Health Facilities Designfor

Infection Control

Tobias van Reenen and Peta de Jager16 August 2013, Cape Town

“It may seem a strange principle to annunciate as the very first requirement in a hospital is that it do the sick no harm.”

Florence Nightingale

South African Constitution

Everyone is equal before the law and has the right to equal protection and benefit of the law.

Environmental rights in the Bill of Rights include the right to an environment that supports health and wellbeing. It also requires legislation to be developed to ensure that the environment is protected and that development that does occur is both sustainable, and justifiable:

Environment

Everyone has the right

a. to an environment that is not harmful to their health or well-being; and b. to have the environment protected, for the benefit of present and future generations, through reasonable legislative and other measures that

i. prevent pollution and ecological degradation; ii. promote conservation; and iii. secure ecologically sustainable development and use of natural resources while promoting justifiable economic and social development

IUSS Sustainability Guidelines Environmental objectives

• Environmental objectives• Energy: The building is energy efficient and uses

renewable energy• Water: The building minimises the consumption of mains

potable water.• Waste: The building minimizes emissions and waste

directed to landfill• Materials: Construction impacts of building are

minimized• Biodiversity: The building supports biodiversity

Mirebalais Hospital, Haiti – Nicholas Clark Architects Ltd.

Healthy, green health building: Economic objectives

• Economic objectives• Transport: The building supports energy efficient

transportation• Resource Use: The building makes efficient use of

resources• Management: The building is managed to support

sustainability• Local Economy: The building supports the local economy• Products and Services: The building supports use of more

sustainable products and service

Healthy, green health building: Social objectives

• Social objectives• Access• Health• Education• Inclusion• Social Cohesion

The “Florence Nightingale” Approach

• Florence Nightingale wrote over 150 years ago that open windows were the hallmark of a healthy hospital ward1

• Indoor microbial environments consist largely of human associated bacteria and pathogens.

• Outdoor microbial environments have a profile that look like plants and soil and are comparatively harmless

1 Nightigalen F. (1859). Notes on Nursing. D. Appleton: London.2Kembel, S. et al (2012)

• A 2012 study by University of Oregon proved that while clinics with open windows had more pathogens, closed window environments were more harmful2

• Ventilation method accounts

for a greater variance in airborne bacterial pathogenicity than ventilation rates alone2

2Kembel, S. W., Jones, … Green, J. L. (2012). Architectural design influences the diversity and structure of the built environment microbiome. The ISME Journal, 6(8), 1469–79.

Indoor air quality

Photo: Etienne du Plessis

South Africa’s oldest hospital:

Somerset Hospital. Circa 1890

• TB leading cause of mortality in South Africa4

• South Africa has the 3rd highest incidence of TB cases in the world3

• 5th highest number of drug-resistant TB cases in the world3

• 60% – 80% of all TB cases co-infected with HIV5,6

3 WHO. (2011). 4 Statistics South Africa. (2011). 5 WHO. (2009). 6 Gandhi et al. (2006).

Epidemiology

North Carolina State Sanatorium, men’s ward, 1926

• TB is spread by the airborne transmission route• Consider the occupational risks7,8

7 Joshi, R., Reingold A. L., Menzies, D., Pai, M. (2006). Tuberculosis among health-care workers in low- and middle-income countries: a systematic review. PlosMed 3(12);e494 (after Dr Paul Jensen)

8 Menzies, D., Joshi, R., Pai, M. (2006). Risk of tuberculosis infection and disease associated with work in healthcare settings. Int J Tuberc Lung Dis 11(6): 593-605 (after Dr Paul Jensen)

An issue of indoor air quality…

Work location Incidence(worker relative to general population)

Outpatient facilities 4.2 – 11.6

General medical wards 3.9 – 36.6

Inpatient facilities 14.6 – 99.0

Emergency rooms 26.6 – 31.9

Laboratories 42.5 – 135.3

Routes of infection

Adjacent Areas

Instruments

Room Air

FloorPersonnel

Mouth

Hands

Body

Adapted from Memarzadeh, 2003

Patient

Susceptible Infection Site

Building Services

Vectors

Sekgoma Memorial Hospital, Serowe

Sekgoma Memorial Hospital, Serowe

Occupants/equipment NOT ADAPTABLE or

tolerant of indoor

conditions

Occupants/equipment

ADAPTABLE or tolerant of

indoor conditions

Ventilation design philosophy

• Hierarchy of Design Solutions

Fully mechanical ventilation

Hybrid systems with climatic adaptability

Fully passive ventilation

Occu

pie

d a

rea

• Planning for passive ventilation, heating and cooling

• Layout and zoning for passive design responses

Specialist areas (ICU, surgery)

Intermediate areas (Trauma, food services)

General areas (Wards, waiting and public areas)

Ventilation design philosophy

• National Building Regulations and Building Standards Act (Act 103 of 1977)• SANS 10400 XA • SANS 10400 O• SANS 204

(Incorporated)

Standards and regulations

• Ventilation SANS10400-0• Table 2 all but

prohibits recirculation in health care buildings.

• Table 2 Excludes l/s/person calculations for health care buildings

Standards and regulations

WHY RECIRCULATE? • Consider a conditioned space which is maintained at

22C:• Cooling plant energy cost is reduced by between

80% and 95%: Advantage: • Lower energy and operating cost at the cooling

plant.• Smaller cooling plant and lower capital costDisadvantage: • More difficult to maintain indoor air quality

Source: Dr J Dirker UP

Standards and regulations

Adaptive approach-Increased air movement (-2°C)• Precise relationships between increased air speed

comfort have not been established.• Provide ability to control air speeds to < 0.8m/s• >0.2m/s can be considered draughty with HVAC

Thermal comfort

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Climatic classification (CSIR, 2010)

Climatic classificationDescription Köppen-

Geiger Class.Area in km²

Percentage (%)

Equatorial climates (0.2% of area)

Aw 2296.00 0.20

Arid climates (70.89% of area)

Bsh 192269.00 16.59

Bsk 275927.00 23.81

Bwh 188784.00 16.29

Bwk 164629.00 14.20

Warm temperate climates (28.91% of area)

Cfa 42918.00 3.70

Cfb 93405.00 8.06

Cfc 84.00 0.01

Csa 5120.00 0.44

Csb 18395.00 1.59

Cwa 31162.00 2.69

Cwb 140405.00 12.11

Cwc 3564.00 0.31

Total 1158958 100.00

Responsive design approaches

Bongani MDR TB Hospital, Mpumalanga T

HE

RM

AL

CO

MF

OR

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Design for climate

Skills of a multi-disciplinary team: but not business-as-usual

Surfaces and materials

• Smooth, hard, impervious surfaces create best hygienic environments

• Smooth, hard, impervious surfaces create the worst acoustic environments

http://designtoheal.org/case-studies/butaro-district-hospital/

Antimicrobial resistance

http://123sonography.com/blog/the-ignorant

Surfaces and materials

• Vinyl and tiled finishes create cavities behind which cannot be cleaned when bonding system fails

• Paint wall finishes recommended above vinyl

• Design/select fixtures which do not hinder cleaning

Surfaces and materials

• Consider materials’ environmental lifecycle• Origin• Durability• Toxicity• Recycling• Disposal

• Consider vinyl if:• BRE A+ Rating = 100%

recyclable• Pass VOC emissions test• Consider toxicity of

adhesives

http://designtoheal.org/case-studies/butaro-district-hospital/

Planning

IUSS Central Sterile Service Department

Engineering Services

Healthy, green health building: A 3–pronged approach

• Consumption and emissions• Benchmarks, targets,

minima• Monitoring and progressive

improvement• Rework professional duties,

interdisciplinary relationships and incentives

• Life cycle analysis• Components and materials• Whole building• Appreciate sector-specific

challenges

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2023-04-11

QUESTIONS?

Resources & References

Bibby, C., & Hodgson, M. (2013). Prediction study of factors affecting speech privacy between rooms and the effect of ventilation openings. Applied Acoustics, 74(4), 585–590.

ASHRAE 55-2004; Thermal environmental conditions for human occupant, 2004.

ISO 7730:2005 Ergonomics of the thermal environment -- Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria

CIBSE AM10; Irving, S., Ford, B., & Etheridge, D. (David W. . (2005). Natural ventilation in non-domestic buildings.

CIBSE. (2000). CIBSE Applications Manual AM13: Mixed mode ventilation.

CCIBSE. CIBSE Knowledge Series KS17— Indoor air quality and ventilation.

Nightingale, F. (1859). Notes on Nursing. D. Appleton: London.Kembel, S. W., Jones, … Green, J. L. (2012). Architectural design influences the diversity and structure of the built environment microbiome. The ISME journal, 6(8), 1469–79

Resources & References

• CDC• CSIR• FIDSSA –Federation of Infectious Diseases of South Africa• ICAN –Infection Control African Network• MRC - Medical Research Council• National Department of Health – www.iussonline.co.za • NHLS – National Health Laboratory Services

• NIOH – National Institute of Occupational Health• NICD – National Institute of Communicable Diseases

• SAFHE – South African Federation of Hospital Engineering• WHO