COVID-19 Deep Cleaning Safe Work Method Statement

The Therapeutic Goods Administration maintains updated list of disinfectants demonstrated effective against SARS-CoV-2 available on TGA website. Commonly approved products include sodium hypochlorite (household bleach) at 1000ppm concentration (1:50 dilution), quaternary ammonium compounds at specified concentrations, hydrogen peroxide solutions typically 3-7%, and alcohol-based products at 70% concentration. Contact time requirements vary by product and concentration: sodium hypochlorite typically requires 1 minute contact time for virucidal activity, quaternary ammonium compounds often specify 5-10 minutes, hydrogen peroxide varies 1-10 minutes depending on concentration, and 70% alcohol requires 30 seconds. Critical principle is that surfaces must remain visibly wet throughout entire specified contact time; premature drying or immediate wiping eliminates effectiveness regardless of product strength. If surface dries before contact time completion, re-apply disinfectant to maintain wetness. Always follow manufacturer instructions on product label as formulations and required contact times vary between products even within same chemical class. Some products marketed as 'disinfectants' lack demonstrated virucidal activity; verify product appears on TGA list rather than assuming all cleaning products are effective against COVID-19. For food contact surfaces, rinse with potable water after disinfectant contact time completion to remove chemical residues before food preparation. Selection between product types depends on surface compatibility: bleach may damage certain metals and colored fabrics, quaternary ammonium compounds leave residual film on some surfaces, alcohol evaporates rapidly making contact time challenging to maintain on large surfaces, and hydrogen peroxide can bleach certain materials. Choose products appropriate for specific surfaces being treated whilst ensuring virucidal efficacy is demonstrated.

P2/N95 respirators providing minimum 95% filtration efficiency are strongly recommended for COVID-19 cleaning work as they filter both droplets and smaller aerosol particles that may remain suspended in air. Surgical masks primarily protect against large droplets and provide limited filtration of smaller aerosols. During cleaning activities, workers spend extended periods in spaces where confirmed COVID-19 cases recently spent time, potentially encountering higher virus concentrations than brief public encounters. Respirators must be fit-tested to individual workers annually to verify proper seal; without fit-testing, facial dimensions may prevent effective seal allowing unfiltered air leakage around mask edges. Fit-testing involves quantitative or qualitative testing using specialized equipment operated by trained personnel. Workers must be clean-shaven in respirator seal area as even short stubble prevents proper seal and invalidates respiratory protection. Before each use, conduct positive and negative pressure seal checks: positive check by exhaling sharply with hands cupping respirator and feeling for air leakage at edges, negative check by inhaling sharply and verifying respirator collapses against face with no air leaking in. If seal check fails, readjust respirator or try different size/model. For extended cleaning operations exceeding 4 hours, powered air-purifying respirators (PAPRs) reduce breathing resistance and worker fatigue compared to filtering facepiece respirators. Surgical masks may be considered acceptable only for very brief cleaning activities in well-ventilated spaces following extensive aerosol clearance periods, but respirators provide superior protection and are recommended whenever feasible. Respirator requirements are separate from public mask mandates; occupational respiratory protection has different regulatory framework under WHS regulations than public health mask orders for community settings.

Safe reoccupation timing depends on several factors including ventilation adequacy, disinfectant type used, and whether enhanced ventilation continues post-cleaning. With adequate ventilation (windows open or mechanical systems at maximum capacity), buildings can typically be reoccupied immediately after cleaning completion as disinfection eliminates viable virus from surfaces and enhanced ventilation clears any aerosolized particles disturbed during cleaning. If strong chemical odors persist indicating inadequate off-gassing, suggest delaying reoccupation or maintaining enhanced ventilation until odors dissipate. Some disinfectants including chlorine bleach produce irritating vapors requiring extended ventilation. Hydrogen peroxide products generally have minimal residual odors. For buildings without adequate ventilation capability, recommend minimum 2-hour waiting period after cleaning completion before reoccupation allowing settlement and dilution of any disturbed particles and chemical off-gassing. This waiting period allows approximately 3-6 air changes in typical spaces with modest ventilation, sufficient for 99% reduction in airborne particle concentration. For healthcare and aged care facilities housing vulnerable populations, some infection control experts recommend longer waiting periods or enhanced verification procedures. No specific regulatory timeframe is mandated; determinations balance infection risk against operational needs for rapid facility return. Documented cleaning completion including areas treated, products used, and ventilation implemented provides evidence supporting reoccupation decisions. Communicate reoccupation timing recommendations clearly to facility management allowing informed decisions balancing safety with operational requirements. Continue enhanced ventilation during initial reoccupation period if feasible providing additional safety margin. Brief returning occupants on cleaning activities conducted and ongoing precautions including hand hygiene, physical distancing, and symptom monitoring that remain important regardless of environmental decontamination completion.

Waste classification requirements for COVID-19 cleaning materials vary between Australian jurisdictions and have evolved throughout pandemic as understanding of transmission risks developed. Initially, many jurisdictions classified all COVID-19 contaminated materials as clinical waste requiring disposal through licensed clinical waste contractors with incineration or specialized treatment. Current guidance in most jurisdictions allows disposal of COVID-19 cleaning waste (used PPE, cleaning cloths, etc.) through general waste streams provided waste is double-bagged, sealed, and labelled. This reflects understanding that COVID-19 transmission through waste handling is low risk particularly for waste that has undergone disinfection through contact with virucidal cleaning chemicals. However, specific requirements differ: healthcare facilities generally maintain stricter clinical waste classification for all infectious materials including COVID-19 waste. Aged care facilities may have jurisdiction-specific requirements. Community cleaning of non-healthcare settings typically follows less stringent general waste disposal. Confirm current requirements with local health department or environmental protection authority as guidance may change based on epidemiological conditions. If any doubt exists about classification, default to clinical waste disposal providing greater safety margin. Clinical waste disposal involves: placing waste in yellow clinical waste bags marked with biohazard symbols, sealing when 2/3 full, labelling with contents and date, storing securely until collection by licensed contractor, maintaining documentation of waste transfer including consignment notes. General waste disposal requires: double-bagging in heavy-duty plastic bags, secure sealing, notation on bags warning of potentially infectious contents (though not requiring biohazard symbols), storage preventing public or animal access before collection, disposal through regular commercial waste collection. Never place sharps (needles, blades) in general waste regardless of COVID-19 context; all sharps require puncture-resistant container disposal through clinical waste pathways.

If COVID-19 symptoms develop following cleaning work (fever, cough, sore throat, shortness of breath, fatigue, body aches, loss of taste/smell, or any respiratory symptoms), immediately isolate from others, notify supervisor, and undergo COVID-19 testing according to current health authority protocols. Early symptom recognition and prompt testing enables early treatment if positive and prevents transmission to colleagues, household members, and subsequent cleaning sites. Describe exposure circumstances to testing provider including recent COVID-19 cleaning work allowing appropriate clinical assessment. If test is positive confirming COVID-19 infection, follow health authority isolation requirements (typically minimum 7 days from symptom onset and until fever-free for 24 hours without medication). Supervisor should conduct contact tracing identifying colleagues who worked alongside infected cleaner, notifying them of potential exposure and monitoring for symptoms. Assess whether infection was occupationally acquired: consider whether PPE was worn correctly throughout work, whether any PPE failures or unprotected exposures occurred, and whether community exposures unrelated to work may have caused infection. Workers compensation may apply for occupationally acquired COVID-19 depending on jurisdiction and evidence of work-relatedness. Document exposure circumstances, symptoms, test results, and clinical course for workers compensation claims if applicable. Employers should support infected workers with sick leave, avoid stigmatization, and assess controls to prevent similar exposures to other workers. If multiple workers cleaning same site develop COVID-19, investigate whether common source exposure occurred suggesting inadequate PPE or protocol failures requiring corrective action. Review entire cleaning operation identifying any procedure deviations or control failures that may have contributed to infection. Implement any identified improvements before subsequent cleaning jobs. For workers with confirmed occupational COVID-19, provide access to occupational rehabilitation services if long-term health effects including 'Long COVID' symptoms develop affecting work capacity. Brief all cleaning personnel that while proper PPE and protocols greatly reduce infection risk, no control measure is 100% effective and symptom monitoring with prompt testing remains important. Create workplace culture where workers feel safe reporting symptoms without fear of penalties, as delayed reporting increases transmission risk to colleagues.

COVID-19 deep cleaning requirements for construction sites depend on several factors including nature of case's work activities, areas accessed, duration spent on site, proximity to other workers, and time elapsed since case was infectious on site. Not all positive cases trigger deep cleaning requirements; assess case-by-case considering transmission risk. Deep cleaning is strongly recommended when: confirmed case spent significant time (several hours or full shifts) in shared enclosed spaces including site offices, crib rooms, amenities, or enclosed work areas; case had close prolonged contact with multiple workers in confined spaces; case used shared facilities including toilets, break rooms, or amenities during infectious period; case worked in areas that will be promptly accessed by other workers without natural ventilation opportunities. Deep cleaning may not be necessary when: case worked primarily outdoors in well-ventilated spaces with minimal enclosed area contact; case had minimal contact with shared facilities spending most time in personal work zone; several days have elapsed since case was infectious on site allowing natural viral decay; case's duties involved minimal contact with surfaces subsequently accessed by others. SARS-CoV-2 viability on surfaces decays over time: on plastic and stainless steel up to 72 hours, on cardboard approximately 24 hours, on copper surfaces about 4 hours. If significant time has elapsed since case's last site attendance (>72 hours), viral decay combined with routine cleaning may be sufficient without specialized deep cleaning. For outdoor construction work in well-ventilated open air environments, surface transmission risk is very low and deep cleaning may be unnecessary. For enclosed or partially enclosed work areas, amenities, or site offices, deep cleaning following positive cases demonstrates due diligence and protects other workers. Consult current health authority guidance as recommendations evolved throughout pandemic and continue changing with epidemiological conditions. Some jurisdictions mandated deep cleaning following any confirmed case on premises; others use risk-based approach assessing necessity case-by-case. Document decision-making rationale whether deep cleaning is conducted or deemed unnecessary, providing evidence of systematic risk assessment. Communication with workers is critical: explain either why deep cleaning is occurring or why it's deemed unnecessary based on specific circumstances, preventing anxiety from perceived inadequate response. Routine enhanced cleaning of high-touch surfaces and amenities should continue regardless of confirmed cases as baseline control measure throughout construction projects during pandemic or endemic phases.