Position Paper No. 1 on ANSI/ASHRAE/ASHE Standard 170-2017 Ventilation Healthcare Facilities [Safe Haven or Area of Refuge for Healthworkers and Medical Doctors]

ANSI/ASHRAE/ASHE Standard 170-2008

Ventilation of Health Care FacilitieSafe [Haven or Area of Refuge fot Healthworkers and Medical Doctors]

I. Introduction

This paper seeks guidance from “ANSI/ASHRAE/ASHE Standard 170-20117” by using its written standard sections and paragraphs as reference to the methodologies that would result to the  formulation of an addendum or new sections to prevent transmission of virus in air in the hospital. Our proposal was to provide a standard for a “safe haven or area of refuge” for health workers in a hospital.


To identify the problem and provide countermeasure to mitigate virus transmission in a hospital, to prevent the spread of infection to patient and health workers. To achieve this purpose ANSI/ASHRAE/ASHE Standard 170-2017 sections and paragraphs relative to the purpose of this report will be reviewed about hospital best practices. The result of these procedures and recommendations will be studied by other sectoral groups interested to improve the hospital environmental protection.

An overview of the methodology is provided. Procedures are presented about paragraphs and sections of ANSI/ASHRAE/ASHE Standard 170-2017.


This report analyzes some sections and paragraphs of ANSI/ASHRAE/ASHE Standard 170-2017 in parallel existing hospital facility, practices, and the modality of treating a patient. The modalities will be referred to national medical associations and organization who are qualified to comment on best medical practices.  The level of analysis would focus on the operational, design and planning of medical facilities. Operational analysis would be able to make decisions on whether there is a need for minor, typical low-cost improvements that can be implemented immediately. Design analysis targets medium- and long-term project implementation that would allow a new or modified medical facility to operate at the desired level of infectious control performance in the transmission of air. Planning analyses are generally directed toward strategic issues; the time frame usually is long-term. The analysis can see the possibility of implementing medical facilities standard to other institutional facilities such as offices, malls, theatre, hotels and other institutional facilities where large number of people congregate. Planning studies might also assess and proposed safety policies of providing “safe haven” or area of refuge for health workers and doctors in a hospital.


The procedure did not account for any scientific laboratory research. It assumes ANSI/ASHRAE/ASHE Standard 170-2017 has confirmed computational procedures thru time and has been reviewed to be valid in facility operations.


  • Area of Refuge (Safe Haven) is define in NFPA 101 Life Safety Code section 3.3.23 as:

3.3.23* Area of Refuge. An area that is either (1) a story in a building where the building is protected throughout by an  approved, supervised automatic sprinkler system and has not less than two accessible rooms or spaces separated from each other by smoke-resisting partitions;  or (2) a space located in a path of travel leading to a public way that is protected from the effects of fire, either by means of separation from other spaces in the same building or by virtue of location, thereby permitting s delay in egress travel from any level. (SAF-MEA)

A.3.3.23 Area of Refuge. An area of refuge has a temporary use during egress. It generally serves as staging area that provides relative safety to its occupants while potential emergencies are assessed, decisions are made, and mitigating activities are begun. Taking refuge within such an area is thus, a stage of the total egress process, a stage between egress from the immediately threatened area and egress to a public way.

An area of refuge might be another building connected by the bridge or balcony, a compartment of a subdivided story, an elevator lobby, or an enlarged story-level exit stair landing. An area of refuge is accessible by means of horizontal travel or as a minimum, via an accessible route meeting the requirements of ICC/ANSI A 117. 1, Accessible and Usable Building and Facilities.

  • Airborne transmission is defined as the mode or means with which a microorganism is moved and transmitted via air and inhaled into the respiratory tract by the susceptible host. These infections are found in droplets and dust in the air. Airborne precautions are indicated in the presence of a pathogen that is transmitted via the airborne mode of transmission[1].

II. Methodology

The procedure for evaluating a section or paragraph involves first, the evaluation of the objectives of ANSI/ASHRAE/ASHE Standard 170-2017. Second, defining the nature of an “area of refuge [safe haven] for doctors and health personnel” Third, find existing sections and paragraphs that are related to or relevant to providing an area of refuge. Fourth, develop a section or paragraph that will make part of the standard. Fifth, submit the section or paragraph referring as an “area of refuge” for health workers in a hospital to medical professional organizations (MPO) and hospital owners (HO) for their comment and when necessary, for endorsement and recommendation. Sixth, Consolidate the comments of MPOs and HOs to formulate and consolidate the proposed section or paragraph. Finally, publish the section or paragraph statement to be commented by ASHRAE members.

III. Background History

Last April 3, 2020 I send this email to ASHRAE:

Dear Sir,


I am a member of ASHRAE and am in the Philippines.  The situation in the Philippines is not like the USA, however I am concerned with the situation in hospitals here where to this date 17 doctors have died due to Condiv-19. As an engineer in designing hospitals I would like to propose to develop an ASHRAE standard on “Safe haven for Medical Personnel in Hospitals” where the hospital corridors for patient rooms are designed as an Ante-Room to isolate the patient rooms from the rest of the hospital. I am designing a hospital now to conform to this concept. I am designing it for emergencies. I am designing it similar to an Infectious Disease Room except that all patient rooms are considered as an Infectious Disease area with the corridor as the anteroom.

Regards and Stay Safe,

Fernando S. Guevara PE ca, mn

Below is the email I received from ASHRAE thru Tanisha: 

“Hi Mr. Guevara,

We have received feedback from the Epidemic Task Force and the Chair of SSPC 170. The consensus is that this proposal can be served best within SSPC 170, Ventilation of Health Care Facilities. You can work with the Chair, Michael Sheerin (cc’d) to submit a continuous maintenance proposal. Instructions can be found here: https://www.ashrae.org/technical-resources/standards-and-guidelines/standards-and-guidelines-under-continuous-maintenance.

Below is the Chair’s feedback:

I think that the goals of this submission are better handled within the existing Standard 170 document rather than establish some alternate measure. There are a variety of ongoing lessons that we are all trying to assimilate and determine appropriate adjustments to the standard, and the concerns raised in this submission would become a part of that effort.  We feel for the experiences of the submitter and the intent to protect healthcare workers. It is important to find the right balance in changing HVAC / environmental controls and how much of an impact they would accomplish toward that goal, and integrate those factors into the holistic aspects and clinical practice actions that impact the overall safety and success of the healthcare staff.

I might also add that SSPC 170 can reach out to FGI and ASHE to develop white paper guidance that can more readily be shared as a better practice measure around this important subject.” 


[ Other Volunteers: Professor Fu-Jen Wang Professor of the National Chinyi University of Technology of Taiwan  fjwang@ncut.edu.tw , Professor Akio Miyara Professor of the  Department of Mechanical Engineering, Saga University, Japan miyara@me.saga-u.ac.jp,   Jaime Dungo Delegate / Member of the Philippines/DTI/BPS to the ISO/TC209 Technical Committee on Cleanrooms and Related Environment under the Vienna Agreement. Since 2011 to present. jaime@inquar.com ]

IV. Evaluation

1. The “Purpose” in ANSI/ASHRAE/ASHE Standard 170-2017 as shown below is the word “asepsis” as defined by the Registered Nurse.Org, refers to the scope of work by the health personnel and does not concern the ventilation system designed by hospital designers.

Asepsis is a medical protocol using medical techniques and sterilization methods to keep the absence of microorganism in a hospital environment. It did not mean preventing or removing airborne microorganism from entering a hospital environment.

Similarly, the word “asepsis” is mentioned in Paragraph 9 as shown below:

I propose to replace the word “asepsis” in the “Purpose” with the word “airborne transmission of microorganism” .

Also, replace the word “asepsis” in Paragraph 9 Space Ventilation with the word “airborne transmission of microorganism”.


Source: Registered Nurse Organization (USA)


2. Is it reasonable to add “and area of refuge [safe haven] for healthcare workers and medical doctors” in Section 2.1. of 2.0 Scope.

IV. Proposed Area of Refuge / Safe Haven for Medical Doctors and Health Personnel

XX. Ventilation- Area of Refuge or Safe Haven for Medical Personnel

An area that is either a story in a building where the building complies with NFPA 101 Life Safety Standard; located in a path of travel leading to a public way such as fire exit, or another building connected to the hospital by bridge or balcony.

“The ventilation requirements of this standard are minimum requirement that provide control environmental comfort, prevent airborne transmission of microorganism, and odor in a safe haven room; that complies with the minimum requirements assuring protection from discomfort, airborne transmission of contagions, and odors.”

Included Sections of ANSI/ASHRAE/ASHE:- 170-2017

Section 7.1 General Requirements

Section 9.1 General Requirements


  1. The room area for a safe haven or area of refuge should have a minimum of three exterior wall sides.
    1. One exterior wall side should have a balcony sufficient to accommodate ten persons at any given time.
    1. Corridor leading to the safe haven should be negative with respect to the room area.
    1. Prior to the entry into the safe haven room, ante room and shower facilities should be provided including a means of disposing PPEs.

[Fourth Step of the methodology will be submitted next time. Planning, Design and Planning analysis will be submitted after the Fourth step]

Submitted by:

Fernando S. Guevara

July 14, 2020

Fernando S. Guevara (fernando@gpiengineers.com), GPI Consulting Engineers, 98 V.A Rufino Street, Room 2312 Herrera Tower, Salcedo Village, Makati City, Philippines 1227

Email: fernando@gpiengineers.com

[1] Registered Nurse Organization

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