Interim Recommendations for Cleanup of Commercial and Residential Buildings Following Bacillus anthracis Spore Release 

1.	Introduction 	

This document provides interim recommendations for clean up after a release of Bacillus anthracis (B.anthracis). The U.S. Environmental Protection Agency (EPA) has primary authority in matters concerning environmental hazards and cleanup. EPA reviewed and commented on this guidance document. 
				
The issues involved in cleanup of a workplace, residence or other type of structure contaminated by B. anthracis spores vary significantly from place to place.  These differences preclude the development of universal recommendations. Decisions regarding a strategy for cleanup must be based on each situation.  Consult with the EPA, state or local health departments, the manufacturers of building contents, building owners or managers and others, as needed. This document provides information and guidance regarding issues that must be considered for cleanup of a contaminated building.  The key issues covered here include: the conduct of a site assessment, development of a cleanup plan, selection of cleaning materials and disinfectants, selection of personal protective equipment, and disposal of contaminated solid waste and liquids. 

2.	Site Assessment and Cleanup Plan 
2.1	Site Assessment						
The site assessment includes an evaluation of the extent of the problem and confirmation of the presence of B. anthracis. Protection of personnel performing the assessment is a primary concern (http://www.cdc.gov/niosh/unp-anthrax-ppe.html). The site assessment includes a qualitative overview: 

$	How the B. anthracis was brought into the facility or dwelling (e.g., through a mail package, air handler, or other mechanism). 
$	Possible pathways by which B. anthracis could have spread. 
$	The type of environmental surfaces (e.g., ceiling tiles, walls, counters, floor covers, air ducts, furnishings, etc.) involved.
$	The location and extent of contamination, evidence for spread of contamination, and potential for re-distribution.
$	The need for and appropriateness of occupying uncontaminated areas during cleanup. 

Part of the site assessment includes the collection of environmental samples to confirm the presence of B. anthracis. Strategy and methods for conducting environmental sample collection are specified in the following CDC publications: Guidelines for Developing an Environmental Sampling Strategy for Bacillus anthracis in Mail-Processing Facilities and Procedures for Collecting Surface Environmental Samples for Culturing Bacillus anthracis (http://www.bt.cdc.gov/DocumentsApp/Anthrax/11132001/final42.asp). Procedures to package samples for transport to testing laboratories are specified in CDC publication: Packaging Critical Biologic Agents (http://www.bt.cdc.gov/LabIssues/PackagingInfo.pdf).

If B. anthracis contamination is confirmed and occupancy necessary, a professional remediator, in consultation with local public health and law enforcement authorities and building managers or owners, should develop a comprehensive remediation plan that meets environmental and occupational health objectives.  The site remediation plan must include safety and infection control procedures that protect cleanup workers inside and outside the area, and includes site and task-specific work plans for post-remediation sampling, contaminated area isolation, recovery of critical items, remediation and verification sampling. These interim recommendations describe administrative, engineering, housekeeping controls, and personal protective equipment (PPE) issues essential to building cleanup procedures that should be addressed within a site remediation plan.

2.2	Cleanup Procedures  

2.2.1	General guidance 

Overall approaches to cleanup vary depending on whether contamination is localized or occurs throughout the building. There is no single procedure or guideline for disinfection of spaces and materials contaminated with B. anthracis. Judgment based on a thorough understanding of the extent of the original contamination is used to define the degree of cleaning required. It is likely that a single cleaning approach will not be suitable for all local and building-wide B. anthracis contamination scenarios.  

The selection of cleanup option(s) should be based and prioritized on:
•	Biocidal performance on non-porous and porous vertical and horizontal surfaces 
•	Compatibility with the contaminated material to minimize the creation of additional hazardous conditions
•	Ability to minimize generation of hazardous waste
•	Minimization of post-cleanup adverse health effects 
•	Effectiveness of cleanup options 

All cleanup strategies should be developed by a team of qualified experts with experience in biological and or infectious disease control with input from the building owner/operator, architect, employees and other knowledgeable persons most familiar with the design, layout, and operation of the building structure and processes. The strategy for cleanup should be reviewed and approved by local public health and safety authorities.    

2.2.2		Administrative Controls

Worker safety and health during the cleanup of a site contaminated with B. anthracis is covered under a number of regulations that should be followed by the employer. A key standard is 29 CFR. Hazardous Waste Operations and Emergency Response (HAZWOPER –1910.0120 http://www.osha-lc.gov/OshStd_data/1910_0120.html). Employer responsibilities include, but are not limited to, the following key items:
•	Develop a comprehensive site-specific health and safety plan in consultation with local public safety and health authorities prior to implementing any remediation activities.
•	Develop a medical surveillance program
•	Develop a personal protective equipment program
•	Ensure that all remediation workers who will be wearing respirators have a current respirator fit test (29 CFR. Respiratory Protection. - 1910.134  http://www.osha-slc.gov/OshStd_data/1910_0134.html ).
•	Ensure that remediation workers have received appropriate safety and infection control training and in-service education. All designated decontamination team members should have the following minimum training experience:
•	40 hour hazardous waste operations training.
•	Basic hazard communication training concerning B. anthracis and the specific decontamination chemicals to be used on the site.
•	Develop strategies for security and emergency response in consultation with local public safety and public health officials prior to beginning cleanup activities.

Other recommended administrative controls:
•	Develop strategies to restrict the number of persons entering, working or adjacent to contaminated sites to limit exposure to aerosolized particles generated during cleanup and disposal operations.

•	Due to the possibility of breaches of personal protective equipment and exposure of workers, CDC recommends that decontamination/cleanup workers receive antimicrobial prophylaxis.  Prophylaxis will entail the use of standard regimens starting in conjunction with or prior to the time of first entry into a contaminated site and continuing for 60 days after final opportunity for exposure. The current recommended regimens (for adults) are as follows:
Ciprofloxacin, 500 mg by mouth every 12 hours, or 
Doxycycline, 100 mg by mouth every 12 hours
A medical protocol should be developed to implement prophylaxis, and the program should be under the supervision of an experienced physician. These recommendations may be modified as additional information becomes available (Centers for Disease Control and Prevention. (2001) Antimicrobial Prophylaxis to Prevent Anthrax Among Decontamination/CleanupWorkers Responding to an Intentional Distribution of B. anthracis).

•	For workers who may have prolonged or repeated employment on sites potentially contaminated with B. anthracis, CDC recommends routine vaccination with anthrax vaccine adsorbed (AVA). Consultation with an experienced physician should be made before receiving the vaccine.  Immunization consists of three subcutaneous injections given 2 weeks apart, followed by three additional subcutaneous injections at 6,12, and 18 months.
o	(Centers for Disease Control and Prevention: FAQ’s about Anthrax: http://www.bt.cdc.gov/DocumentsApp/faqanthrax.asp - topic9; 
o	Centers for Disease Control and Prevention (2000) http://www.cdc.gov/mmwr/preview/mmwrhtml/rr4915a1.htm)

2.2.3	Engineering Controls
Develop strategies to minimize the aerosolization of B. anthracis to reduce the risk of inhalation anthrax, the most severe form of the disease. Engineering controls must be in place to prevent operating machinery and air-conditioning (HVAC) systems from spreading spores, and to prevent the redistribution of spores by personnel and equipment, removal of PPE, as well as waste collection, storage, transport and disposal activities.

2.3.4   Personal Protective Equipment     
Personnel entering the area to conduct sampling or cleanup activities will wear the level and type of personal protective equipment (PPE) appropriate to the expected hazard. Protective clothing (including chemical protective coveralls, shoe covers, and gloves) prevents skin exposure to spores or to disinfectant, and prevents contamination of street clothes. Eye protection must be used to prevent splash exposure to disinfectants (a full‑facepiece respirator provides splash protection). Respiratory protection must be selected in accordance with the level of respiratory exposure hazard (biological & chemical). The Permissible Exposure Limit (PEL), Recommended Exposure Limit (REL) and the Immediately Dangerous to Life and Health values for selected fumigants are noted in Appendix A. Refer to the following standards and recommendations for additional guidance:
•	29 CFR. Hazardous Waste Operations and Emergency Response (HAZWOPER) –1910.0120 http://www.osha-slc.gov/OshStd_data/1910_0120.html)
•	29 CFR. General Requirements - Personal Protective Equipment http://www.osha-slc.gov/OshStd_data/1910_0132.html;
•	29 CFR. Respiratory Protection. - 1910.134 http://www.osha-slc.gov/OshStd_data/1910_0134.html; 
•	29 CFR.  Hand Protection. - 1910.138 http://www.osha-slc.gov/OshStd_data/1910_0138.html;  
•	Protecting Investigators Performing Environmental Sampling for Bacillus anthracis: Personal Protective Equipment. http://www.cdc.gov/niosh/unp-anthrax-ppe.html).
•	Eye Safety: Emergency Response & Disaster Recovery http://www.cdc.gov/niosh/eyesafe.html
•	Interim Recommendations for the Selection and Use of Protective Clothing and Respirators Against Biological Agents http://www.bt.cdc.gov/DocumentsApp/Anthrax/Protective/Protective.asp	

As personnel leave the contaminated area, they must remove their protective clothing in a manner that will not spread B. anthracis spores that may be on their protective clothing and equipment. PPE can be cleaned with a 1:9 household bleach and water. For disposal of dirty cleaning solutions, cleaning supplies and PPE see Section 4:Disposal of Waste Materials/Wastewater.  

2.3.5	Housekeeping Controls

The following housekeeping controls should be considered for effective cleanup:
•	Develop a cleanup strategy, or combination of cleanup strategies to address the surface type to be cleaned (e.g. hard surface, porous material, or fabric). 
•	Select disinfectants based upon the proven effectiveness against the spore form of the B. anthracis. The microbial and sporicidal effectiveness of disinfectants are dependent upon the use of the appropriate concentration, contact time, temperature, and pH range. 
•	Select cleanup strategies on the effectiveness of the disinfectant(s) to kill or inactivate B. anthracis spores on various surfaces (see above). Consideration of secondary effects, such as chemical/thermolytic reactions, staining and fading, out-gassing and odor, corrosion of metals, and electronics compatibility, should receive lower priority than the effectiveness of the disinfectant(s).
•	Clean with gentle motions. Do not clean surfaces using compressed air or methods that can generate dust and re-aerosolize spores.       
•	Clean contaminated areas with wet techniques. Avoid dry sweeping and dusting. 
•	Dispose of nonessential materials prior to cleanup to improve effectiveness of building cleanup.  See Section 4. 
•	Handle all contaminated waste materials consistent with local medical waste regulations.  See Section 4. 
•	Wash hands thoroughly with soap and water as soon as possible after removing PPE, and before eating.
•	Analyze and interpret results of post-cleanup environmental sampling to evaluate the effectiveness of the cleanup procedure. Local authorities using the pre-cleaning criteria should conduct this step.

2.2.6 	Specific Housekeeping Procedures

2.2.6.1		Separating "clean" and "dirty" areas  

Depending upon the size of the contaminated area, the types of surfaces, and the extent of contamination, it may be necessary to isolate or seal-off the contaminated area to prevent the spread of spores by the movement of people or equipment. Based on the recent results demonstrating the ability of B. anthracis spores to be re-aerosolized during normal office activities, cordoning off a contaminated area is not recommended.
	To isolate or seal-off the contaminated area the following is recommended:
•	Use impervious plastic (e.g., 6 mil - polypropylene) sheeting to devise temporary barriers. 
•	Maintain, using tape, tight seals at the full perimeter of temporary walls and at ceiling height in the same way that areas are sealed off for asbestos abatement and dust control during building renovation (29 CFR.  Asbestos -  1926.1101, Section G, Part 4.  http://www.osha-slc.gov/OshStd_data/1926_1101.html for temporary barrier construction guidance). 
•	Seal windows and air vents serving the area using plastic sheeting and tape to control the risk of dust dispersal and recirculation
•	Keep the area under negative air pressure to prevent the outward flow of air to produce a higher level of isolation. Portable high-efficiency particulate air (HEPA)-filtered negative air units can be used to produce negative pressure environment. This equipment may be leased or purchased.

2.2.6.2	Pre‑cleaning  

Standard institutional cleaning practices recommend that surfaces be cleaned prior to disinfection. Any dirt or other material on the surface to be cleaned will decrease the efficacy of disinfectant solutions. 

Use the following procedures to pre‑clean most surfaces:
•	Wet wipe surfaces with a cleaning solution of detergent and water to remove existing organic load.
•	Focus on walls and horizontal surfaces. Avoid aggressive pre-cleaning (use gentle actions) to prevent the re-aerosolization of dust that may contain spores.  

For a grossly contaminated area (visible powder) use the following procedures:
•	Gently flood the contaminated area with a solution of 1 part household bleach in 9 parts water
•	Let the solution stand for 30 minutes minimum
•	Clean with the detergent and water solution.

For disposal of dirty cleaning solutions, cleaning supplies and PPE see Section 4:  Disposal of Waste Materials/Wastewater.  

2.2.6.3	 HEPA-filtered Vacuuming Equipment for Surface Cleaning 

If vacuum equipment is used in remediation, select heavy-duty industrial type 

vacuums manufactured for hazardous dust abatement activities, with sufficient 
vacuum strength and durability, and equipped and maintained with effective high efficiency particulate (HEPA) filters. HEPA vacuuming has been proposed for dust reduction for fabric-covered furniture, carpets, electronic equipment, artifacts and other fixed surfaces; however, the efficacy of this method is not proven in B. anthracis remediation activities or laboratory settings. Central, one pass, HEPA vacuum system might be preferable to portable vacuum units since exhaust air will not blow more dust into the air or re-distribute dust into previously cleaned areas. Engineering controls, such as isolation tents, must be in place to minimize the generation of dust when changing pre-filters and HEPA filter materials contained in the vacuums.
Note: HEPA vacuuming alone, whether done once or repeated several times, may not be sufficient to clean up porous, portable or fixed surfaces. See Section 3: Disinfection Methods. Vacuuming of carpet may prove to be particularly problematic and both time and labor intensive. Filter materials should be collected, stored, and disposed in compliance with applicable hazardous solid waste regulations see Section 4.

  3.   Disinfection Methods

Several methods exist for cleanup. The following options can be considered by public health authorities to determine the cleanup method necessary for a safe and acceptable environment. 

3.1 	Simple Cleaning
The steps described for pre-cleaning may remove much of the B. anthracis load from the contaminated surfaces, but is unlikely to result in adequate surface cleaning. 

3.2	Sodium hypochlorite solution
To make a solution of sodium hypochlorite mix 1 part household bleach to 9 parts water. This solution will be used to flood non‑porous surfaces. Using the bleach solution further reduces viable spore load. Porous surfaces, such as carpets, fabric drapes, acoustical ceiling tile and wallpaper, can be treated with the bleach solution but must be removed and properly discarded after treatment. See details in Appendix B.

Note: Exposure to sodium hypochlorite solution may cause a number of health effects:
•	Inhalation: Irritation to the respiratory tract (nose and throat); symptoms may include coughing and sore throat
•	Ingestion: Nausea, vomiting
•	Skin contact: Skin irritation
•	Eye contact: Severe irritation and damage, particularly at high concentration
•	Aggravation of pre-existing conditions: Persons with chronic respiratory disease such as asthma, chronic bronchitis/obstructive lung disease, or heart disease may be more susceptible.

Note: Some common institutional cleaning agents should never be used together with bleach solutions. For example, bleach forms toxic gases when mixed with certain products such as ammonia.

3.3	Disinfecting with Gaseous Formaldehyde using Paraformaldehyde crystals
Gaseous formaldehyde is used to disinfect large contaminated spaces (such as rooms or buildings). See Appendix C for detailed procedures. 
Note: Formaldehyde is a potential carcinogen, so this method should be used only if no other option is practical or realistic. OSHA standards for Formaldehyde should be followed (CFR 29 – 1910.1048 http://www.osha-slc.gov/OshStd_data/1910_1048.html ).

3.4 	Other Options for Disinfecting Building Areas
Consideration should be given to innovative technologies when current technologies and strategies have shown limited success, could create significant 
financial hardships or unacceptable disruptions of vital services. The selection and use of these alternative agents and methods should be undertaken in consultation with appropriate public health authorities. 

Other potentially feasible disinfecting methods and techniques are currently under investigation. The use of ozone, ionizing and non-ionizing radiation, ultraviolent light, gas fumigants, and other than formaldehyde and other alternative disinfecting agents not addressed in this document are not currently recommended by the CDC due to unknown or unproven microbial and or sporicidal effectiveness, and the feasibility of these agents or application methods on environmental surfaces in buildings. This determination may change in the future as additional information becomes available.

4.0	 Disposal of Contaminated Solid and Liquid Wastes
All B. anthracis-contaminated solid waste and liquids must be handled in a manner no less stringent than specified medical waste regulations. Biological wastes, including B. anthracis-contaminated materials, are governed under Resource Conservation and Recovery Act (RCRA) http://www.epa.gov/rcraonline/); and, State, Territory and Tribal environmental agencies are also authorized to control the location and method of disposal of B. anthracis-contaminated materials. For information on disposal of medical waste by state, contact the RCRA, Superfund & EPCRA Call Center at 1-800-424-9346. In addition, the release of B. anthracis into the environment as a result of a bio-terrorist event triggers reportable quantity notifications established under CERCLA and, therefore, must be reported to the National Response Center (1-800-424-8802). 

	5.0	Special considerations
		5.1	Special Needs for Equipment

Some objects with internal cooling ventilation fans (e.g., desktop computers) draw cooling air into the case and may include filters or electrostatic methods to control dust intake. These filters or the equipment chassis may be reservoirs of contamination. If contamination is a concern, store the equipment in a sealed plastic bag prior to environmental cleanup, and consult the equipment's manufacturer for disinfectant compatibility issues. 

		5.2	Heating, Ventilation, and Air Conditioning Systems

Some B. anthracis incidents, particularly those involving spores that are particularly likely to become airborne, may contaminate air ducts and other parts of heating, ventilation, and HVAC systems, including filters. Filters for HVAC systems serving contaminated areas should be removed and replaced. The filters should be bagged and labeled appropriately for incineration. Personnel performing these operations should wear personal protective equipment specified for cleanup.

The HVAC ducts, particularly exhaust ducts, serving the contaminated area should be sampled for contamination. HVAC dampers should be sampled if an outside source is suspected. At a minimum, vacuum samples should be collected from HVAC system filters, and wipe samples should be collected from room supply registers and return grills. If HVAC ducts are contaminated, they must be cleaned and disinfected.  If mechanical cleaning and disinfection are not possible, gaseous disinfection may be needed. Cleanup of fiberglass-lined duct work with biocides is of concern due to the fact that spores may have been deposited in the organic material built up in the duct work.  Organic material interferes with the biocidal activity of fumigants, disinfectants and chemical germicides. In addition, spores may become trapped in the insulating materials, and depending upon the penetration of the fumigant, may or may not be fully killed or inactivated.

		5.3   Shoes, Apparel and Linen

Contaminated shoes, apparel and linen may be discarded in compliance with local and State regulations for the disposal of pathological waste, or they may be retained for disinfection. Do NOT launder contaminated clothing at home. If kept for re-use, contaminated clothing should be placed into autoclave bags for autoclaving or disinfecting following infection control guidelines for the collection, transport, and treatment of biohazard materials.

Dry cleaning cannot be relied on to disinfect clothing contaminated with B. anthracis.  Although little is known about the effectiveness of dry cleaning in destroying bacteria and other microorganisms, it has been found to be ineffective against some viruses, which are often less hardy than spores. Draft: Project #138 – FAQs on Handling and Cleanup (Anthrax)

		5.4 Rodent and Insect Vector Control

Cross contamination by crawling and flying insects and rodents may be possible. A vector control program should be implemented to the extent feasible based on a site-specific vector control assessment. Control programs should be developed in consultation with local licensed pest control authorities and implemented, if possible, prior to any structural fumigation. Any rodents eradicated through this control program should be collected for disposal, sealed in labeled plastic bag, and incinerated. Personnel handling dead rodents should wear appropriate PPE and follow standard infection control precautions.

	5.5	Pets and Other Animals
Pets and other animals may be exposed to B. anthracis and should be quarantined on-site as promptly as possible.  It may be feasible to perform animal cleaning for some species.   Animals dying after exposure should not be handled and should be reported to public health authorities.  Issues related to disinfection, vaccination, prophylaxis, duration of quarantine, or the decision to euthanize, animals are beyond the scope of this guideline and should be initiated only in consultation with a knowledgeable veterinarian, and in compliance with local, State and international public health regulations or guidelines such as those contained in WHO Guidelines for the Surveillance and Control of Anthrax in Human and Animals, 3rd edition (http://www.who.int/emc-documents/zoonoses/whoemczdi986c.html).

		5.6 	Chemical Sensitive Artifacts, Artwork and Antiquities 
If damage to artifacts, artwork and antiques from cleanup is a concern, store the artifacts in an appropriate and secure location in sealed plastic bags (double bag, if possible) or other appropriate protective container, and label with biohazard warning labels prior to environmental cleanup. Consult appropriate equipment manufacturer, art restoration, or other experts for guidance on effect of cleaning and disinfection measures on the integrity of these items.

6.0	Public Notifications, Property Transfer and Other Record Keeping
Related to cleanup and waste disposal activities, the property owner or manager may be subject to public notification and health and safety placarding regulations, and hazardous waste manifesting, occupational health/OSHA, or veterinary record keeping requirements. Other local property recording and recordkeeping requirements related to property transfer may be instituted by various other local authorities. Owners or managers should consult legal counsel to determine their responsibilities and to fully understand compliance requirements. 

	7.0.   Post‑Cleaning Testing, Verification and Notification Prior to Re-entry
   
Wipe samples or vacuum samples will be collected in a representative sample of cleaned areas (see separate guidance document for sampling). Each of these areas should be sampled using the same method by which it was sampled before cleaning. Local authorities should interpret the results of post-cleaning environmental sampling.  If any of these post‑cleaning samples show residual contamination, those areas should be cleaned again  Prior to recleaning, areas without contamination should be isolated from the areas with residual contamination as described in Section 2.2.6.1, cleaned and resampled.   

The owner or manager of the building is responsible for notification of local unions, management associations, and employees as soon as possible of the results of post-decontamination sampling.

Decontamination verification is required prior to re-entry and occupation of the premises. Based on current information, the safety of the public or workers cannot be assured if B. anthracis-contamination is present in the building.

 8.0	Interim Custodial Cleaning Procedures for Non-Contaminated Areas Adjacent to Contaminated Spaces

These guidelines are for routine cleaning and disposition of trash in areas and facilities adjacent to but not identified as contaminated with B. anthracis.  The cleaning of areas adjacent to contaminated spaces should be specified in the written site-specific safety and infection control plan previously described.

8.1 Custodial Procedures
•	Optional protective equipment  - Custodians and waste handlers may choose to wear a properly fitted, NIOSH-approved filtering face piece respirator (N-95) and nitrile or vinyl gloves for comfort.  PPE should be inspected frequently, and worn out or damaged gloves and respirators can be placed in the trash.  

•	Reducing dust - Use wet methods or a vacuum cleaner equipped with a high efficiency particulate (HEPA) filter.  For wet mopping or wiping, a 10% bleach solution (1-1/2 cups of household chlorine bleach in 1 gallon of water or 1 part bleach to 9 parts water) can be used. Avoid dry mopping or sweeping.

•	Changing vacuum bags - Keep dust to a minimum when changing vacuum bags.  Put the full vacuum bag gently in a plastic bag.  Seal the plastic bag and put it in the trash.

•	Trash removal - Put trash into a plastic bag and seal the bag. Incinerate or bury trash in a sanitary landfill. Concern about B. anthracis contamination in locations not experiencing a hazardous materials incident does not justify identifying the trash as biohazardous waste unless the waste actually does contain pathological waste as defined in OSHA Bloodborne Pathogens Standard (29 CFR Part 1910.1030 http://www.osha-slc.gov/Preamble/Blood_toc/Blood_toc_by_sect.html). 
 
•	Integration of existing safety and disaster plans - Pre-contamination emergency preparedness and security plans and procedures should be reviewed and revised if needed. In any location experiencing a hazardous materials incident, HAZMAT procedures should be followed.

•	Personal hygiene habits for custodians and trash handlers
•	Cover any open wounds, cuts, scratches, rashes.  
•	Don’t eat, drink, smoke, or chew gum while working.   
•	Never reach where you can’t see.  If you are cut or stabbed by a sharp object while handling trash, immediately wash the area with soap and water, and report it as soon as possible to your supervisor. Seek medical treatment.
•	Wash hands after custodial and trash handling work, and before eating.

REFERENCES

Bartley JM.  APIC State-of-the-art report:  The role of infection control during construction in health care facilities.  Am J  Infect Control  2000; 28:156-169.

Centers for Disease Control.  Field Investigation - Evaluation of Decontamination of Textile Mill for Bacillus anthracis.  EPI-72-94-I, Centers for Disease Control, DHEW, Atlanta, GA.  June 1, 1972.

Centers for Disease Control.  Biosafety in Biomedical and Microbiological Laboratories, 4th Edition.  U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention and National Institutes of Health, U.S. Government Printing Office Washington: 1999. (See http://www.cdc.gov/od/ohs/pdffiles/4th%20BMBL.pdf)

Centers for Disease Control.  Packaging Critical Biological Agents. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention and National Institutes of Health, U.S. Government Printing Office Washington: 2000. (See http://www.bt.cdc.gov/LabIssues/PackagingInfo.pdf)

Centers for Disease Control and Prevention. Use of Anthrax Vaccine in the United States: Recommendations of the Advisory Committee on Immunization Practices (ACIP) U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, Atlanta, GA 30333: 2000.

Cheney JL.  Formaldehyde fumigation of laboratory rooms. J Med Lab Technol  1992; 49(3):199.

Code of Federal Regulation.  Asbestos - 1926.1101, Section G, Part 4.  (See http://www.osha-slc.gov/OshStd_data/1926_1101.html  for temporary barrier construction guidance).

Favero MS, Bond WW. Sterilization, disinfection, and antisepsis in the hospital, pp 183-200.  In Manual of Clinical Microbiology, 5th edition, edited by A. Barlows, et al. Washington, D.C., American Society for Microbiology 1991

Hawley RJ, Eitzen Jr, EM.  Biological weapons—a primer for microbiologists.  Annu Rev. Microbiol 2001; 55:235–253. 

Lach VH.  A study of conventional formaldehyde fumigation methods.  J Appl Bacteriol 1990; 68(5):471-478

Ivans BE, Fellows P, Pitt ML et al. Efficacy of standard human anthrax vaccine against Bacillus anthracis aerosol spore challenge in rhesus monkeys. Salisbury Med Bull 1996;87:126-126.

Monro K, Lanser J, Flower, R.   A comparative study of methods to validate formaldehyde decontamination of biological safety.  Appl Environ Microbiol 1999; 65;873–876

National Sanitation Foundation International, Class II (Laminar Flow) Biohazard Cabinetry, Standard 49, 1992, Annex G: Recommended Microbiological Decontamination Procedure.

Rutala WA.  APIC guidelines for selection and use of disinfectants.  American J Infection Control.1996; 24:313-342.

Rutala WA, Weber DJ.  Use of inorganic hypochlorite (bleach) in healthcare facilities.  Clin Microbiol Rev 1997; 10:597-610

World Health Organization.  Guidelines for the Surveillance and Control of Anthrax in
Human and Animals. 3 rd edition.  World Health Organization, Geneva, Switzerland, June 1998.  (Found at http://www.who.int/emc-documents/zoonoses/whoemczdi986c.html).

Appendix A. Permissible and Recommended Exposure Limits and IDLH1 values for Selected Chemical Fumigants
Disinfectant Agent	NIOSH Recommended Exposure Limit (REL)	Immediately Dangerous to Life and Health (IDLH)1	OSHA Permissible Level (PEL)	
Chlorine Dioxide	0.1 ppm TWA2	5 ppm	0.1 ppm TWA	
Ethylene Oxide	<0.1 ppm TWA	800 ppm	1 ppm TWA	
Formaldehyde	0.016 ppm TWA
 0.1 ppm 15 min	20 ppm	0.75 ppm TWA	
Glutaraldehyde	0.2 ppm Ceiling	None established	0.2 ppm Ceiling	
Hydrogen peroxide	1.00 ppm TWA	1.00 ppm	75 ppm TWA	
Peracetic acid	None established	None established	None established	
ß-propiolactone§¥	Carcinogen	Carcinogen	Carcinogen	
Propylene Oxide	None established	400 ppm	100 ppm TWA	
Ozone	0.1 ppm  Ceiling	5 ppm	0.1 ppm TWA	

1Immediately Dangerous to Life and Health (IDLH) - The current NIOSH definition for an immediately dangerous to life or health condition, as given in the NIOSH Respirator Decision Logic [NIOSH 1987], is a situation "that poses a threat of exposure to airborne contaminants when that exposure is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from such an environment." It is also stated that the purpose of establishing an IDLH is to "ensure that the worker can escape from a given contaminated environment in the event of failure of the respiratory protection equipment. 

2TWA- Time weighted average usually over a 10 hr period.
§ Designated as a carcinogen.
¥ TLV 0.5 ppm; 1.5 mg/m3

 
Appendix B.  Cleanup Procedures 
Using Sodium Hypochlorite Solution

1. Cleanup of non‑porous surfaces (e.g., work surfaces, computer equipment, file cabinets, vinyl floors, painted walls, and ceilings) 
     
1.1		General Precautions

•	Stage materials and equipment as necessary to begin the cleaning effort. 

•	Begin work only after a personnel decontamination station is installed and personnel are trained.

•	Ensure personnel appropriately select, don, use, doff, and maintain their PPE as outlined in the site-specific safety and infection control plan.

•	Ensure that medical management plans, including any required prophylaxis and medical monitoring are in place and being implemented.

•	Bleach forms toxic gases when mixed with acidic substances such as ammonia, toilet bowl cleaners, drain cleaner, or vinegar.  Do not mix bleach with other cleaners.

•	Turn off electrical devices prior to cleaning. Liquid cleaners and disinfectants should not used on electrical appliances while they are plugged into an electrical source.

	1.2		Cleanup methods

•	Preclean all surfaces of concern
•	Prepare cleaning solution using liquid household bleach (5.25% to 6.15% solution.)
o	 Add 1 part bleach to 9 parts water, resulting in a solution containing 5,250 to 6,150 parts per million (ppm) free available chlorine. The final solution should have a pH range between 6 and 8.
o	 Prepare solution immediately before use 
o	 Do not store solution because storage reduces the free available chlorine and the disinfectant ability.
•	Apply the solution to the contaminated surface. If using a spray applicator, set the spray applicator on Amist@ or at a 45 degree or higher spread and spray 6 to 8 inches away from the surface. This prevents reaerosolizing the spores.
•	Leave the solution on the surface for a minimum of 10 minutes (contact time).
•	Rinse (wipe) the cleaned areas with a solution of water and sodium thiosulphate (20 grams thiosulphate to 1‑gallon of water) to neutralize the bleach. This will help protect the surfaces and prevent chlorine from interfering with cultures of samples collected after cleaning.     
•	Rinse (wipe) surfaces with clean water to remove any residue.

1.3		Post-Cleanup methods 
o	Dispose of materials used in the cleanup (bleach, moistened cloths, sponges) as other normal household wastes.  
o	Remove PPE in reverse order of donning, removing the outer pair of surgical gloves, chemical protective coveralls, shoe covers, and respirator. The last item to be removed is the second pair of surgical gloves. Used clothing should be bagged and labeled for disposal. See Section 4: Solid Waste Disposal.
o	Wash hands immediately with soap and warm water for at least 30 seconds after removing PPE.      

2.	Disposal of items with porous surfaces (e.g., carpeting, cloth‑covered furniture)    

	2.1	General Precautions

•	Stage materials and equipment as necessary to begin the cleaning effort. 

•	Begin work only after a personnel decontamination station is installed and personnel are trained.

•	Ensure personnel appropriately select, don, use, doff, and maintain their PPE as outlined in the site-specific safety and infection control plan.

•	Ensure that medical management plans, including any required prophylaxis and medical monitoring are in place and being implemented.

•	Bleach forms toxic gases when mixed with acidic substances such as ammonia, toilet bowl cleaners, drain cleaner, or vinegar.  Do not mix bleach with other cleaners.

•	Turn off electrical devices prior to cleaning. Liquid cleaners and disinfectants should not used on electrical appliances while they are plugged into an electrical source.

	2.2 Cleanup Methods
•	Treat in place contaminated carpeted and cloth‑covered areas or materials by applying the bleach solution until the surface is moist. 
•	Remove and dispose of treated material(s) as solid waste.
      
	2.3		Post-Cleanup methods 
o	Dispose of materials used in the cleanup (bleach, moistened cloths, sponges) as other normal household wastes.  
o	Remove PPE in reverse order of donning, removing the outer pair of surgical gloves, chemical protective coveralls, shoe covers, and respirator. The last item to be removed is the second pair of surgical gloves. Used clothing should be bagged and labeled for disposal. See Section 4:Solid Waste Disposal.
o	Wash hands immediately with soap and warm water for at least 30 seconds after removing PPE.
o	Vacuum carpets outside the contaminated area with an appropriate HEPA-filtered vacuum or shampoo carpet.

Appendix C. 
Cleanup Procedures Using Gaseous Formaldehyde

Commercial devices are available that automate the gaseous formaldehyde cleanup is abstracted from U.S. Army Medical Research Institute for Infectious Diseases Regulation 385‑17 and from Class II (Laminar Flow) Biohazard Cabinetry, National Sanitation Foundation International, Standard 49, 1992, Annex G.
Note: Formaldehyde should be handled with caution. Porous materials may out-gas formaldehyde for extended periods. Formaldehyde is a potential carcinogen, so this method should be used only if no other option is practical or feasible. Follow OSHA Regulations as specified CFR 29 1910.1048. http://www.osha-slc.gov/OshStd_data/1910_1048.html

1.	Pre cleanup Methods
o	Pre-clean the area to remove dust and dirt with disinfectant soaked cloth.
o	Bag, label and remove all trash for final disposal.
o	Remove desk blotters and bag for final disposal. 
o	Empty and leave all desk drawers open.
o	Sterilize with paraformaldehyde essential papers and books, if desired.

2.	Room Preparation
o	Cover supply and exhaust duct openings with plastic and tape‑sealed edges in areas where the ventilation system cannot be shut down because it is being shared with another area, or
o	Shut down the system or throttle it back to minimum flow through the system in areas where the ventilation system is not shared with another area
o	Label (room number, location, etc.) and place biological indicators (spore strips containing spores of Bacillus subtilis) through out the area being fumigated.
o	Maintain relative humidity at 60%; add water to the fry pans designated for water if it falls below 60%.  
o	Maintain room temperature at 25 °C. 
o	Pour 1 gallon of liquid disinfectant with proven efficacy against B. anthracis or a solution of one part 5% sodium hypochlorite (household bleach) and nine parts water into each floor or sink drain in affected area.
o	Post warning signs indicating a formaldehyde hazard on the outside of the doors to the clean change room. 

3.	Preparation of the Paraformaldehyde and Disinfection

3.1	Weigh out paraformaldehyde. Calculate the amount of paraformaldehyde required as follows: 
Multiply the volume of area to be cleaned in feet cubed (ft3) by 0.3 grams (g)/ft3 and divide the answer by the percentage of formaldehyde in the paraformaldehyde to be used for the cleanup.
Example: An area with the measurements 10 ft (length) by 15 ft (wide) by 12 ft (height) has a volume of 1,800 ft3. The paraformaldehyde used contains 91% formaldehyde. The amount of paraformaldehyde needed is (1,800 ft3 x 0.3 g/ft3) divided by (0.91) = 594 g.   

3.2	Weigh out ammonium bicarbonate. Calculate the amount of ammonium bicarbonate required as follows:         
		Multiply the grams of paraformaldehyde determined in Step 3.2 by 1.1.             
Example: In the example in Step 3.1, 594 g of paraformaldehyde is needed. The amount of ammonium bicarbonate needed
is  (594 g) x (1.1) = 653 g.   

3.3	Plug electric fry pans into interval timers, and place them in the areas to be cleaned. Turn them to their maximum temperature (420° F), and check that they operate correctly.

3.4	 Put on a full‑face respirator equipped with an industrial canister approved by the National Institute for Occupational Safety and Health (NIOSH)/Mine Safety and Health Administrations (MSHA) for use with formaldehyde. 

3.5	Place pre‑weighed ammonium bicarbonate into electric fry pans designated for ammonium bicarbonate and pre-weighed paraformaldehyde into electric fry pans designated for paraformaldehyde. Do not place more than 908 g ammonium bicarbonate or paraformaldehyde in any one fry pan.

3.6	Set the time fry pans containing paraformaldehyde and water are to turn on.

3.7	 Set the timers of the fry pans containing paraformaldehyde and water to turn off 2 hours after the start time (production time). The contact time for the formaldehyde gas is 10 hours.

3.8	Set the timer of the fry pans containing ammonium bicarbonate to turn on 12 hours after the start of the fumigation (10 hours after the formaldehyde frying pans have turned off); set the timers to turn off the fry pans 1 hour later.  The production time and contact times for ammonium bicarbonate is 1 hour each. 
4.	Re-entry into Disinfected Area

4.1 Enter the disinfected area only under the following conditions:
•	Two hours after the fry pan containing ammonium bicarbonate was set to turn on (or one hour after it shut off)
•	Only personnel wearing Level A protection (a vapor protective suit constructed of materials resistant to formaldehyde breakthrough for more than 8 hours plus a self-contained breathing apparatus) with emergency rescue personnel equipped with the same PPE standing by. 

4.2	 Take formaldehyde readings using a direct reading meter from several locations.

If the formaldehyde level is below 0.5 ppm, equipment used during the disinfection process may be removed without respiratory protection. If readings are above 0.5 ppm, respirator protection must be worn inside the disinfected area until after the area is washed down and formaldehyde levels are below 0.5 ppm. Enter the disinfected area only while wearing a NIOSH-approved, full-face respirator equipped with canisters specifically approved for protection against formaldehyde vapor in combination with a particulate filter.

4.3	 Collect spore strips from the area cleaned in addition to post cleanup environmental sampling for B. anthracis.  Spore strips in addition to a positive control should be incubated for a 72 hr period and read at 24, 48 and 72 hrs.  If the results of the spore strips are positive in other than the positive control then cleanup must be repeated.  If spore strips are NEGATIVE in combination with post cleanup environmental sampling the area can be considered biologically cleaned.

4.4	Wash down the disinfected area to remove formaldehyde residue. PPE worn during wash down should be a NIOSH-approved, full-face respirator equipped with canisters specifically approved for protection against formaldehyde vapor in combination with a particulate filter, long-sleeve shirt, long pants, protective gloves, rubber boots and rubber apron. 

4.5	Continue air monitoring during the wash down process for the area with a direct reading meter. Respiratory protection equipment as described in paragraph 4.4  must be worn until formaldehyde levels fall below 0.5 ppm.

4.6	 Once the ambient formaldehyde levels fall below 0.5 ppm, and if supply and exhaust ducts have been sealed, they can be uncovered.  If the ventilation system had been shut down or throttled back, notify the facility manager to adjust ventilation system to normal operating conditions

4.7	 Collect electric fry pans, timers, and other equipment used in the cleanup.

4.8	Monitor the formaldehyde level until it is at levels in compliance with state and federal exposure standards.

Table 1
Production and Contact Time for Fumigation with Formaldehyde
Fumigant	Production Time	Contact time	Time to Rentry	
Formaldehyde	2 hours	10 hours	13 hours after beginning of production time for formaldehyde	
Ammonium
Bicarbonate	1 hour	1 hour	See above