# Presentation: 279773

## Engineering Controls Related to Tuberculosis Prevention

- Insert name of presenter
- (Should be someone familiar with facility ventilation systems)

**Notes:**
Note:  This slide is the title slide of the presentation.  The presenter should insert their name, title, etc. 

Note:  Presenters should not read the speaker’s notes verbatim for this presentation.  The notes are intended only to clarify specific topics that should be discussed.  Presenters are encouraged to base their presentation on their personal experience and training. 

This presentation consists of 15 slides and is estimated to last 30 minutes (2 minutes per slide).   

## Facility Specific Administrative Procedures

- Admission screening designed to identify suspected or known infectious tuberculosis
- Transport of suspected or known infectious tuberculosis patients within medical center minimizes path of travel (including within surgical suite) and exposure of other patients, visitors, and employees
- Assign tuberculosis patients to appropriate (properly operating) isolation rooms

**Notes:**
Each healthcare facility is required by OSHA (the Occupational Safety and Health Administration) to provide a safe and healthful workplace for its employees.  As healthcare providers our foremost concern is the health of the patient.  These two concerns are efficiently addressed by the complete implementation of an effective tuberculosis prevention program.  Such programs must greet suspected or known infectious tuberculosis patients at the door of the medical center and continue with them until they are no longer infectious.

Effective tuberculosis programs include both administrative, engineering, and personal protective equipment aspects or controls.  Administrative procedures include admission screening, access restriction, etc.  This slide summarizes facility specific administrative procedures that are based on requirements that can be traced to engineering controls.  Engineering controls include negative pressure isolation rooms, effective ventilation in waiting areas, and maintenance of these controls.  Personal protective equipment includes respirator use, latex gloves, etc.  Each facility must address these tuberculosis prevention controls during training and all employees that are involved must be familiar with these controls.  Healthcare providers must know which rooms in the facility are isolation rooms, which of the isolation rooms are operational, which are scheduled for maintenance or repair, and must follow appropriate procedures to minimize the exposure of employees and other patients. 

## Role of Healthcare Providers

- Keep doors closed (unless entering or exiting)
- Keep windows closed
- Provide for comfort of patient
- Periodically monitor positive/negative controls and room pressure monitors, if present
- Notify engineering if isolation room does not appear to be operating within design parameters

**Notes:**
Slide 2 lists responsibilities of healthcare providers as they relate to suspected or known infectious tuberculosis patients in isolation rooms.  Isolation rooms are specifically designed to protect employees and patients in other parts of the medical center.  However, these controls are only effective if healthcare providers use the controls properly (e.g., keep doors (when not in use) and windows closed) and notify appropriate personnel when they suspect that the engineering controls are not working properly or as designed.

Engineering must be notified that a suspected or known infectious tuberculosis patient has been assigned an isolation room, so that required monitoring can be performed.  OSHA (under their enforcement procedures -- CPL 2.106) states that isolation rooms should be checked daily for negative pressure while being used for TB isolation.  Daily monitoring should continue until tuberculosis is excluded as a diagnosis or until the patient is no longer infectious.

## Isolation Rooms

- Reduce the occupational risks
- Prevent the spread of disease or infection to patients
- Negative pressure isolation rooms are required for suspected or known infectious tuberculosis patients

**Notes:**
Isolation rooms are compromised when the rooms are not maintained within design parameters, healthcare providers operate outside the limitations of the isolation rooms, and patients, visitors, and staff do not follow appropriate procedures.  Isolation room design may vary (e.g., some may use HEPA filtration and others may not have anterooms) and have different use operational protocols (Details concerning the operational protocols used in these two examples is likely to detailed for this audience.  But they can be found in OSHA Enforcement Procedures CPL 2.106 paragraph L. 1. e. 5. under Engineering Controls.
This slide lists several reasons that isolation rooms are of particular importance to healthcare providers:
	- Reduce the risk to health care works
	- Prevent the spread of disease or infection to patients
Both are of critical importance.  Just as we would insist that a patient take the proper medication, healthcare providers and engineering personnel must work together to assure that the proper isolation is provided.

The third item listed - negative pressure isolation rooms are required for suspected or known infectious tuberculosis patients - is recognized by OSHA, CDC, and VA as necessary to assure that treatment is improved and that tuberculosis is prevented.  With the advent of large modern and complex medical buildings control of airborne hazards have created new challenges to engineers.   

## Isolation Room Design

- CDC specifies engineering design requirements for TB isolation rooms:
- Negative pressure must be maintained
- Unidirectional airflow (Into room)
- Proper air change rate (6 times per hour in existing facilities 12 times per hour in new facilities)
- Periodic maintenance and evaluation are required (Engineering responsibility)

**Notes:**
Isolation rooms don’t just happen, and they don’t operate indefinitely without proper maintenance, repair, and monitoring.  Engineering design requirements are described in VA guidance and by CDC in Supplement 3: Engineering Controls of the “Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health-care Facilities, 1994; MMWR Volume 43/No. RR-13 dated October 28, 1994.

This presentation is not intended to make healthcare providers engineers capable of designing and maintaining isolation rooms.  However, each healthcare provider for suspected or known infectious tuberculosis patients must be familiar with the role of engineering controls in providing proper isolation.  We have previously discussed the healthcare provider’s administrative role required to assure that engineering controls are effective.  This portion of our discussion will address basic engineering design parameters that are required to assure effective isolation.  Healthcare providers should be generally knowledgeable with engineering control design parameters, so that they can recognize when proper isolation is not being provided and either the patient or employees may be at risk.  Healthcare providers should be aware that they are not the only safeguard present to assure that engineering controls are operational.  Engineering staffs and safety offices are responsible to perform periodic monitoring and evaluation and for the proper operation of these systems.

## Negative Pressure Isolation Rooms

- Air moving into room (smoke goes into room)
- Surrounding area isolated from contamination by patient
- Ventilation system exhausts air to the outside or HEPA filtered (no recirculation unless HEPA filtered)
- Patient room negative to ante room (if used), ante room negative to corridor

**Notes:**
Unidirectional airflow (slide 5) refers to the fact that air enters the room (from surrounding areas -- i.e., from under the door, through leaks around the windows, etc.) and is exhausted from the room ( e.g., air conditioning and air outlets/exhaust duct(s)).  Air travels from surrounding areas into the room; air does not travel from the room into surrounding areas.  Isolation rooms are NOT air tight.  They are not sealed with plastic to keep air in or out, but the ventilation system exhausts the air from the room.  Unidirectional airflow assures that the surrounding areas are not contaminated with the illness or disease of the patient. 

Negative pressure refers to the fact that the isolation room is under negative pressure relative to the surrounding areas.  Negative pressure can be tested by the use of smoke tubes.  (If the presenter has a smoke tube, a brief demonstration could be inserted to show attendees how the smoke tube is used.)  If the smoke moves into the isolation room, it is under negative pressure.  If the smoke moves out of the isolation room, it is under positive pressure and should not be used for suspected or known infectious tuberculosis patients.

All air from TB isolation rooms is required to be exhausted to the outside. Air within negative pressure isolation rooms cannot be recirculated except if it is HEPA filtered (filtered air ducts should be labeled according to OSHA).  Ideally air should be directed outside where sunlight can kill TB.         

## Positive Pressure Isolation Rooms

- Not permitted for airborne infectious diseases
- Air moving out of room (smoke goes out)
- Patients isolated from surrounding area contamination
- Patient room positive to ante room (if used), ante room positive or neutral to corridor

**Notes:**
Positive pressure refers to the fact that the isolation room is under positive pressure to the surrounding areas.  If smoke moves away from the isolation room, it is under positive pressure.  Positive pressure isolation rooms must not be used for infectious disease isolation, because the surrounding areas would be contaminated with the patient’s illness or disease.  Positive pressure isolation rooms are used when the patient must be protected from contaminants that may be present in the surrounding areas.  HIV patients, bone marrow transplant patients, etc. should be assigned to positive pressure isolation rooms.
NOTE:  Some facilities have the capability of utilizing the same room for either positive or negative pressure.  typically a switch will be provided to select the appropriate mode of operation.

## Isolation Room Uses

- Negative Pressure
- Tuberculosis
- Chickenpox (varicella)
- Herpes zoster
- Measles (rubeola)

- Positive Pressure
- Bone Marrow Transplant
- AIDS

**Notes:**
Note:  The presenter may want to add to each of the lists, particularly if there are other issues of interest at the facility or if the presenter intends to use examples of infectious diseases that are not listed, but require the use of negative pressure isolation rooms. 

The left column of this slide lists airborne infectious diseases that are required to be assigned to negative pressure isolation rooms.  The right column lists patients that should be assigned to positive pressure isolation rooms.  These lists are not complete.  

## Monitoring

- Methods
- Smoke tubes
- Duct mounted instruments
- Gauges
- Alarms
- Automated systems

- Frequency
- Daily (Active TB)
- Monthly
- Quarterly
- Annually

**Notes:**
Note:  The presenter should clearly state that the VA does not recommend any particular manufacturer or any particular instruments that may be discussed as part of this presentation.

Methods:  The smoke tube method to monitor negative and positive pressure has been discussed previously.  Other methods of monitoring negative pressure are through the use of duct mounted instruments, gauges, alarms, and automated systems.  Specific methods used at the facility will be discussed as part of slide 14; however, manufacturer’s literature concerning instruments used to monitor negative pressure is included in the handout materials. This literature is included so that the attendees can become familiar with the instruments available.  
Frequency:  OSHA states (CPL 2.106) that monitoring be performed daily when suspected or known infectious tuberculosis patients are assigned to negative pressure isolation rooms.  

ANSI and NFPA standards concerning ventilation systems have periodic monitoring requirements that will be researched and discussed as part of this slide.   

## Specific Medical Center Areas

- Patient rooms
- Private Bathrooms
- 6 air changes per hour
- ICU
- Return air systems must have HEPA filters
- 8 air changes per hour
- 25% outside air

- Ambulatory care and associated waiting areas (high risk)
- Designed and maintained to reduce risk of tuberculosis transmission
- 10 air changes per hour and should pass through a HEPA filter
- Special procedures
- 12 air changes per hour

**Notes:**
This slide lists several medical center areas and briefly summarizes the  engineering control requirements for each area.  The engineering control requirements for specialized areas within the medical center vary significantly.  Facility management must assure that engineering staffs provide service within the design requirements, that healthcare providers are aware of the clinical limitations of the designs, and that these areas are used in accordance with the design at all times.

ICU - Intensive Care Unit
Ambulatory Care - Hospital-based, satellite, and independent out patient	clinics.  NOTE:  Many ambulatory care requirements establish the need for engineering controls similar to TB treatment rooms with a minimum air change of 6 per hour for existing and 12 per hour for new facilities.

## Special Procedures

- Potential Aerosol Producing Procedures
- Sputum Induction
- Aerosol Treatments
- Cough or Aerosol-generating
- Aerosolized Pentamidine
- Pulmonary Function Treatment Rooms and  Laboratories
- Bronchoscopy Areas

- Requirements
- 12 air changes per hour
- Exhausted outside (no recirculation)
- Cannot be done in patient rooms unless CDC requirements are met (12 air changes, etc.)
- Requirements apply if booths are used

**Notes:**
The left column of this slide lists tuberculosis-related medical procedures or specialized areas within the medical center that require special engineering controls to assure the safety and health of patients and employees.  These procedures can only be done in patient rooms, if the room meets all of the requirements for the procedure or area.

The right column of the slide lists some of the specific requirements for the procedures or areas.  Notice the increased number of air changes required from the number required for negative pressure isolation rooms (6 air changes).  Some facilities can perform these procedures in patient isolation rooms and some cannot, depending upon the number of air changes provided.  Clinical and engineering personnel must work together to determine where these procedures can be performed safely.

Additionally, if a booth or chamber is used to perform these procedures, the booth or chamber must meet the requirements specified for the procedure.     

## Coordination Required

- Engineering
- Locations of negative pressure isolation rooms
- Operational status
- Schedule of repair or maintenance that may impact isolation rooms
- Room Monitoring

- Healthcare Providers
- Assign patients to appropriate isolation rooms
- Keep doors (unless being used) and windows closed
- Notify engineering when controls do not appear effective

**Notes:**
As with almost everything else in a medical center, the best administrative or engineering controls are only effective when communicated, implemented, and maintained properly.  Engineering staff and healthcare providers must work together to assure that each can perform their responsibilities.   If a suspected or known infectious tuberculosis patient is assigned to a room that is not providing adequate negative pressure, another patient or employee may be exposed to tuberculosis.

Limitations of engineering controls must clearly communicated to healthcare providers.  The left column lists some of the information that engineering staff must communicate to healthcare providers - the location of negative pressure isolation rooms, the operational status of those rooms, when maintenance or repair may restrict the use of the isolation rooms, etc.

Healthcare providers must support engineering staff in their efforts to provide and maintain isolation room systems and must notify engineering personnel when those systems do not appear to be operating properly.  That does not mean that healthcare providers should be using smoke tubes to determine if the system is operating properly, but it does mean that they should call engineering when they notice that the ventilation system is not working in the isolation room.  Healthcare providers must follow appropriate facility procedures, such as assigning patients to an appropriate isolation room, keeping doors  closed (when not entering or exiting), keeping windows closed in isolation rooms, and transporting suspected or known infectious tuberculosis patients through the medical center, so that the path of travel and the exposure of other patients, visitors, and employees is minimized.  

## Facility Specific Isolation Rooms

- Negative Pressure Isolation Rooms
- (Insert locations of negative pressure isolation rooms)
- Positive Pressure Isolation Rooms
- (Insert locations of positive pressure isolation rooms)

**Notes:**
Note:  This slide must be revised by the presenter.  If the presenter’s facility does not have any isolation rooms in one of the categories listed, that should be stated.  If the presenter’s facility does not have either negative or positive isolation rooms, this slide can be deleted.

The presenter should list those facility locations that can be used as patient rooms for suspected or known infectious tuberculosis patients under the “Negative Pressure Isolation Rooms” heading.  Presenters should clearly state that this the information listed applies only to the VA medical center, and that attendees from outside the VA should be able to obtain similar information specific to their facility.

Under the heading “Positive Pressure Isolation Rooms” the presenter should list those facility locations that meet the requirements for positive pressure isolation rooms.     

## Engineering Considerations

- Room Pressure Monitors
- (Insert facility specific
- information)

- Periodic Monitoring
- (Insert facility specific
- information)
- Maintenance
- (Insert facility specific
- information)

**Notes:**
Note:  This slide must be revised by the presenter.  Presenters should keep in mind that some of the attendees may not work at the VA medical center, and should clearly state that all facilities may not have identical room pressure monitors or may not have any monitor at all, may not perform identical monitoring, or may not perform identical maintenance. 

Room Pressure Monitors - The presenter should revise this section of the slide so that the specific room pressure monitors used at the facility are discussed.  If none are used, the slide should state that none are used.  Presenters should be careful to provide attendees only that information necessary to perform their jobs.  If pictures or drawings of the room pressure monitors used at the presenter’s facility are available, it is recommended that the presenter use the pictures or drawings during this portion of the presentation.  If specific settings (or a range of settings) are to be maintained to assure a negative pressure is provided, the presenter should discuss the acceptable setting (or range) and the procedures to follow if the setting (or range) is not acceptable.

Periodic Monitoring - The presenter should revise this section of the slide so that the specific monitoring performed at the facility is discussed.  Monitoring that is performed (daily, monthly, quarterly, or annually) should be briefly discussed. 

Maintenance -  The presenter should revise this section of the slide so that periodic maintenance performed at the facility is briefly discussed. 

## References

- CDC Guideline for Isolation Precautions in Hospitals
- CDC Guidelines for Preventing the Transmission of Tuberculosis in Health-Care Facilities, MMWR 1994; 43(RR-13):1-132
- Health Resources and Services Administration, Guidelines for Construction and Equipment of Hospital and Medical Facilities, HHS, PHS Publication (HRSA) 84-14500
- American Institute of Architects, Guidelines for Construction and Equipment of Hospital and Medical Facilities, 1993
- ASHRAE 1991 Application Handbook
- VA Consulting Support Office, Office of Facility Management

**Notes:**
This slide lists the references used to develop this presentation, and also serves as a list of additional reading sources for attendees, who want to learn more about specific topics discussed.
VA support offices include:
Consulting Support Office, Office of Facility Management, VA Headquarters (202) 565-6396
Office of OSH (00S1) (202) 273-9743
Headquarters Network Office (10N) (202) 273-5863