Mission–New Life Inn, a local homeless shelter with epidemiological links to an ongoing tuberculosis outbreak.

What NIOSH Did

● We visited City Rescue Mission–New Life Inn on August 20, 2012.

● We met with representatives from the Duval County Health Department and City 

Rescue Mission–New Life Inn to discuss the ongoing tuberculosis outbreak.

● We recorded the physical sizes of occupied spaces.

● We measured ventilation air flow into/from occupied spaces.

● We collected information on all shelter air-handling units.

What NIOSH Found

● City Rescue Mission–New Life Inn was working in conjunction with the Duval County 

Health Department to improve administrative controls to identify guests on priority 

screening lists or those with symptoms of tuberculosis.

● Air-handling units were generally in good working order, but some had no filter or 

improper filter configurations installed, and others had condensate leakage.

● No fresh outdoor air was being supplied to the occupied spaces by building mechanical 

systems.

● There was no clearly defined area to separate guests suspected of having tuberculosis 

from the general guest population.

● A written respiratory protection plan did not exist.

● Most bathroom exhaust fans were not functional.

What City Rescue Mission–New Life Inn Should Do

● Continue to work with the Duval County Health Department to improve overall 

administrative controls and help ensure rapid identification of guests suspected to have 

tuberculosis.

● Develop a comprehensive infection control plan with input from the Duval County 

Health Department and Florida Department of Health.

● Modify shelter ventilation systems to provide adequate fresh outdoor air to all occupied 

spaces using a strategy compatible with existing system capacities.

● Strategically reposition supply and exhaust grill locations to improve air flow patterns 

in occupied spaces, particularly in the three large guest sleeping areas.
Page ii Health Hazard Evaluation Report 2012-0155-3180

● Install the highest efficiency air filter possible that is consistent with the proper 

operation of each air-handling unit.

● Modify at least one area of the shelter for use as a respiratory separation area, when 

necessary.

● Develop and implement a written respiratory protection program that meets the 

requirements of the Occupational Safety and Health Administration’s respiratory 

protection standard 29 Code of Federal Regulations 1910.134.

● Repair or replace all bathroom exhaust fans.

● Develop and implement a written operation and maintenance plan for shelter heating, 

ventilation, and air-conditioning systems, to include a filter replacement schedule.
Health Hazard Evaluation Report 2012-0155-3180 Page iii

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Page iv Health Hazard Evaluation Report 2012-0155-3180

Abbreviations

μm Micrometer

AHU(s) Air-handling unit(s)

ACH Air changes per hour

AII Airborne infection isolation

ANSI® American National Standards Institute

ASHRAE® American Society of Heating, Refrigerating and Air-Conditioning Engineers

CDC Centers for Disease Control and Prevention

cfm Cubic feet per minute

CFR Code of Federal Regulations

DCHD Duval County Health Department

DRDS Division of Respiratory Disease Studies

DTBE Division of Tuberculosis Elimination

HEPA High-efficiency particulate air

FGI Facility Guidelines Institute

HVAC Heating, ventilation, and air-conditioning

ICP Infection control plan

MERV Minimum efficiency reporting value

NCHHSTP National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention

NIOSH National Institute for Occupational Safety and Health

O&M Operation and maintenance

OSHA Occupational Safety and Health Administration

RH Relative humidity

TB Tuberculosis

UV Ultraviolet

UVGI Ultraviolet germicidal irradiation 
Health Hazard Evaluation Report 2012-0155-3180 Page v

Mention of any company or product does not constitute endorsement by NIOSH. In 

addition, citations to websites external to NIOSH do not constitute NIOSH endorsement 

of the sponsoring organizations or their programs or products. Furthermore, NIOSH is not 

responsible for the content of these websites. All web addresses referenced in this document 

were accessible as of the publication date of this report.
Health Hazard Evaluation Report 2012-0155-3180 Page 1

Summary

In May 2012, the National Institute for Occupational Safety and Health (NIOSH) received a 

request for technical assistance from the Duval County Health Department as part of its response to an ongoing tuberculosis (TB) outbreak among homeless persons in Florida. The request asked NIOSH to assess heating, ventilation, and air-conditioning (HVAC) systems and 

make recommendations to improve overall environmental controls at four homeless facilities 

with epidemiologic links to past or ongoing TB disease transmission.

During an on-site evaluation of the City Rescue Mission–New Life Inn homeless shelter in 

August 2012, we collected physical and ventilation measurements in all key areas of the 

facility. We focused on areas where shelter 

guests typically congregate or spend significant amounts of time. We recorded the 

make and model number of all air-handling 

units (AHUs) providing supply air to the 

facility, and visually inspected the units. 

When possible, we measured the air flow 

rate through supply diffusers and return 

grilles. 

The ventilation systems in place could have 

contributed to airborne disease transmission 

among shelter guests. With the exception of 

condensate leakage from a few AHUs, the 

units appeared sufficiently maintained to be 

fully operational. Unfortunately, none of 

the AHUs provided fresh outdoor air to the 

occupied spaces, as required by the Florida 

Building Code and the American Society of 

Heating, Refrigerating and Air-Conditioning 

Engineers design standards. In addition 

to alleviating odors and maintaining occupant comfort, outdoor air serves to dilute 

infectious aerosols, such as Mycobacterium 

tuberculosis droplet nuclei that are responsible for TB transmission.

Since the TB outbreak began, City Rescue Mission–New Life Inn has taken numerous steps 

to improve administrative controls, particularly when it comes to identifying guests showing 

signs and symptoms of TB. We recommend additional improvements to the administrative 

and environmental controls at the shelter. From a ventilation standpoint, we suggest that all 

occupied spaces in the shelter are supplied adequate amounts of outdoor air. In addition, we 

identified areas that could be converted for use as respiratory separation areas. These spaces 

could serve to separate guests suspected of having TB or other respiratory diseases from the 

remainder of the guest population, until medical evaluation or treatment could be obtained. 

We also recommend developing a written infection control plan, HVAC operation and mainNIOSH investigators conducted an assessment of environmental controls in the 

City Rescue Mission–New Life 

Inn, a homeless shelter linked 

to an ongoing tuberculosis 

outbreak. The investigation 

revealed problems with the 

existing environmental controls, along with needed improvements in administrative 

controls and respiratory protection. Detailed recommendations are provided in this 

report to improve the shelter 

environment and reduce the 

likelihood of disease transmission.
Page 2 Health Hazard Evaluation Report 2012-0155-3180

tenance plan, and a written respiratory protection program. Having these plans/programs in 

place will help the shelter under normal operating conditions, and especially during future 

outbreaks of respiratory disease.

Introduction

Since 2004, the Duval County Health Department (DCHD), in conjunction with the Florida 

Department of Health and U.S. Centers for Disease Control and Prevention (CDC), has 

linked over 100 cases of active tuberculosis (TB) disease, resulting in 14 deaths, to a cluster 

having matching genotype results (PCR00160 or FL0046) in Duval County, Florida. Roughly half of the cases of active TB disease have been identified since 2010. Of the 100 cases, 

79% had a history of homelessness, incarceration, or substance abuse, with 43% being homeless within one year of diagnosis.

In response to the ongoing outbreak, a team of epidemiologists from the CDC National 

Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Division of 

Tuberculosis Elimination (DTBE) conducted an on-site investigation in February and March 

2012. In their report dated April 5, 2012, the CDC team included a recommendation to 

improve environmental controls at homeless facilities implicated in possible disease transmission. On May 22, 2012, the Division of Respiratory Disease Studies (DRDS), National 

Institute for Occupational Safety and Health (NIOSH), CDC received a request for technical 

assistance concerning the TB outbreak in Duval County. The request was made by a CDC 

Public Health Advisor temporarily assigned to Duval County. The request specifically asked 

NIOSH to evaluate shelters’ heating, ventilation, and air-conditioning (HVAC) systems and 

make recommendations to improve overall environmental controls. The request was initially 

made for an assessment at one homeless shelter. However, in subsequent discussions with 

the TB Program Manager at DCHD, a CDC Public Health Advisor with the Florida Department of Health, and representatives from CDC/NCHHSTP/DTBE, the request was expanded 

to include four facilities that provide assistance to the homeless and which had epidemiologic 

links to past or ongoing TB disease transmission.

In response to the expanded request, a NIOSH team visited the four facilities in August 2012. 

This report describes the measurements and associated findings from our assessment at the 

City Rescue Mission–New Life Inn. It details and prioritizes our recommendations for improving environmental controls at the shelter, and outlines the current plan for future NIOSH 

involvement. 

Keywords: NAICS 624221 (Temporary Shelters), tuberculosis, environmental controls, ventilation, homeless shelter, airborne infection, airborne transmission, respiratory
Health Hazard Evaluation Report 2012-0155-3180 Page 3

Background

Tuberculosis and Homeless Populations

TB is a disease caused by Mycobacterium tuberculosis (M. tuberculosis) bacteria. When a 

person with active TB disease coughs or sneezes, tiny droplets containing M. tuberculosis

may be expelled into the air. Many of these droplets dry, and the resulting residues remain 

suspended in the air for long periods of time as droplet nuclei. If another person inhales 

air that contains the infectious droplet nuclei, transmission from one person to another may 

occur. Homeless people have been identified as a high-risk population for TB infection and 

disease since the early 1900s [Knopf, 1914]. With the increase in homelessness in the United 

States since the 1980s, TB among homeless persons has become a subject of heightened 

interest and concern [CDC 1985; 1992; 2003a,b; 2005a; Barry et al. 1986; Slutkin 1986; McAdam et al. 1990; Nolan 1991].

City Rescue Mission–New Life Inn 

The New Life Inn serves as the “front door” to various programs and services offered by City 

Rescue Mission. It provides sleeping areas for men only, and consists of a main three-story 

brick building with an adjacent single-story brick/stucco annex. Both buildings are equipped 

with central HVAC systems. The first floor of the main building houses a reception area, 

laundry facility, large kitchen, and dining area capable of seating 60-70 guests comfortably. 

The second floor is comprised of staff offices on the northern side while the southern side 

has one barracks-style sleeping area with 24 bunks to house men in the City Rescue Mission work program. There are also three smaller transition rooms, each with 4 bunks, used 

to house work program guests preparing to leave the shelter and transition out on their own. 

The third floor has two large barracks-style sleeping areas with restroom and shower facilities for each. The sleeping area on the north side is equipped with 60 beds (30 bunk beds) for 

men in the initial three months of the City Rescue Mission LifeBuilders program. The south 

sleeping area has 67 beds for use by overnight and emergency services guests. Overnight 

guests may stay at the shelter a maximum of seven days per month, and longer stays are possible if space is available.

In addition to feeding the guests that sleep at the shelter, an additional 100–400 men and 

women eat breakfast and dinner there each day through the Mission’s food program. Between 10–12 staff members work at New Life Inn during the day, and two staff members are 

present each night. The shelter is typically full throughout the year, but the number of overnight guests increases during periods of bad weather. During periods of high occupancy, the 

dining room on the first floor and/or the annex building are used as overflow sleeping areas 

for 100 or more guests.

Assessment 

On August 20, 2012, an opening meeting was held at the Duval County Health Department. 

An update was given on the current status of the ongoing TB outbreak among the homeless 
Page 4 Health Hazard Evaluation Report 2012-0155-3180

population, and we provided background information on NIOSH, the nature of the technical 

assistance request, and the ventilation measurements we planned to collect at each facility. 

Aside from NIOSH and DCHD staff, representatives from New Life Inn and two of the three 

other homeless facilities to be visited during the week were in attendance. At the conclusion 

of the opening meeting, we traveled directly to the City Rescue Mission–New Life Inn. After 

we unloaded our ventilation equipment, the shelter administrator provided a tour of the facility and explained the various programs and general flow of shelter guests. 

After the tour, we began taking physical and ventilation measurements in all key areas of the 

facility. We focused on areas where New Life Inn guests typically congregate or spend significant amounts of time. The dining/assembly area (1st floor), work program sleeping area 

(2nd floor), and the LifeBuilders program and overnight sleeping areas (3rd floor) were the 

areas of primary concern. However, we took measurements throughout the entire facility.

We recorded the make and model number of all nine air-handling units (AHUs) providing supply air to the facility, and we visually inspected all of the units. When possible, we 

measured the air flow rate through supply diffusers and return grilles using a TSI Incorporated (Shoreview, Minnesota) Model 8373 Accubalance Plus equipped with an appropriate 

air capture hood. The Model 8373 measures volumetric air flow rates of 30–2000 cubic 

feet per minute (cfm) with an accuracy of ±5% of the reading and ±5 cfm. The Accubalance Plus is also equipped with a directional air flow indicator that provides confirmation of 

flow direction. We determined the approximate internal volume of the measured spaces with 

either a standard tape measure or a Zircon Corporation (Campbell, California) Model 58026 

LaserVision DM200 laser distance measuring device. The device accurately measures up to 

200 feet and has function keys for calculating the area and volume of a room for HVAC load 

formulas. When the existence of air flow or the air flow direction was questioned, we used 

a Wizard Stick hand-held fog generator (Zero Toys, Concord, Massachusetts) to confirm and 

visualize the air flow pattern.

After recording our measurements, we met briefly with the New Life Inn administrator on 

August 20, 2012 to discuss our general findings from the day’s assessment. A formal closing 

meeting for our on-site response to the technical assistance request for all four of the facilities was held on August 23, 2012, at the DCHD. This meeting provided us an opportunity to 

discuss our general findings with representatives from the Duval County Health Department. 

Results and Discussion

General Tuberculosis Infection Control

All tuberculosis control programs should include three key components: administrative controls (e.g., intake questionnaires and policies), environmental controls (e.g., ventilation and 

filtration), and a respiratory protection program. Ideally, environmental controls and respiratory protection should supplement aggressive administrative controls. Detailed explanations 

for each of these key control elements, as well as a discussion on the hierarchy of their implementation, are outlined in CDC’s Guidelines for Preventing the Transmission of Mycobacte-
Health Hazard Evaluation Report 2012-0155-3180 Page 5

rium tuberculosis in Health-Care Settings, 2005 and Prevention and Control of Tuberculosis 

in Correctional and Detention Facilities: Recommendations from CDC [CDC 2005b, 2006]. 

In high risk environments, such as homeless shelters, or in areas where administrative controls alone are inadequate, environmental controls and respiratory protection should be used 

as secondary and tertiary levels of control, respectively.

Administrative Controls

During our visit, and in previous conversations with representatives from DTBE, the Florida 

Department of Health, DCHD, and New Life Inn, it was apparent that limited TB administrative controls were in place at the shelter prior to the current disease outbreak. However, efforts were taken to improve the overall administrative controls in place at the time of the site 

visit. Employees and volunteers were trained on symptoms of TB disease and prevention of 

TB transmission. Additionally, intake screening procedures are now in place to help identify 

guests on target screening lists, or others suspected of having TB, and refer them to DCHD 

for critical medical screening. These procedures will help identify infected individuals more 

rapidly in the future and serve to help keep infected guests away from those that are healthy. 

We cannot overstate the importance of having robust administrative controls in place. As 

with most homeless facilities, New Life Inn frequently provides services to large numbers 

of guests in very close proximity to one another. This is particularly the case in the congregate sleeping areas on the second and third floors, along with the ground floor dining room 

during meals and when the space is used to house overflow guests. Even the best ventilation systems are incapable of preventing the spread of disease between guests close to one 

another. Thus, identifying people with suspected disease, keeping them separated from the 

general guest population, and following up with appropriate medical evaluations and treatment (if necessary) are the most important elements of reducing or eliminating the spread of 

disease. While enhancing administrative controls is a significant step, the development of a 

written TB Infection Control Plan (ICP) for the shelter should be considered. At the time of 

the NIOSH investigation, no such ICP was reported to exist. Information on creating detailed 

ICPs and TB ICP templates for homeless shelters can be found at the Curry International Tuberculosis Center website at http://www.currytbcenter.ucsf.edu/. Collaborating with DCHD 

and the Florida Department of Health would serve to further strengthen the written plan. 

These ICPs are particularly useful when overall TB infection control requires the coordination and subsequent follow-up of different agencies. In response to this current TB outbreak, 

there was good communication and coordination between New Life Inn and DCHD. However, the process should be formally documented in a protocol or checklist format. This 

ensures that each time there is a TB-related incident, all necessary agencies understand their 

responsibilities and perform their necessary predetermined actions in a consistent manner. 

Incorporating the input of staff involved in the maintenance and operation of facility ventilation systems into the overall infection control program strengthens the program and provides 

these staff members with additional insight as to what ventilation requirements are necessary 

to prevent and/or isolate TB disease. Input from the ventilation staff should be sought during 

the formal creation of the ICP and during subsequent revisions to the plan. 
Page 6 Health Hazard Evaluation Report 2012-0155-3180

Environmental Controls

General Ventilation System Information

General information on the AHUs at New Life Inn, including the areas served by each unit, is 

provided in Table 1. Of the nine AHUs, units from five different manufacturers are installed 

throughout the shelter, and the units range in size and age. Each of the AHUs supply air to 

occupied spaces through uninsulated, galvanized steel supply ducts. Return air flows back 

to the units through a combination of ducted returns, ceiling plenums, and holes in the doors/

walls to the mechanical spaces. None of the AHUs delivered fresh outdoor air into the buildings.

With the exception of the Annex, the mechanical spaces housing the AHUs were clear and 

free of clutter. All AHU air filters were changed just prior to the NIOSH visit. As shown in 

Table 1, AHU-1 did not have a filter installed in the unit itself. Four other AHUs had filter 

sizes/configurations that differed from manufacturers’ recommendations. While these filters 

provided some filtration, the level was uncertain as the deviation from intended design provides ample opportunity for filter failure and bypass. On the day of our visit, all of the AHUs 

were operational and capable of maintaining temperature set points and air flow. However, 

there were some issues with controlling condensate from the cooling coils. AHU-1 on the 

first floor was dripping substantial amounts of condensate onto the floor of the mechanical 

room (Figure 1). Similarly, AHU-6 on the second floor was dripping condensate inside the 

mechanical room, including inside the return air ductwork of the AHU (Figure 2). Finally, 

the drain pan on AHU-8 (third floor) was completely full of water and was overflowing into 

the mechanical space (Figure 3). The excess moisture resulting from these condensate leaks 

is a recognized contributor to the development of microbial growth of public health concern 

[NIOSH 2013]. Proper slope of mechanical room floors, condensate pans, and clean unobstructed drain lines that route condensate into mechanical room floor drains should eliminate 

these moisture accumulation problems. 

Filtration

All of the ventilation filters used at New Life Inn were Flanders Corporation (Washington, 

North Carolina) Pre Pleat 40 LPD pleated filters. The Pre Pleat 40 LPD filters have an 

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 

Minimum Efficiency Reporting Value (MERV) of 8, which corresponds to a removal efficiency of greater than 70% for 3.0 to 10 micrometer (μm) particles [Flanders 2011; ANSI/

ASHRAE 2007]. However, MERV 8 filters are only around 25% efficient at filtering particles in the 1.0–3.0 μm size range, which includes droplet nuclei responsible for M. tuberculosis transmission [ANSI/ASHRAE 2007]. 

To prevent the spread of M. tuberculosis, air filters should provide a removal efficiency of 

greater than 90% of particles in the 1.0–3.0 μm size range (corresponding to a MERV 13 or 

higher). During any future HVAC design modifications, system evaluations, or retrofits, the 

selection of filters for use in the AHUs, especially those serving the three main overnight 

sleeping areas, should be closely examined. Care should be taken when choosing more efficient filters, because increased efficiency is typically associated with increased pressure drop 

across the filter (resistance to air flow). Filters in the AHUs should have the highest possible 
Health Hazard Evaluation Report 2012-0155-3180 Page 7

efficiency (i.e., highest MERV rating) while still maintaining the air flow required for conditioning and outdoor air supply through each system.

Ultraviolet Germicidal Irradiation (UVGI) Units

AHU-3, providing supply air to the dining/assembly area on the first floor, had a Fresh-Aire 

(Jupiter, Florida) ultraviolet (UV) disinfection system installed inside. This UV system is 

designed solely to kill or inactivate bacteria and mold growing on the coil and other exposed 

surfaces. While these UV units work to keep coils and surfaces clean, it is important to note 

that they are not designed to kill or inactivate microorganisms suspended in the airstream 

as it moves through the AHU. The system was noticeably working to keep the coil clean, 

and should continue to be used to avoid microbial buildup that is associated with indoor air 

complaints, dampness-related asthma, and upper respiratory symptoms [NIOSH 2013]. UV 

lamps should be replaced annually or when they burn out, whichever comes first.

While there are labels affixed on the outside of AHU-3 stating clearly that UV lamps are 

inside, CDC recommends additional safety devices when in-duct UV fixtures are used [CDC 

2005b]. First, there should be a small viewport or window installed in each AHU access 

panel so maintenance personnel can see when the lamps are on or burned out. The blue 

glow through the window, while harmless, also serves as a reminder that the lamps need 

to be powered down before opening the access panels. Along with the viewport, a safety 

switch should be installed on each access panel to power down the lamps when the access 

panels are removed. Otherwise, forgetting to power down the AHU and opening the access 

panels could easily result in unnecessary UV exposures to workers. In humans, UV may be 

absorbed by the outer surfaces of the eyes and skin. Short-term overexposure may result in 

photokeratitis (inflammation of the cornea) and/or keratoconjunctivitis (inflammation of the 

conjunctiva). More details on UVGI installation, operation, and maintenance can be found in 

ASHRAE, NIOSH, and CDC documents [ASHRAE 2012; NIOSH 2009; CDC 2005b, 2006]. 

Any time that UVGI fixtures are installed inside AHUs, care needs to be taken to protect 

all nonmetallic surfaces exposed to UV energy. Synthetic filter material, such as that in the 

Flanders Pre Pleat 40 LPD filters used in all New Life Inn AHUs, is highly susceptible to UV 

degradation and should not be used in AHUs where the filters are in direct line-of-sight of the 

UV lamps [ASHRAE 2012]. If degradation of the synthetic filters is noticed, a switch to fiberglass filters is recommended. Fiberglass filter material does not degrade with exposure to 

UV energy, although some binding materials holding the fibers together can still be degraded. 

A reputable ventilation filter manufacturer could help select appropriate fiberglass filters for 

use around UV, if necessary. In addition to ventilation filters, all other nonmetallic materials, such as seals, gaskets, fan belts, and electrical wiring insulation, may be degraded by UV 

energy. These materials should be protected with foil tape or metal guards, if necessary. If 

any degradation becomes evident inside the AHU, the degraded material should immediately 

be replaced with new material that is properly shielded from the lamps or has been tested to 

be UV-resistant.

Preventive Maintenance

The ventilation system preventive maintenance program at New Life Inn was coordinated 

by the facilities manager. With the exception of the condensate issue, all of the AHUs were 
Page 8 Health Hazard Evaluation Report 2012-0155-3180

fairly clean and appeared to be adequately maintained. The facilities manager informed us 

that the ventilation filters are changed at least quarterly. Unfortunately, there is no written 

plan outlining the preventive maintenance schedules and procedures for HVAC systems. A 

written HVAC operation and maintenance (O&M) plan should be developed. Currently, 

all preventive and emergency maintenance is managed, scheduled, and coordinated by the 

facilities manager. Actual tasks are performed by staff, volunteers or contractors, depending 

upon complexity. While this seems to be effective at the present time, there could be a void 

if the facilities manager leaves his current position or is unavailable for any significant period 

of time. Combining all maintenance tasks, schedules, procedures, and training requirements 

into a written plan would help ensure that all equipment is properly maintained at appropriate 

time intervals and that any emergency maintenance issues are addressed correctly. A detailed 

plan would also help ensure that the quality of work remains consistent as staff changes. 

Once developed, this written plan should be revised periodically to be current with any ventilation system and equipment modifications at the facility.

Ventilation Measurements and Indoor Air Quality

An adequate supply of outdoor air, typically delivered through the HVAC system, is necessary in any indoor environment to dilute pollutants that are released by equipment, building 

materials, furnishings, products, and people. In the State of Florida, the 2010 Florida Building Code mandates “minimum requirements to safeguard the public health, safety and general welfare through structural strength, means of egress facilities, stability, sanitation, adequate 

light and ventilation, energy conservation, and safety to life and property from fire and other 

hazards attributed to the built environment and to provide safety to fire fighters and emergency responders during emergency operations [ICC 2011].” The Florida Building Code applies 

to the “construction, alteration, movement, enlargement, replacement, repair, equipment, use 

and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures” throughout 

the state. The Code is based on a variety of model building codes and consensus standards 

from national organizations, which have been modified to fit Florida’s specific needs, when 

necessary. When it comes to ventilation standards, in most cases, the Florida Building 

Code has adopted the recommendations published in American National Standards Institute 

(ANSI)/ASHRAE Standard 62.1-2010: Ventilation for Acceptable Indoor Air Quality. These 

ASHRAE recommendations provide specific details on ventilation for acceptable indoor air 

quality [ANSI/ASHRAE 2010a]. 

The 2010 Florida Building Code and ASHRAE 62.1-2010 recommend outdoor air supply 

rates that take into account people-related contaminant sources as well as building-related 

contaminant sources. Similarly, exhaust air flow rate requirements for some spaces are also 

listed. Although there are no specific guidelines for homeless shelters and related facilities, 

there are published guidelines applicable to New Life Inn. These outdoor air supply and 

exhaust air requirements are summarized in Table 2. Table 2 also lists the default occupant 

densities for various spaces. These default values, given in terms of number of occupants per 

1000 square feet, are provided by the Florida Building Code and ASHRAE to assist building 

and HVAC system designers when actual occupant densities are unknown. Although actual 

occupant densities for the occupied spaces of the shelter are generally known, the default 
Health Hazard Evaluation Report 2012-0155-3180 Page 9

values still serve as a reference to determine whether the occupant density in a given space is 

higher or lower than what is considered typical.

The physical and ventilation measurements we collected are presented in Table 3. The 

second-to-last column of the table presents the actual occupant densities in each space. 

Values preceded by an asterisk (*) denote areas with occupant densities above typical values 

(i.e., higher than the default values presented in Table 2). High occupant densities are not 

solely indicative of ventilation problems. For instance, all of the offices on the first and second floors with high densities are typically only occupied by one person. In these cases, the 

occupant densities are high simply because the offices are smaller than typical office spaces. 

However, the two sleeping areas on the third floor show high occupant densities because 

many people actually sleep in close proximity to one another. The work program sleeping 

area on the second floor is also close to exceeding the default occupant density value. In 

these cases, special consideration should be given to air flow patterns in the spaces to minimize the potential of exhalations from one person passing through the breathing zone of multiple other people. This is especially true when airborne disease transmission is a concern. 

The last column in Table 3 presents the outdoor air requirements for each space, as established by the 2010 Florida Building Code and ASHRAE. As previously noted, none of the 

AHUs at New Life Inn were delivering fresh outdoor air into the building. With one exception, the AHUs were not installed in a way that would allow them to easily bring outdoor 

air into the buildings. Some AHUs may not have the tempering capacity to incorporate the 

introduction of outdoor air. If such capacity is available, introducing outdoor air through the 

AHU would require some modifications, as well as increased annual energy costs. However, 

it is important to ensure that all occupied spaces in New Life Inn are receiving adequate 

amounts of fresh outdoor air. In addition to alleviating odors and better maintaining occupant comfort, outdoor air serves to dilute infectious aerosols, such as M. tuberculosis droplet 

nuclei. 

Two common approaches could be employed by New Life Inn to introduce outdoor air into 

the occupied spaces (or a combination of the two). The first approach would be to make the 

necessary modifications to the existing AHUs to allow them to bring in the required outdoor 

air. This would initially require evaluation, by a knowledgeable HVAC engineer (a reputable 

ventilation or engineering design contractor that is familiar with ASHRAE, Facility Guidelines Institute (FGI), and CDC guidelines and recommendations), of each AHU’s conditioning capacity to determine if it can handle the additional tempering and dehumidification 

burden introduced by the outdoor air. The AHU system modifications would require the 

installation of outdoor air intakes and dampers into each mechanical space housing an AHU. 

Depending upon the age/condition of some of the AHUs, replacement of an older AHU could 

be a cost-effective contribution to this approach. Although this may be the simpler of the 

two solutions and could require the least capital expense, it may cost significantly more in 

energy over time. In their current configurations, the AHUs are simply recirculating air that 

is relatively close to the desired indoor temperature and humidity conditions. After circulating through the occupied space, this air requires less conditioning to return it to the desired 

delivery temperature and humidity levels. Once outdoor air is mixed in with the room return 

air, the mixed air stream introduced to each AHU will be further from the desired indoor 
Page 10 Health Hazard Evaluation Report 2012-0155-3180

conditions for most of the year. Each AHU will then need to work harder to dehumidify and 

temper the mixed air stream. 

A second common method of bringing outdoor air into the shelter would be to install a 

dedicated outdoor air system. This would involve installing a completely new AHU with 

ductwork extending to all occupied spaces of the main building. The same strategy could 

be applied for the Annex with a separate dedicated outdoor air system for that space. This 

new AHU should be sized to provide adequate outdoor air flow for the entire main building (approximately 2500–3000 cfm) while also providing the entire capacity to temper and 

dehumidify this outdoor air. The new AHU should provide tempered and dehumidified (supercooled to 45°F–50°F dew point) outdoor air to each space (or existing AHU) in quantities 

necessary to meet Florida Building Code and ASHRAE outdoor air requirements. Terminal 

reheating or blending of this air with air delivered by the primary AHUs may be necessary to 

prevent thermal discomfort from the supercooled outdoor air. Conversely, multiple smaller 

dedicated outdoor air systems could serve the same purpose as one large system for the entire 

main building. Regardless of how it is accomplished, the major advantage of the dedicated 

outdoor air system is that it would not require major modifications to the existing AHUs, 

which would simply continue to recirculate air through the spaces they serve while providing 

air filtration, heating and cooling. The dedicated outdoor air system would certainly require 

more capital expense and more excessive renovations for the required ductwork than the 

first option, but it could also provide significant energy cost savings, making it a more viable 

long-term solution.

A knowledgeable HVAC engineer should be consulted to discuss these and other potential 

options for introducing outdoor air into the shelter. At the same time, consideration should be 

given to optimizing air flow patterns, particularly in the three large sleeping areas, to reduce 

the potential of airborne disease transmission between guests. While even the best ventilation system cannot guarantee prevention of disease transmission between people in close 

proximity to one another, improving air flow patterns could help reduce the overall transmission potential among guests in each sleeping area. One way that air flow patterns could be 

improved in these areas is to supply all air (fresh and recirculated) above the center aisles 

between rows of beds using supply diffusers designed to discharge the air in a wide, downward deflected angle. At the same time, return grills should be installed in the ceiling along 

both outside walls of each space, parallel to the rows of beds. In this arrangement, supply air 

will generally pass over/across each bed and directly back to the AHU. This will reduce the 

potential of exhalations from one person passing through the breathing zone of multiple other 

people sharing the space. This arrangement should also alleviate concerns with short-circuiting of air, where supply air is immediately pulled into a return grille without providing any 

useful ventilation. A qualified HVAC/ventilation engineer might recommend other air flow 

schemes that could be similarly effective at providing adequate ventilation while minimizing the potential for disease transmission. The final chosen design scheme should be smoke 

tested to verify performance.

We also noticed that virtually none of the bathroom exhaust fans were operational during 

our visit (see Table 3). To control humidity and odors, bathrooms and shower areas should 

exhaust more air than the AHU is supplying. This will maintain these areas under negative 
Health Hazard Evaluation Report 2012-0155-3180 Page 11

pressure. Separate exhaust fans should be used to exhaust air directly outside at least 25 feet 

from any air intakes; there should be no recycling or re-entrainment of return/exhaust air 

from the bathrooms and shower rooms. For high occupancy public bathrooms, 50 cfm of exhaust per toilet/urinal is recommended. For private toilets in bathrooms intended to be occupied by only one person at a time, ASHRAE 62.1-2010 specifies that the exhaust ventilation 

should be 25 cfm if the exhaust fan is designed to operate continuously (the Florida Building Code only requires 20 cfm) or 50 cfm if the exhaust fan only operates during periods of 

occupancy (e.g., exhaust fan controlled by a wall switch). All bathroom and shower exhaust 

fans should be made functional with their exhaust rates verified for compliance with the 2010 

Florida Building Code, and they should be operational whenever the rooms are occupied. 

[Note: The kitchen hood exhaust system was not evaluated at the time of the NIOSH site 

visit due to ongoing meal preparation activities. This exhaust was reportedly paired with its 

own makeup air system. Neither of these systems is discussed within this report.] 

While not a major concern from an airborne disease transmission standpoint, temperature 

and relative humidity (RH) affect the perception of comfort in an indoor environment. The 

perception of thermal comfort is related to one’s metabolic heat production, the transfer of 

heat to the environment, physiological adjustments, and body temperature. Heat transfer 

from the body to the environment is influenced by factors such as temperature, humidity, air 

movement, personal activities, and clothing. ANSI/ASHRAE Standard 55-2010: Thermal 

Environmental Conditions for Human Occupancy specifies conditions in which 80% or more 

of the occupants are expected to find the environment thermally acceptable [ANSI/ASHRAE 

2010b]. Assuming slow air movement and 50% RH, the operative temperatures recommended by ASHRAE range from 68.5–76o

F in the winter, and from 75.5–80.5oF in the summer 

(see Table 4). The difference between the two temperature ranges is largely due to seasonal 

clothing selection. ASHRAE also recommends that RH be maintained at or below 65%. The 

U.S. Environmental Protection Agency recommends maintaining indoor relative humidity between 30–50% because excessive humidity can promote the growth of microorganisms [EPA 

2012]. Temperature and RH levels were not recorded during our visit because the main guest 

spaces were generally empty. We recommend maintaining the indoor temperature and RH 

levels within the ranges established by ASHRAE to provide the most comfortable environment to guests at New Life Inn. Meeting the 30–50% RH recommendation would be significantly easier if a dedicated outdoor air system is installed to introduce conditioned outdoor 

air to the shelter, as explained above. 

Respiratory Separation Areas

Currently, New Life Inn does not have areas set aside for separating guests suspected of 

having TB or other respiratory diseases from the remainder of the guest population. Rapidly 

identifying people with suspected TB disease and keeping them separated from others until 

appropriate medical evaluations and treatments are initiated is one of the most important 

elements in reducing or eliminating the spread of airborne disease. As such, we strongly 

recommend identifying an area that can be used for respiratory separation when needed. It is 

important to recognize that respiratory separation is not an alternative to medical evaluation. 

Rather, it is proposed to be a temporary holding area for guests awaiting transport for medical evaluation. It may also be used to house guests exhibiting signs of respiratory distress 
Page 12 Health Hazard Evaluation Report 2012-0155-3180

without having disease. When respiratory separation is not required, the area can be used for 

normal guest housing or other purposes.

A respiratory separation area is not intended to be equivalent to an airborne infection isolation (AII) patient room found in hospitals and other healthcare settings. However, it can be 

designed using some of the same protective concepts, namely negative room pressure and 

elevated ventilation rates. The respiratory separation area should be maintained under negative pressure relative to the adjacent spaces. This means that air from outside the respiratory 

separation area should migrate inwards into the respiratory separation area and not in the 

opposite direction. This is easily maintained by exhausting more air from the respiratory 

separation area than is being supplied. Operable windows, either within the respiratory separation area or in adjacent areas, should not be allowed to interfere with this intent. Negative 

pressure helps reduce the potential that any guest housed in the respiratory separation area 

with active TB disease (or any other disease where airborne infection is a concern) could 

expose other healthy individuals in adjacent areas. In addition to maintaining negative pressure, all return air from the respiratory separation area should preferably be exhausted directly outside. In no circumstances should air from the respiratory separation area be allowed to 

re-infiltrate the building or go back through the AHU without first having passed through a 

high-efficiency particulate air (HEPA) filter.

For true AII rooms in healthcare facilities, the CDC and FGI recommend a differential pressure of >0.01 inches of water gauge (2.5 Pascals [Pa]) across the closed door between the 

isolation area and adjacent areas [CDC 2005b; FGI 2010]. Although the minimum pressure 

difference needed for maintaining airflow into a room is quite small (about 0.001 inches of 

water gauge), the higher prescribed pressure differential is easier to measure and maintain as 

the pressure in surrounding areas changes due to the opening and closing of doors, ventilation system fluctuations, and other factors. The FGI and CDC also recommend a total of 

12 air changes per hour (ACH) through the isolation room (CDC allows 6 ACH for existing 

AII rooms) and at least 2 ACH of fresh outdoor air. True AII rooms are designed to house 

individuals with confirmed respiratory disease. A respiratory separation area at New Life 

Inn would not be used to house guests with confirmed disease, so it would not be necessary 

to meet the strict air flow and differential pressure requirements detailed above. However, 

knowledge of the AII design strategies could be useful in designing a respiratory separation 

area. It is vastly more important to establish a negative pressure area that can be used for 

respiratory separation than it is to focus on the respiratory separation area meeting quantitative ventilation requirements.

During our visit, we identified the three transition housing rooms on the second floor as 

areas that might be converted to effective respiratory separation areas. One of these transition rooms should be upgraded to serve this purpose. All of the transition rooms receive and 

return air to AHU-4, and they are the only areas served by AHU-4. One of these rooms could 

be converted for respiratory separation by 1) installing a solid, sealed ceiling in place of the 

existing drop ceiling or ensuring the walls for the selected room extend to the hard ceiling 

above the current drop ceiling, 2) installing a new exhaust fan through the outside wall of the 

selected room to provide the required exhaust air flow, and 3) installing tight-closing dampers 
Health Hazard Evaluation Report 2012-0155-3180 Page 13

(or some other mechanism) to completely seal all existing air returns from the selected room 

to AHU-4. Choose an exhaust fan that is capable of maintaining the room under negative 

pressure relative to the adjacent corridor with minimal noise. The fan could be mounted directly in the wall or on the roof with ductwork running through the wall and up to the fan on 

the outside of the shelter. It is imperative that exhaust air from the new fan is directed away 

from all future AHU air intakes and gathering areas outside the shelter. Given that these 

rooms are located on the second level of the shelter, this should not be difficult.

For the space selected for respiratory separation, the newly installed return air dampers 

should be sealed to prevent air from inside the room returning to AHU-4. The new exhaust 

fan should also be activated to maintain the space under negative pressure. For the majority 

of the time, when respiratory separation is not required, the room can be used as normal by 

shutting down the exhaust fan and reopening the return air dampers back to AHU-4.

While it would be prudent to verify prior to any system renovations, AHU-4 should be able 

to self-balance if the return air grille from only one transition room is blocked. If additional 

respiratory separation areas are desired, the remaining transition rooms on the second floor 

could also be converted for this purpose. However, additional ventilation modifications 

may be required to ensure AHU-4 has an adequate supply of return air during periods when 

multiple rooms are simultaneously used for respiratory separation (and the normal return 

air paths from the rooms are blocked). To provide AHU-4 with the required return air flow, 

an alternative return air duct/damper system could be installed to pull air from an adjacent 

space. This alternative return air system would only be used when multiple transition rooms 

are simultaneously used as respiratory separation areas. Care should be taken when choosing 

the alternative air return location so undesirable pressure relationships and air flow patterns 

do not result when the system is in operation.

For any respiratory separation area, a written plan for testing and operating the space is 

recommended. At New Life Inn, a detailed written plan should be developed for the rapid 

conversion of the room from standard housing area to use for respiratory separation. The 

plan should include contingency plans for moving the guests currently housed in the space to 

other locations, steps for cleaning and refurnishing the area for separation purposes, and stepby-step procedures for shelter staff to follow to effectively initiate respiratory separation.

The respiratory separation area should be visually tested daily to ensure negative pressure 

is being maintained while the area is occupied for separation purposes. Testing can be done 

cheaply and easily with tissue flutter strips or smoke tubes. The results of the testing should 

be documented each day when in use. When the room is being used as a standard housing 

unit, it should be tested a minimum of once per month to ensure proper operation in the event 

it would be needed for respiratory separation.

Auxiliary HEPA Filtration

The higher the dilution ventilation rate within a given respiratory separation area, the faster 

the room air will be cleared of existing airborne pathogens. In order to increase effective 

ventilation within a separation area, in-room HEPA filtration units may be used. These units 

may be portable or permanently-mounted somewhere within the room. Some models can be 
Page 14 Health Hazard Evaluation Report 2012-0155-3180

ceiling mounted, which could reduce the potential for tampering. If such units are used, their 

placement and discharge orientation must be selected, installed, and maintained carefully to 

maximize room air mixing effectiveness without disrupting the desired flow of air into the 

respiratory separation area.

One unique use of portable HEPA filtration units is through ventilated headboards. The 

ventilated headboard is a NIOSH-developed technology that consists of lightweight, sturdy & 

adjustable aluminum framing with a retractable plastic canopy sheeting that can extend over 

the pillow area of a cot, mat or bed. Low-velocity airflow into the canopy is created using 

a high-efficiency fan/filter exhaust unit. This local control technique allows for near-instant 

capture of any aerosol originating from the patient while simultaneously providing air cleaning to the entire room. NIOSH engineers are available to provide additional information or 

to assist in the selection and acquisition of ventilated headboards.

Respiratory Protection

During an outbreak of airborne infectious disease, there could be instances when staff members or volunteers find themselves in close contact with guests suspected of being infectious. 

One example would be a van driver transporting a guest to a medical facility for TB testing. 

Ideally, these cases would be identified during the administrative screening process. When 

these circumstances cannot be avoided, it is wise to consider the availability of respiratory protection to protect staff and volunteers. The first step toward the implementation of 

respirator use is to develop a document that clearly outlines a formal respiratory protection 

program. The Occupational Safety and Health Administration (OSHA) Respiratory Protection standard (29 Code of Federal Regulations [CFR] 1910.134) outlines the requirements 

for comprehensive respiratory protection programs. In accordance with 29 CFR 1910.134, a 

written Respiratory Protection Program, with an identified program administrator, is required 

for any facility that requires employees to wear respirators. The program must include training, medical evaluations, and respirators at no cost to employees or staff required to wear 

respirators on the job. Initial fit testing by a trained individual is required for all employees 

that will potentially wear a respirator. Annual fit testing is required after that, with additional 

fit testing upon major changes to the facial features of the respirator user (i.e. major weight 

gain/loss, change in facial hair, scarring, etc.). 

To comply with applicable OSHA regulations regarding respiratory protection, we recommend that the shelter create a written respiratory protection program as outlined in 29 CFR 

1910.134, appoint a program administrator, and initiate training and initial fit testing for employees. Many online resources exist to assist in the development of a respiratory protection 

program. OSHA has published a Respiratory Protection informational booklet online (http://

www.osha.gov/Publications/OSHA3079/osha3079.html) and a more detailed Small Entity 

Compliance Guide for the Revised Respiratory Protection Standard (http://www.osha.gov/

Publications/3384small-entity-for-respiratory-protection-standard-rev.pdf) to explain all parts 

of an appropriate respiratory protection program and how to comply. The Small Entity Compliance Guide also contains a sample respiratory protection program in Attachment 4 that 

can be used as a model program. The Washington State Department of Labor and Industries 

has also developed a user-friendly, fillable template that is helpful in developing a respiratory 
Health Hazard Evaluation Report 2012-0155-3180 Page 15

protection program at http://www.lni.wa.gov/Safety/Basics/Programs/Accident/Samples/RespProtectguide2.doc.

The DCHD, Florida Department of Health, local healthcare facilities, or fire/ambulance 

stations can potentially assist with training and fit testing the employees required to wear 

respirators. Alternatively, qualitative fit testing kits (BitrixTM) can be purchased for around 

$200.00. When paired with a trained and competent fit test administrator (see 29 CFR 

1910.134), these kits would allow cost-effective, on-site fit testing annually.

Conclusions 

Since the increase in cases of TB disease in 2010, New Life Inn has taken significant steps to 

improve the administrative controls at the shelter. The shelter has developed important lines 

of communication with DCHD, and improved staff training and awareness of TB symptoms. 

Identifying guests with symptoms of TB disease or those listed on the DCHD target screening lists will help further reduce the potential for future cases of TB disease and bring the 

ongoing outbreak under control. Having consistent protective strategies upon suspect case 

identification is also important. While enhanced administrative controls are now in place, 

there is no written ICP established at the shelter, and New Life Inn administrators are encouraged to promptly coordinate with DCHD and the Florida Department of Health to establish 

one. 

From an environmental control perspective, the nine AHUs at the shelter are models from 

five different manufacturers and are of various sizes and ages. The preventive maintenance 

program in place is managed by the current facilities manager. The units appear to have been 

adequately maintained and were fully operational at the time of the NIOSH visit, although 

some had improper filter configurations and condensate containment and drainage problems 

that need to be addressed. There was no written preventive maintenance or O&M plan for 

the shelter AHUs. 

None of the AHUs at New Life Inn were providing fresh outdoor air to the occupied spaces, 

as required by the 2010 Florida Building Code and ASHRAE guidelines. Given the number 

of guests served by shelter and the close proximity of guests to one another in most of the 

occupied spaces, it is important that these spaces are receiving adequate amounts of outdoor 

air. In addition to alleviating odors and better maintaining occupant comfort, outdoor air 

serves to dilute infectious aerosols, such as M. tuberculosis droplet nuclei responsible for TB 

transmission. With renovations, the existing AHUs might be made to provide the necessary 

outdoor air, or they could be augmented with the installation of new, dedicated outdoor air 

systems to provide the necessary outdoor air. A qualified HVAC engineer should be consulted to discuss options for introducing outdoor air to the shelter. Once these changes have 

been implemented, other ventilation equipment and/or supplemental ultraviolet germicidal 

irradiation systems could be investigated if additional environmental controls are desired.
Page 16 Health Hazard Evaluation Report 2012-0155-3180

For instances where improvements to administrative and environmental controls do not 

sufficiently mitigate the risk for disease transmission, respiratory protection might be necessary. There was no formal respiratory protection program in place during our visit, but such 

a program should be implemented at the shelter. Having this program in place will provide 

additional protection to New Life Inn staff and volunteers working in close proximity to 

guests with suspected TB or other airborne diseases. Any respirator use at the shelter should 

be covered by an OSHA-mandated respiratory protection program.

Administratively, a positive approach is being taken toward reducing the likelihood of future 

TB transmission at New Life Inn. However, the ventilation systems clearly need some attention to further reduce the risk. While ventilation systems and other environmental control systems cannot guarantee prevention of future TB disease transmission, improving the 

environmental controls will reduce the potential for airborne disease transmission, along with 

providing better indoor air quality throughout the shelter. The following recommendations 

are aimed at improving the overall infection control program at New Life Inn, with emphasis 

on improvements to the existing environmental controls so they meet all applicable standards 

and guidelines.

Recommendations 

Based on our assessment of environmental controls at New Life Inn, we have developed the 

following list of recommendations, in order of priority:

1. Continue to improve and enhance the TB administrative controls at the shelter 

and develop a written Infection Control Plan.

● Continue working with the DCHD to screen shelter staff, volunteers, and 

guests for TB disease.

● With input from DCHD, develop specific procedures for handling a suspected 

or confirmed case of TB disease.

● Continue educating shelter staff and volunteers on the signs and symptoms 

of TB disease so they can readily identify suspect cases and implement 

established precautions.

● Consider displaying informational posters about TB signs and symptoms to 

educate guests.

● Consider displaying signs encouraging proper cough etiquette and hand 

hygiene.

● Develop a formal written TB Infection Control Plan. Seek guidance and input 

from DCHD and the Florida Department of Health. The plan should include:

○ All aspects of the TB infection control program and associated 

responsibilities, especially those functions requiring coordination with 
Health Hazard Evaluation Report 2012-0155-3180 Page 17

other agencies, such as the local and state health departments

○ The improved administrative controls put in place at New Life Inn 

since the beginning of the TB outbreak

○ Input from ventilation staff and/or guests tasked with servicing 

ventilation systems. Obtaining input from ventilation maintenance 

staff serves to strengthen the environmental control section of the plan 

while giving maintenance staff additional insight into the ventilation 

requirements for reducing or preventing airborne disease transmission

○ Schedule for updating and revising the ICP

2. Introduce the required amounts of fresh outdoor air to all occupied spaces.

● There are multiple options that can allow adequate outdoor air to be supplied 

to the shelter. All options, including the associated capital, maintenance, 

and annual operating costs should be considered. Work with a reputable 

ventilation or engineering contractor familiar with the current Florida 

Building Code, ASHRAE, FGI, and CDC guidelines to select the best option 

for New Life Inn.

● Improve air flow patterns within all occupied spaces, particularly the three 

large sleeping areas. Air flow patterns should provide effective ventilation and 

temperature control while minimizing the number of people that air travels 

across before returning to the AHU. 

● Determine and fix the cause of condensate leaks with AHU-1, AHU-6, and 

AHU-8. Develop a monitoring strategy to prevent further occurrence of 

condensate buildup within the mechanical rooms. 

● After the condensate issue in AHU-1 is resolved, install a proper filter in 

that unit, which serves the registration/lobby area of the first floor. The 

filter through the door into the mechanical room housing AHU-1 can stay in 

place to provide additional air filtration if desired, but a filter is needed in the 

AHU itself to protect against aerosols generated within or leaking into the 

mechanical space.

3. Improve filtration efficiency in all AHUs. Select higher efficiency filters (higher 

MERV ratings) for use in each AHU, as long as the new filters do not adversely impact 

the required air flow delivery capacity of the AHUs.

4. Modify at least one transition room on the second floor into a respiratory 

separation area.

● Choose a reputable ventilation or engineering design contractor that is familiar 
Page 18 Health Hazard Evaluation Report 2012-0155-3180

with current Florida Building Code, ASHRAE, FGI, and CDC guidelines 

and recommendations. While there are various ways to develop a respiratory 

separation area, it should include the following:

○ Ensure that all supply and return ductwork for AHU-4 is intact and 

sealed. Install tight-sealing return dampers on each return from the 

selected transition room to eliminate return air flow when the space 

is used for respiratory separation. Ensure that supply air diffusers 

provide good air mixing and air flow patterns in each selected room.

○ Design and install an auxiliary exhaust system that enables the 

respiratory separation area to be maintained under negative pressure 

when housing guests for separation purposes. One approach to 

this requirement would be to select and install exhaust fans directly 

through the outside walls of the rooms. The fans can be mounted 

through the walls themselves or mounted on the roof with ductwork 

through the walls to the fans.

○ Install the highest efficiency air filters in AHU-4 that will still allow 

adequate airflow to meet the AHU’s conditioning requirements. Adjust 

and balance the system as necessary to ensure proper air flows at all 

times when each selected room is individually or collectively used 

for respiratory separation and normal purposes. Ensure that adequate 

outdoor air is supplied to each space at all times (see Recommendation 

2 above).

○ Develop a detailed written plan for the conversion of the selected 

transition room(s) from normal housing functions to use for respiratory 

separation. The plan should include:

▪ Procedures for moving the guests currently in these areas to 

other locations

▪ Procedures for cleaning and refurnishing the areas for 

separation purposes, and step-by-step procedures for staff to 

follow to start the exhaust fan, close the return air dampers, and 

test for negative pressure

▪ Measures for preparing the areas for back-to-back occupants 

requiring separation

▪ Procedures for cleaning and returning the areas to normal use 

after the need for respiratory separation has passed

○ Operate the new systems as designed and according to the written 

plan. When in use, the respiratory separation area should be visually 

tested with smoke tubes or flutter strips daily to ensure negative 

pressure is being maintained while the room is occupied for separation. 

When the room is being used for normal purposes, it should be tested 

monthly to ensure proper operation in the event they would be needed 
Health Hazard Evaluation Report 2012-0155-3180 Page 19

for respiratory separation. The results of all pressure testing should be 

documented.

5. Develop and implement an OSHA respiratory protection program in accordance 

with 29 CFR 1910.134. To meet the OSHA requirements, you must:

● Designate a program administrator who is qualified by appropriate training 

or experience to administer or oversee the program and conduct the required 

program evaluations.

● Provide respirators, training, and medical evaluations at no cost to employees 

or staff required to wear respirators on the job.

● Develop a written program with worksite-specific procedures when respirators 

are necessary or required by the employer. The written respiratory protection 

program needs to include:

○ Respirator types and proper respirator selection

○ Required medical evaluations for employees prior to respirator use

○ Procedures for initial and annual respirator fit testing

○ Instructions for proper respirator use

○ Information on appropriate respirator maintenance and care

○ Initial and yearly training requirements for respirator users 

○ Procedures for evaluating the effectiveness of the respiratory 

protection program

● Update the respiratory protection program as necessary to reflect changes in 

workplace conditions that affect respirator use.

6. Repair all existing bathroom exhaust fans or install new ones. Ensure that air is 

being exhausted from each bathroom and shower facility and that each area is under 

negative pressure, in accordance with the 2010 Florida Building Code and ASHRAE 

requirements. Ensure that all exhaust air from bathrooms and shower facilities is 

exhausted directly outside and that no return air from bathrooms is recirculated back to 

an AHU or entrained in the outdoor air entering any current or future AHU.

7. Install additional safety features on the existing in-duct UV systems to meet CDC 

recommendations. In addition to the labels currently on the outside of the AHUs, the 

following should be done:

● Install a viewport or window in the AHU so maintenance personnel can see 

when the lamps are on or burned out.

● Install a safety switch on the AHU access panel that automatically powers 

down the lamps when the access panels are removed.
Page 20 Health Hazard Evaluation Report 2012-0155-3180

● Ensure that nonmetallic surfaces exposed to direct or reflected UV energy 

are properly shielded with foil tape or metal guards to prevent material 

degradation.

8. After all of the ventilation systems are updated and functioning properly, develop 

a comprehensive, written HVAC O&M plan. The O&M Plan should include:

● Preventive maintenance schedules and all regularly scheduled maintenance 

tasks (filter changes, fan belt inspections, UV lamp changes, etc.) and who is 

responsible for conducting each task

● Written procedures for each maintenance task to ensure the work is done 

properly each time, regardless of who performs the work

● Training requirements for maintenance staff

● A method for logging maintenance activities for each AHU

● A method for updating or revising the O&M Plan as procedures or systems 

change

Outline of Future NIOSH Involvement

This report will serve to close out NIOSH Technical Assistance at New Life Inn. However, 

we understand that the work outlined in the recommendations above will take several months 

to complete and will represent a significant investment of time and financial resources. As 

the work proceeds, NIOSH could assist by:

● Reviewing any Requests for Proposal developed to initiate the bidding process

● Reviewing any bids received in response to Requests for Proposals for 

technical content

● Providing technical assistance related to any environmental control strategies

It is not necessary for NIOSH to be on-site during any ventilation renovations. Yet, as projects are initiated, we can assist you by reviewing:

● Proposed modification strategies for outdoor air introduction or respiratory 

separation area designs

● Preliminary design schematics or equipment selection documents 

● Air flow testing and balancing reports

● Final project documents, including as-built drawings, sequences of operations, 

and proper equipment set points

Once the renovations are complete, if additional NIOSH assistance is desired or warranted, 

the request for technical assistance can be reopened.
Health Hazard Evaluation Report 2012-0155-3180 Page 21

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in a shelter for homeless men: A description of its evolution and control. Am Rev Respir 

Dis 143:257-261.

Slutkin G [1986]. Management of tuberculosis in urban homeless indigents. Public Health 

Rep 101(5):481-485.
Health Hazard Evaluation Report 2012-0155-3180 Page 23 Table 1. General air-handling unit (AHU) information NIOSH AHU Identifier Physical Location of AHU (floor/building) Main Location Served by AHU (floor/building)A AHU ManufacturerB AHU Model NumberB Proper Filter Configuration in AHUC,D Actual Filter Configuration in AHUB,D,E AHU-1 Central Mechanical Room (1st floor/main building) Registration/Lobby, Laundry Area (1st floor/ main building) Goodman AR61-1 (1) 20 × 24 × 1 *NoneF AHU-2 Southeast Corner Mechanical Room (1st floor/main building) Kitchen, Kitchen Office (1st floor/main building) International Comfort Products FSM2X6000A (1) 20 × 24 x 1 (1) 20 × 24 × 1 AHU-3G Southeast Corner Mechanical Room (1st floor/main building) Dining/Assembly Area (1st floor/main building) Carrier 40RUQA08A2A6A0A0A0 (4) 16 × 24 × 2 *(4) 20 × 25 × 2 AHU-4 West Mechanical Room (2nd floor/main building) All Transition Rooms (2nd floor/main building) Trane TWE036C14FB0 (1) 20 × 20 × 1 *(1) 20 × 25 × 1 AHU-5 West Mechanical Room (2nd floor/main building) All Administration Of- fices/Areas (2nd floor/ main building) York NAMB-FD20AC UnknownH (1) 20 × 22 × 1H AHU-6 Southeast Corner Mechanical Room (2nd floor/main building) Work Program Sleep- ing Area (2nd floor/main building) International Comfort Products FSM2X6000A (1) 22 × 24 × 1 *(1) 20 × 24 × 1 AHU-7 Central Mechanical Room (3rd floor/main building) Lifebuilders Program Sleeping Area (3rd floor/ main building) Trane TWE090D300AA (3) 16 × 25 × 1 (3) 16 × 25 × 1 AHU-8 Southeast Corner Mechanical Room (3rd floor/main building) Overnight Sleeping Area (3rd floor/main building) Carrier 40RMQ008--B611HC (4) 16 × 24 × 2 (4) 16 × 24 × 2 AHU-9 Mechanical Room (annex) All Locations (annex) Trane TWE120A100EL (4) 16 × 25 × 1 *(4) 20 × 24 × 1 A May not represent all locations served by the AHU B Information collected during visual inspection of AHU C Information gathered from product data specific to each AHU model published by respective AHU manufacturer D Value in parenthesis represents the number of filters; dimensions are width × height × depth in units of inches E Entries preceded by an asterisk (*) represent actual filter configurations that differ from published proper filter configurations. Differences could be due to incorrect filter size(s) being installed or because the AHU manufacturer modified the AHU model size/filter recommendation as the product was updated.

F No filter was installed in the AHU during the NIOSH visit. One 25 × 25 × 2 filter was installed in the door leading into the mechanical room housing AHU-1.G This AHU is equipped with a Fresh-Aire in-duct UV system that may provide some inactivation of airborne pathogens as they pass through the irradiated zone. The  effectiveness of the UV system could not be determined during the NIOSH visit. H Manufacturer product literature for this AHU could not be found online or through a York dealer. Thus, the proper filter configuration could not be determined.

Tables
Page 24 Health Hazard Evaluation Report 2012-0155-3180

Table 2. Applicable outdoor air supply flow rates, minimum exhaust air flow rates, 

and default occupancy densities from the 2010 Florida Building Code and ASHRAE 

Standard 62.1-2010A

Occupancy Category

People Outdoor

Air Flow Rate

(cfm/person)B

Area Outdoor

Air Flow Rate

(cfm/ft2)C

Minimum Exhaust

Air Flow RateD

Default 

Occupant 

Density

(#/1000 ft2)E

Barracks/Dormitory Sleeping Areas 5 0.06 — 20

Bedrooms/Living Rooms 5 0.06 — 10

Office Spaces 5 0.06 — 5

Conference Rooms 5 0.06 — 50

Multipurpose Assembly Spaces 5 0.06 — 120

Reception Areas 5 0.06 — 30

Break RoomsF 5F 0.12F — 50F

Central Laundry RoomsF 5F 0.12F — 10F

Occupiable Dry Storage RoomsF 5F 0.06F — 2F

Occupiable Liquid/Gel Storage RoomsF 5F 0.12F — 2F

Unoccupiable Storage RoomsG — 0.12G — —

Lobbies/Prefunction Spaces 7.5 0.06 — 30

Lecture Classrooms 7.5 0.06 — 65

Computer Labs 10 0.12 — 25

Dining Rooms 7.5 0.18 — 70

Central Kitchens 7.5F 0.12F 0.7 cfm/ft2 C 70

Public Bathrooms — — 50 or 70 cfm/toilet 

and/or urinalH —

Private Bathrooms — — 25 or 50 cfmI —

Shower RoomsG — — 20 or 50 cfm/

shower headG,J —

A Requirements published in: 2010 Florida Building Code: Mechanical (Chapter 4, Ventilation). International Code 

 Council, Inc., Country Club Hills, IL (2011) and American National Standards Institute (ANSI)/American Society of 

 Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Ventilation for Acceptable Indoor Air Quality, 

 Standard 62.1-2010. ASHRAE, Atlanta, GA (2010). In nearly all cases, the 2010 Florida Building Code has adopted ventila 

 tion recommendations directly from ASHRAE Standard 62.1-2010.

B

 cfm/person = cubic feet per minute (also commonly shown as ft3/min) per person typically in the occupied space C cfm/ft2

 = cubic feet per minute (also commonly shown as ft3/min) per square feet of occupied space D Mechanical exhaust should be released directly outdoors at least 25 feet away from air intakes. Recirculation of exhaust 

 air back into the building should be avoided.

E

 #/1000ft2 = number of people per 1000 square feet of occupied space. These values are typical occupant densities in 

 spaces that are useful for building/HVAC system design. If actual occupant densities are known, they should be used 

 instead of these default values.

F

 Requirements are only published in ASHRAE Standard 62.1-2010. No directly corresponding values appear in the 2010 

 Florida Building Code. G Requirements are only published in the 2010 Florida Building Code. No directly corresponding values appear in ASHRAE 

 Standard 62.1-2010.

H Provide the higher rate when periods of heavy use are expected to occur (e.g. prior to guests leaving in the morning). If 

 periods of heavy use are not anticipated, the lower rate may be used.

I

 These rates are for bathrooms intended for use by one person at a time. If exhaust fans are operated continuously, the 

 lower rate may be used. If exhaust fans are operated intermittently (e.g., fans activated by a light switch), the higher 

 rate should be used.

J

 If exhaust fans are operated continuously, the lower rate may be used. If exhaust fans are operated intermittently (e.g., 

 fans activated by a light switch), the higher rate should be used.
Health Hazard Evaluation Report 2012-0155-3180 Page 25 Table 3. Total air delivered by ventilation systems, occupant densities, and recommended outdoor air flow SpaceA AHU Serving Space Return Flow from Space (cfm)B Supply Flow into Space (cfm)B Approximate Area of Space (ft2)C Typical Oc- cupants in SpaceD Occupant Density (#/1000 ft2)D,E,F Recommended Outdoor Air Flow (cfm)B,G 1st Floor – Main Building Registration/Lobby AHU-1 DoorH 790 620 8 13 77.2 Registration Office AHU-1 DoorH 100 85 1 *12 10.1 Laundry Area AHU-1 DoorH 400 450 1 2 59.0 Kitchen AHU-2 0I,J 490 765 4 5 121.8 Kitchen Office AHU-2 190 95 95 1 *11 10.7 Dining/Assembly Area AHU-3 2130 2865 1755 60 34 405.3/765.9K 2nd Floor – Main Building Transition Room #1L AHU-4 140 340 300 2 7 28.0 Transition Room #2L AHU-4 155 < 30I,M 300 2 7 28.0 Transition Room #3L AHU-4 70 300 300 2 7 28.0 Shelter Administrator’s Office AHU-5 NoneN 185 145 1 *7 13.7 Additional Glass Office AHU-5 NoneN 170 150 1 *7 14.0 Reception Area AHU-5 DoorH 285 215 2 9 22.9 Conference Area AHU-5 DoorH 145 275 4 15 36.5 First Conference Area Office AHU-5 DoorH 90 115 1 *9 11.9 Second Conference Area Office AHU-5 DoorH 140 115 1 *9 11.9 Large Corner Office/Storage Area AHU-5 DoorH 200 215 1 5 17.9 Large Storage Area AHU-5 DoorH 75 130 0 0 15.6 Small Storage Area AHU-5 DoorH 45 55 0 0 6.6 Men’s Room Off Conference Area N/AO < 30I NoneP 25 N/AQ N/AQ N/AQ Women’s Room Off Conference Area N/AO < 30I NoneP 25 N/AQ N/AQ N/AQ Work Program Sleeping Area AHU-6 295 955 1355 24 18 201.3 Work Program Bathroom/Showers N/AO 0I NoneP 255 N/AQ N/AQ N/AQ
Page 26 Health Hazard Evaluation Report 2012-0155-3180

Table 3 (continued). Total air delivered by ventilation systems, occupant densities, and recommended outdoor air flowSpaceA

AHU 

Serving 

Space

Return Flow 

from Space

(cfm)B

Supply 

Flow into 

Space

(cfm)B

Approximate 

Area of Space

(ft2

)C

Typical Occupants in 

SpaceD

Occupant Density

(#/1000 ft2

)D,E,F

Recommended Outdoor Air Flow

(cfm)B,G

3rd Floor – Main BuildingLifeBuilders Program Sleeping Area AHU-7 1230R,S 1610 2475 60 *24 448.5LifeBuilders Program Bathroom/Showers N/AO 0I NoneP 280 N/AQ N/AQ N/AQOvernight Sleeping Area AHU-8 1200S 1205 2205 67 *30 467.3Overnight Bathroom/Showers N/AO 0I NoneP 190 N/AQ N/AQ N/AQAnnexEntrance/Registration/Clothing Storage AHU-9 WallT 300 585 8 14 75.1Seating/Gathering Area AHU-9 WallT 1160 790 70 89 397.4

A May not represent all locations served by the AHUB cfm = cubic feet per minute (also commonly shown as ft3/min) C ft2 = square feet D Occupant numbers estimated by visual observation during NIOSH visitE #/1000 ft2 = number of occupants per 1000 ft2 of occupied floor space. Calculated by dividing the number of typical occupants in the space by the approximate area of the space  and multiplying by 1000.F Entries preceded by an asterisk (*) represent spaces where the actual occupant density likely exceeds the default occupant density presented in Table 2.G Calculated based on recommendations published in: American National Standards Institute (ANSI)/American Society of Heating, Refrigerating and Air-Conditioning Engineers  (ASHRAE). Ventilation for Acceptable Indoor Air Quality, Standard 62.1-2010. ASHRAE, Atlanta, GA (2010) and the 2010 Florida Building Code: Mechanical (Chapter 4, Ventilation).  International Code Council, Inc., Country Club Hills, IL (2011). In nearly all cases, the 2010 Florida Building Code has adopted ventilation recommendations directly from ASHRAE  Standard 62.1-2010.H There were no return grilles. All air returning to the AHU passed through a grille in the door, cracks around the closed door, and various openings/leaks within the mechanical  room structure. These air flows could not be measured accurately during the NIOSH visit.I A TSI Accubalance Plus, Model 8373, was used to determine air flow measurements. The instrument is unable to accurately read volumetric air flow rates less than 30 cfm.  Reading could be anywhere between 0 and 30 cfm. In these cases, ventilation fog was used to visually determine if any air was flowing through the vent/grille. When there was  visual confirmation of air flow, the result was reported as < 30 cfm. When air flow could not be verified visually, the result was reported as 0 cfm.J Does not include air pulled from the area by kitchen exhaust hoods. Air flow measurements through exhaust hoods were not taken.K ASHRAE Standard 62.1-2010 and the 2010 Florida Building Code: Mechanical (Chapter 4, Ventilation) provide separate outdoor air recommendations for assembly spaces and  dining rooms. Both numbers are reported here (assembly space/dining area).L Transition rooms were equipped with their own private bathrooms, but there were no separate bathroom exhaust systems. ASHRAE Standard 62.1-2010 and the 2010 Florida  Building Code: Mechanical (Chapter 4, Ventilation) specifies 25 cfm of exhaust air per toilet. This exhaust air may be made up entirely of transfer air from adjacent spaces (i.e., no  direct supply air to the space is required) and only a maximum of 10% of the exhaust air is permitted to be recycled.M Cardboard was covering the supply vent. The cardboard was not removed during the NIOSH visit.N There was/were no return grille(s) in this space. Only supply vent(s) was/were present.O N/A = not applicable. Ventilation systems were properly designed to not supply air to this space.P There was/were no supply vent(s) in this space. Only return grille(s) was/were present.Q N/A = not applicable. Neither ASHRAE Standard 62.1-2010 nor the 2010 Florida Building Code include outdoor air recommendations for restrooms, bathrooms, and shower facili ties. Instead, for public bathrooms, the recommendation is 50 cfm of exhaust from the space per toilet or urinal when periods of heavy use are not expected. ASHRAE 62.1-2010 does not specifically address ventilation for showers. However, the 2010 Florida Building Code: Mechanical (Chapter 4, Ventilation) specifies 50 cfm of exhaust air from the  space per shower head when the exhaust system is designed to operate intermittently (e.g., exhaust fan connected to light switch) or 20 cfm per shower head for exhaust  systems designed to operate continuously. Water closet and shower exhaust may be made up entirely of transfer air from adjacent spaces (i.e., no direct supply air to the space  is required) and only a maximum of 10% of the exhaust air is permitted to be recycled.R Includes flow through the grille in the door into the mechanical room housing AHU-7S Return grilles in this area were caked with dust and dirt. They should be cleaned periodically.T There were no return grilles. All return air passed through holes in the wall and around the door into the mechanical room housing AHU-9. These air flows could not be mea sured accurately during the NIOSH visit
Health Hazard Evaluation Report 2012-0155-3180 Page 27

Table 4. ASHRAE indoor relative humidity and temperature recommendationsA

Relative Humidity Winter TemperaturesB Summer TemperaturesB

30%C 69.5°F to 77.0°F 75.5°F to 81.5°F

40% 69.0°F to 76.5°F 75.5°F to 81.0°F

50%D 68.5°F to 76.0°F 75.0°F to 80.5°F

A Adapted from: American National Standards Institute (ANSI)/American Society of Heating, Refrigerating and Air- 

 Conditioning Engineers (ASHRAE). Thermal Environmental Conditions for Human Occupancy, Standard 55-2010. `

 ASHRAE, Atlanta, GA. (2010)

B Applies to occupants wearing typical summer and winter clothing, with a sedentary to light activity level

C Humidity levels below 30% may cause irritated mucus membranes, dry eyes, and sinus discomfort.

D The U.S. Environmental Protection Agency recommends maintaining indoor relative humidity below 60% and ideally in 

 a range from 30% to 50% to prevent mold growth.
Page 28 Health Hazard Evaluation Report 2012-0155-3180

Figure 1. AHU-1 in the central mechanical room on the first floor of the shelter. The 

photograph shows standing water and apparent microbial growth due to condensate 

from the AHU leaking onto the floor of the mechanical room.

Figures
Health Hazard Evaluation Report 2012-0155-3180 Page 29

Figure 2. AHU-6 in the southeast corner mechanical room on the second floor of the 

shelter. The photograph shows condensate and debris in the return air plenum under the 

AHU.
Page 30 Health Hazard Evaluation Report 2012-0155-3180

Figure 3. AHU-8 in the southeast corner mechanical room on the third floor of the shelter. 

The photograph shows a drain pan overflowing with condensate, which is covering the 

floor of the mechanical room.
Health Hazard Evaluation Report 2012-0155-3180 Page 31

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Page 32 Health Hazard Evaluation Report 2012-0155-3180

The Health Hazard Evaluation Program investigates possible health hazards in the 

workplace under the authority of Section 20(a)(6) of the Occupational Safety and 

Health Act of 1970, 29 U.S.C. 669(a)(6). The Health Hazard Evaluation Program also 

provides, upon request, technical assistance to federal, state, and local agencies to control 

occupational health hazards and to prevent occupational illness and disease. Regulations 

guiding the Program can be found in Title 42, Code of Federal Regulations, Part 85; 

Requests for Health Hazard Evaluations (42 CFR 85).

Acknowledgments

This report was prepared by Stephen B. Martin, Jr., R. Brent Lawrence, and Michael C. 

Beaty of the Field Studies Branch (FSB), Division of Respiratory Disease Studies (DRDS) 

and Kenneth R. Mead of the Engineering and Physical Hazards Branch, Division of Applied 

Research and Technology. Desktop publishing was performed by Tia McClelland (FSB/

DRDS).

Availability of Report

Copies of this report have been sent to representatives from City Rescue Mission–New Life 

Inn, DCHD, the Florida Department of Health, CDC/NCHHSTP/DTBE, and the OSHA

Regional Office. This report is not copyrighted and may be freely reproduced. 

This report is available at http://www.cdc.gov/niosh/hhe/reports/pdfs/2012-0155-3180.pdf.

Recommended citation for this report:

NIOSH [2013]. Health hazard evaluation report: Evaluation of 

Environmental Controls at a Homeless Shelter (City Rescue Mission–New 

Life Inn) Associated with a Tuberculosis Outbreak – Florida. By Martin, Jr. 

SB, Mead KR, Lawrence RB, Beaty MC. Morgantown, WV: U.S. Department 

of Health and Human Services, Centers for Disease Control and 

Prevention, National Institute for Occupational Safety and Health, NIOSH 

Report No. 2012-0155-3180.
To receive documents or other information about

occupational safety and health topics, contact NIOSH

Telephone: 1-800-CDC-INFO (1-800-232-4636)

TTY: 1-888-232-6348

email: cdcinfo@cdc.gov

or visit the NIOSH website at http://www.cdc.gov/niosh

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