General Profile
Cleaning consists of dusting, washing and polishing surfaces; washing walls; mopping, sweeping and polishing floors; as well as disposing of waste and waste water. It is done in offices, public and commercial buildings, homes and factories. It may be done in confined spaces with little ventilation and in spaces not designed with cleaning in mind. Cleaners may be independent or be employed by the enterprise which owns the facilities being cleaned, or they may work for private contractors. Those who clean may be called cleaners, housekeepers, chars, custodians or janitors, depending on the spaces cleaned and the details of the assigned tasks. For example, janitors and custodians may combine cleaning with maintenance and repair work.
Cleaners have usually worked relatively autonomously, compared to other employment categories of similar prestige. Inspection is done by supervisors, although the users of the cleaned spaces also comment on the cleaners’ work. Workers tend to order the tasks themselves and develop their own procedures (Messing, Haëntjens and Doniol-Shaw 1993). However, in commercial spaces in North America, cleaners’ routes have increasingly been determined using software programmed to take account of furniture, floor surfaces and crowding. The desired frequency of operations, area to be cleaned and time estimated for the type of area are used to calculate the total time required. Inspection may be done using a computer-programmed spot check procedure. Some of these procedures may severely underestimate the task as performed in shared space, especially if the inventory is not brought regularly up to date (Messing, Chatigny and Courville 1996).
In Canada, cleaning is the eighth most common profession of men and the tenth most common profession of women; women make up 46% of the profession (Armstrong and Armstrong 1994). In France in 1991, 229,000 cleaners worked for 9,000 cleaning companies; about a third were immigrants and 64% were women (Bretin 1994). In Denmark 85% of the 130,000 cleaners are women (Nielsen 1995). In some countries, tasks in factories and services have often been divided into “light” and “heavy”, assigned formally or informally to female and male workers respectively, who may be paid at different rates (Government of Quebec 1994). Women may dust and polish surfaces, clean bathrooms and empty wastebaskets while men sweep, mop and polish floors and carry waste to incinerators (Messing, Haëntjens and Doniol-Shaw 1993; Messing, Doniol-Shaw and Haëntjens 1993; Messing, Chatigny and Courville 1996). In other countries, men and women can be assigned to all cleaning tasks (Nielsen 1995; Hagner and Hagberg 1989). Cleaners are often relatively old compared to other workers (Bretin et al. 1992; Messing 1991; Nielsen 1995).
Risk Factors and Prevention Strategies
Cleaning may be done with hand-held tools such as brushes, brooms, rags and mops, or may be aided by machines. A variety of chemicals are used to dissolve dirt and to make surfaces appear clean and shiny. The difficulty of the task varies according to the type of surface (rough, smooth, pitted), the height and geometry of the objects cleaned, the degree of crowding of spaces and the vocations exercised in the spaces cleaned. In some places, the need for cleaning may be reduced or eliminated by design changes in the object cleaned (such as self-flushing toilets).
Musculoskeletal load
Cleaning, particularly cleaning furniture and bathrooms and emptying wastebaskets, involves rapid postural changes and many awkward and constrained postures (see table 1). Many objects must be cleaned, at a variety of heights; a typical sequence observed for dusting in a hospital room was: table (81 cm), television (196 cm), table (81 cm), telephone (81 cm), lamp (extends to 188 cm), table foot (11 cm), chair (46 cm), screen (81 cm), armchair (46 cm), window ledge (89 cm), wall sphygmomanometer (154 cm), chair legs (floor to 46 cm), oxygen fixture (137 cm) (Messing, Chatigny and Courville 1995).
Table 1. Postures observed during dusting in a hospital.
Activity |
Duration |
Extension (%) |
Neutral (%) |
Bending <45º (%) |
Bending ≥45º (%) |
Not observable |
Clean nurse station |
3 m, 26 s |
— |
13.6 |
86.4 |
— |
— |
Waste-basket (3) |
1 m, 26 s |
— |
19.8 |
71.1 |
9.2 |
— |
Bath (2) |
5 m, 17 s |
2.8 |
26.6 |
63.1 |
7.5 |
— |
Bathroom corridor (2) |
3 m, 53 s |
6.6 |
18.6 |
71.0 |
3.8 |
0.3 |
Clean rooms |
8 m, 45 s |
3.7 |
29.8 |
60.1 |
2.9 |
3.5 |
Reception area |
3 m, 13 s |
— |
24.7 |
74.4 |
— |
0.9 |
Secretaries’ office |
10 m, 20 s |
3.6 |
32.0 |
59.7 |
0.3 |
4.4 |
Overall |
36 m, 20 s |
3.0 |
26.4 |
65.8 |
2.7 |
2.2 |
Source: Messing, Chatigny and Courville 1995.
Floor cleaning requires repeated movements (fundamental cycle time of 1 to 2 seconds in the Sogaard, Fallentin and Nielsen (1996) study) and a sustained moderate bending of the back. Constant pressure is exerted by the hands to push vacuum cleaners or buffers, tasks requiring forces near 10 kg (Messing, Chatigny and Courville 1996). Sogaard, Fallentin and Nielsen (1996) found mean back bending during floor mopping to be 28º and mean neck bending to be 51º. Hagner and Hagberg (1989) also noted static muscular loads especially at the shoulder joint. Nordin et al. (1986) found extensive forward trunk bending in a simulated janitorial task involving floor mopping. Cleaning floors and objects is usually done with repeated movements. Sogaard (1994) suggests that the sustained repetitive motions with infrequent pauses in activity may exhaust the relatively small numbers of muscle fibres involved and result in muscular disorders.
In order to clean, many objects must be moved. During 66 minutes cleaning and polishing floors, 0.7 objects had to be moved per minute, with weights up to 10 kg; during 23 minutes of dusting, 3.7 objects were moved per minute, with weights up to 2 kg (Messing, Chatigny and Courville 1995).
Winkel et al. (1983) and Hagner and Hagberg (1989) note that increasing specialization and standardization have reduced the number of opportunities to vary body movements and postures during cleaning work. It is therefore important to provide adequate break time. Formal or informal division of tasks according to sex may increase the likelihood of musculoskeletal problems by decreasing the variation in movements (Messing, Haëntjens and Doniol-Shaw 1993).
Cardiovascular load
The cardiovascular load can be quite heavy. Johansson and Ljunggren (1989) recorded the heart rate of female cleaners during office or toilet cleaning at 123 beats/minute, 65% of the maximum for their average age of 29.8 years (corresponding to about 35% of their estimated maximal oxygen uptake or VO2 max, close to that of construction workers). Swabbing or mopping resulted in similar heart rates of 122 to 127 beats/minute. Hagner and Hagberg (1989) found a high level of oxygen consumption (up to 40% of the VO2 max) among cleaners doing floor mopping under experimental conditions. Sogaard (1994) found that relative cardiovascular strain of female school cleaners measured in the workplace was 53% of the VO2 max.
To prevent musculoskeletal problems and decrease the cardiovascular load, workload should be appropriate and sufficient rest time should be allowed. Attention should be paid to ease of cleaning when spaces and procedures are being designed and when furnishings are purchased. Vacuuming requires less force if carpets are carefully laid so as not to wrinkle when the vacuum cleaner is passed. The use of adequate tools is important. For example, extendable brushes for dusting can reduce the necessity to reach or climb. Prolonged bending can be minimized if efficient chemicals and tools make it possible to clean quickly, and if cleaning is frequent enough so that dirt does not become hardened.
The common practice of reducing the rate of ventilation in buildings during the evening or night hours, when cleaning is done, reduces air quality for cleaning workers who work during these times and should be avoided. To prevent overwork in the case where cleaning is planned using purchased software, careful observation and verification should be done in order to make sure that times allotted are realistic and take into account multiple use of spaces cleaned. Inventories of rooms and objects cleaned should be updated frequently.
Procedures and apparatus for emptying wastebaskets into bins, and bins into incinerators, have been developed so that manual lifting can be avoided.
Chemicals
Chemicals can be classed as soaps, detergents, disinfectants, porcelain cleaners, scouring powders, wax removers and strippers, solvents, pesticides and drain cleaners. They may contain other ingredients such as fragrances and colouring agents. There may be surface skin contact or they may be inhaled or absorbed through the skin into the system. Damage to the skin, eyes, throat or lungs can result. The risk of exposure depends on the concentration of the chemical and how it is used. Sprays volatilize chemicals and increase exposure. Some chemicals are irritants at low concentration and corrosive at high concentration (acids, oxidizing agents or bases). Others are effective solvents or detergents which may damage the skin barrier and make it more vulnerable to other chemical agents. Still others contain metals (nickel, cobalt, chrome) or other substances which can act as allergens.
Cleaning agents are often sold at high concentrations and diluted on site for use. The common practice of using chemicals at a higher concentration than recommended, in the hope of cleaning more quickly or more efficiently, is a source of overexposure and should be remedied by proper education and by adjusting the workload. Mixing different chemicals can cause accidental intoxication or burns. Work with strong chemicals in poorly ventilated spaces can be a hazard for cleaners and should be avoided.
The Danish Product Register Data Base PROBAS contains information on 2,567 washing and cleaning agents. Of these, 70 are considered to be potentially harmful agents causing chronic or acute health damage, such as corrosives, carcinogens, reproductive toxicants, allergens and neurotoxic agents (Borglum and Hansen 1994). These agents are presented in table 2. A study of the PROBAS register found 33 contact allergens in cleaning agents (Flyvholm 1993).
Table 2. Dangerous chemicals used in cleaning.†
Chemical |
Health damage codes |
Other hazards |
Solvents |
||
Butylglycol |
N* |
|
Isopropyl benzene |
N |
|
Naphtha, white spirit, Stoddard solvent |
N,R |
|
Toluene |
N,R |
Flammable |
Ethanol |
R |
Flammable |
2-Ethoxyethanol |
N,R |
|
2-Methoxyethanol |
R |
|
1-Methyl-2-pyrrolido |
R |
|
Base oil, crude oil |
N |
|
Tetrachloroethylene |
N,R |
|
1,1,1-Trichloroethane |
N |
|
Xylene |
N,R* |
Flammable |
Butyldiglycol |
I |
|
Acids and bases |
||
Acetic acid |
C |
|
Ammonium hydroxide |
I |
Reacts with chlorine bleaches to liberate toxic gas |
Potassium hydroxide |
C |
|
Sodium carbonate |
I |
|
Sodium hydroxide |
C |
|
Phosphoric acid |
C |
|
Sulphuric acid |
C |
|
Residual monomers and impurities |
||
Formaldehyde |
A,K* |
|
Phenol |
N* |
|
Benzene |
K,R,N |
|
Acrylonitrile |
A,K |
|
Butylacrylate |
A |
|
Methylmethacrylate |
A,R |
|
Styrene |
R |
Flammable |
1-Propanol |
N |
Flammable |
Ethyl acrylate |
A,K* |
|
1,2-Ethylene diamine |
A |
|
Ethylene oxide |
A,K,R |
Flammable |
Propylene oxide |
K |
Flammable |
2-Methylaniline |
K |
|
2-Propyn-1-ol |
N |
|
Chelators |
||
Sodium EDTA (ethylene diamine tetraacetic acid) |
R |
|
Sodium NTA (nitrilotriacetic acid) |
K |
|
Anti-rusts |
||
2-Aminoethanol |
N |
|
Triethanolamine |
A |
|
Hexamethylene tetramine |
A |
|
2-Butyn-1,4-diol |
C,T |
|
Disodium metasilicate |
C,I |
|
2-(3H)-Benzothiazolethione |
A |
|
Disinfectants |
||
Borax |
R |
|
Disodium tetraborate |
R |
|
Morpholine |
N |
|
Benzalkonium chloride |
C |
|
Sodium dichloroisocyanurate |
I |
Reacts with acid to liberate toxic gas |
Sodium hypochlorite |
C |
Reacts with acid or ammonia to release toxic gases |
Preserving agents |
||
1,2-Bensisothiazol-3(2H)-one |
A |
|
5-Chlor-2-methyl-3-isothiazolone |
A |
|
2-Methyl-3-isothiazolone |
A |
|
2-Chloracetamide |
A |
|
p-Chlor-m-cresol |
A |
|
Hexahydro-1,3,5-tris- (2-hydroxyethyl)1,3,5-triazine |
A |
|
1,5-Pentadiol |
A |
|
2-Bromo-2-nitro-1,3-propanediol |
T |
|
Fillers |
||
Quartz |
K |
|
Silicon dioxide |
K |
|
Sodium hydrogen sulphate |
C |
|
Others |
||
Subtilisin (Enzyme) |
A |
|
Sodium saccharine |
K |
|
Ammonium peroxodisulphate (bleaching agent) |
A |
|
A = allergen; C = corrosive; I = irritant; K = carcinogen; N = neurotoxic agent; R = reproductive toxic agent; T = toxic if swallowed; * = danger dependent on concentration.
Determination of toxicity was done by the Danish Institute of Occupational Health. †Note that not all cleaning agents have been tested for all toxic properties, so that this list is not necessarily complete or comprehensive. Source: Summarized from Borglum and Hansen 1994. Cleaners who work in factories or hospitals may be exposed to chemicals (or biohazards) associated with the ongoing activities in the spaces they clean. If cleaners are not integrated into the training programmes and social network of the regular workforce, they may be less aware of these hazards than other workers. For example, one study showed that cleaners were the group most often exposed to harmful chemicals of all categories of hospital workers (Weaver et al. 1993). There is some controversy about the use of gloves for cleaning work. Gloves play an important role in protecting the skin from hazardous agents if they fit correctly and are made of impermeable and resistant materials. But wearing gloves constantly can keep perspiration from evaporating. The resulting damp area is a favourable growth medium for infectious agents. Wearing gloves was associated with skin problems in a large sample of Danish cleaners (Nielsen 1996). It is therefore best to wear gloves the minimum time compatible with protection. The necessity for wearing gloves can often be obviated by using tools with long handles, or by other changes in methods. Wearing cotton gloves under rubber or plastic gloves may reduce humidity and protect against allergies to some glove materials (Foussereau et al. 1982). Some hand creams may contain irritants and should be avoided (Hansen 1983). Several other practices diminish exposure to chemicals. When cleaning solutions are stored or prepared, there should be good ventilation, and procedures should permit preparation without any danger of touching or breathing the chemicals. The temptation to work with undiluted chemicals will diminish if workers have adequate time and implements. Also, cleaners may use undiluted chemicals or chemicals that have allergenic fragrances in order to signal to others that they have done their job. This can be done by other means, such as clear inspection procedures and communication links with other workers and with clients of cleaning services. Useful information on prevention of exposure to chemicals can be found in a handbook published by the City of New York (Michaels, undated). Other health risks Cleaners often work evening or night shifts, so as not to interfere with the other activities being carried out in the same spaces. They may therefore suffer the usual effects of shift work on biorhythms. In addition, they may risk violence if they work alone in isolated areas. Cleaners, particularly those who work outside regular building hours and/or who are not part of the regular personnel, may be ignored and excluded from the social network in their workplaces (Messing in press). They may not be given access to the appropriate facilities for breaks and meals. Aside from the psychological effects of exclusion, cleaners may be deprived of information on hazards routinely given to other workers, despite legal requirements in many jurisdictions to provide this information. Also, despite the importance of surface textures and design for their work, they and their supervisors may not be consulted when relevant purchasing and planning decisions are made. This is especially true if cleaning is contracted out. It is therefore important that a special effort be made to include cleaners in occupational health and safety promotion activities in the workplace. Information on characteristics of chemicals, on work procedures and on safety should be discussed with cleaners and clearly posted in the workplace. Health Effects and Disease Patterns Cleaners as a profession have poorer health than others (Nielsen 1995; ASSTSAS 1993; Sogaard 1994). Comparing cleaners with other workers, an analysis of the Quebec Health Survey found, after controlling for age, that women cleaners had the highest prevalence of chronic back problems and cardiopathies of all categories of women workers and that male cleaners had the highest prevalence of musculoskeletal problems and cardiopathies (Gervais 1993). Pregnant cleaners have an increased likelihood of miscarriage (McDonald et al. 1986), giving birth prematurely (McDonald et al. 1988) or bearing children with low birth weight (McDonald et al. 1987). Some large population-based epidemiological studies have found high cancer rates among cleaners. Rates of some brain tumours among US White men have been found to be especially high for cleaning service workers (Demers, Vaughan and Schommer 1991). Among women, invasive cervical cancer is almost five times more common among cleaners than other women (Savitz, Andrews and Brinton 1995). These results are attributed to chemical exposures, particularly solvents. Musculoskeletal problems are often encountered. In Denmark, Nielsen (1995) found that those who left cleaning had a reduced frequency of musculoskeletal symptoms compared to those who stayed in the profession. Cleaning was one of the five trades reporting the most shoulder/neck pain, tendovaginitis and low back pain (Sogaard, Fallentin and Nielsen 1996). A population-based epidemiological study found female cleaners to be particularly likely to have osteoarthritis of the knee, compared to other Swedish workers (Vingard et al. 1991). Cleaners in Quebec hospitals suffer almost twice as many occupational accidents and illnesses as the average Quebec health care worker: 23.8 compared to 13.9 per 100 full-time equivalent workers per year (ASSTSAS 1993). Most lesions involved the trunk or upper limbs (ASSTSAS 1993). Comparing male with female cleaners, a survey of cleaners in the Paris region in France found that men had more back pain and women had more joint pain (Opatowski et al. 1995). These differences are probably attributable to specificities in the tasks assigned to women and men cleaners (Messing, Haëntjens and Doniol-Shaw 1993; Messing, Doniol-Shaw and Haëntjens 1993; Messing, Chatigny and Courville 1996). Cleaners have a high level of skin problems, including dermatitis and eczema (Gawkrodger, Lloyd and Hunter 1986; Singgih et al. 1986). Point prevalences of skin diseases of 15 to 18%and a duration of employment prevalence of 39%have been found among large samples of hospital cleaners (Hansen 1983; Delaporte et al. 1990). Cleaners who spend more time with wet hands have more skin problems (Nielsen 1996). Cleaners may also be injured or infected by broken glass, needles or other sharp objects while handling waste (ASSTSAS 1993). Recently, occupational health specialists have noted symptoms of stress related to work among hospital cleaners, for which they suggest re-examination of the work process (Toivanen, Helin and Hänninen 1993). Low prestige of the profession may be a cause of distress for cleaners (Messing, in press). Accidents, infection and environmental contamination may be prevented by clear and well-publicized guidelines for disposal of dangerous waste in factories, hospitals, offices and public buildings. Since constraints placed on other workers may prevent them from paying full attention to prevention of hazards for cleaners, consultations between cleaners and other workers should be arranged, in order to decide on the appropriate size and placement of wastebaskets, waste separation and labelling. Cleaners should be included whenever waste disposal practices are being planned or reviewed so that realistic methods can be proposed.