Measurements on Individuals

The methods listed above to evaluate the thermal environment assume an average person. As individuals can react very differently, both regarding acceptance of a given environment and regarding the strain that a given en­vironment imposes, it may under certain circumstances be beneficial to in­corporate individual physiological and subjective measurements. Also, there may be a need for evaluation of an individual’s capability for per­forming a certain job under severe conditions in the field or in an ergo­nomics laboratory investigation.

6.3.7.1Physiological Measurements

ISO EN 9886 presents the principles, methods, and interpretation of measurements of relevant human physiological responses to hot, moder­ate, and cold environments. The standard can be used independently or to complement other standards. Four physiological measures are consid­ered: body core temperature, skin temperature, heart rate, and body mass loss. Comments are also provided on the technical requirements, relevance, convenience, annoyance to the subject, and cost of each of the physiological measurements. The use of ISO 9886 is mainly for extreme cases, where individuals are exposed to severe environments, or in labo­ratory investigations into the influence of the thermal environment on humans.

6.3.7.2Subjective Measurements

Subject scales are useful in the measurement of subjective responses of persons exposed to thermal environments. They are particularly useful in moderate environments and can be used independently or to complement the use of the objective methods (e. g., thermal indices) that were described previously. ISO EN 10551 presents the principles and methodology behind the construction and use of subjective scales and provides examples of scales that can be used to assess thermal environments.

The medical screening standard, ISO DIS 12894, provides advice to those concerned with the safety of human exposures to hot or cold thermal environments, about health screening and surveillance that may be appro­priate prior to and during such exposures. This guidance is applicable to both occupational and laboratory exposures to extreme environments. In either case an assessment should be made of the expected thermal stress on the individual, but the detailed arrangements for medical supervision may differ between the two situations. Control of occupational exposures must also satisfy national health and safety legislation. The laboratory or cli­matic chamber studies for which this standard is relevant include those in which people may be exposed to high or low ambient conditions or local heating or cooling.

Class C (comfort) Class S (thermal stress)

Measuring

Range

Accuracy

Measuring

Range Accuracy

 

Response time (90%)

 

Measurements on Individuals

Response time {90%)

 

Quantity Symbol

 

The shortest possi­ble. Value lo be specified as characteristic of the measur­ing instrument

The shortest possi­ble. Value to be specified as char­acteristic of t he measuring instrument

— *H; to + 120’C

The shortest possi­ble. Value to be specified as char­acteristic of the measuring instrument

The shorresr possi ble. Value to be specified as characteristic of the measur­ing instrument

-40 °Cto + 150 °C

50)J °C

— 50)l ‘:’C

I’he shortest — possi­ble. Value to be specified as characteristic of the measur­ing instrument.

1 tie shortest possi­ble. Value to be specified as char­acteristic of the measuring instrument

10 to 40 Required: ±2 °C

°C Desirable: ±0.2 °C

These levels are difficult or even impossible to achieve in certain cases with the equip­ment normally avail­able. When they cannot be achieved, indicate the actual measuring precision

0 co 50 °C Required: ±0.5 *C Desirable: ±0.2 °C These levels shall be guaranteed at least lor a deviation

< 10°C

Required: ±0.5 9C Desirable: ±0.2 °C These levels shall be guaranteed at least tor a deviation | ty — Jj equal to 10 °C

Required:

-40 to 0 °C: ± (0.5 + 0.01 jf. j) °C > 0 to 50 °C: ± 0.5 °C > 50 to 120aC:±[0.5 + 0.04(fi-50)] 3C Desirable — retlu^ret^ accuracy

These levels shall be guaranteed

At least for a deviation t, — equal to 20 °C

Required:

-40 to 0 °C:± (5 + 0.02. tX^C

> 0 to 50 °C: ± 5°C

> 50 to 120 °C: ±15 + 0.08(^-50)] °C Desirable:

— 40 to 0 "C: ± (0.5 + 0.01 jt, ) ‘•’C

> 0 to 50 °C: ±0.5°C

> 50 to 120 °C: ± [0.5 + 0.04(r

Required:

— 60 to 0 °C: ± ( 1 + 0.01 > 0 to 50 °C: ± I °C > 50 to 200°C: ± f 1 f0.04(fr< Dcsinb!’ re(^u’re^ ‘1l-‘cur-1cy

The air temperature sensor — shall be effectively pro­tected from any effects of thermal radiation coming from hot or cold walls.

An indication of the mean value over a period of 1 min is also desirable.

When the measurement is carried out with a black sphere, rhe inaccuracy relation to the mean radiant rernperature can be ay high as ±5 °C for class C and ± 20 °C for class S according to the environment and the inaccuracy for f,, t, and V

Air tempera­ture

 

Measurements on Individuals

Mean radiant teinpera —

 

Plane radiant tempera­ture

 

393

подпись: 393These levels shall be guaranteed at least lor a deviation jr.,, — i

Class C (comfort)

Quantity Symbol

Measuring

Range

Accuracy

Response time (W%)

Ліг velocity V.,

0,05 ro 1 m/s

Required:

±(0.05 + 0.05^} m/ s

Desirable:

±(0.02 + 0.07^) ml s

These levels shall be guaranteed whatever the direc­tion of flow within a solid angle o) = 3ttst

Required: 0.5

Desirable: 0.2 s

Absolute p.( humidity expressed as partial pressure of water vapor

0.5 ro 1.0 kl’a

±0.15 kPa This level shall be guaranteed even for ait and wall temper­atures equal to or greater chan 30 °C and for a difference

Of at least 10 °C.

The shortest pos­sible. Value to be specified as characteristic of the measur­ing instru­ment

Surface tern — t< perature

0-50 °С

Required: ±1 °C Desirable: ±0.5 °C

The shortest pos­sible. Value to he specified as characteristic of the measur­ing instru­ment

394

подпись: 394

Measuring range Accuracy

 

Response time (90%)

 

Comments

 

The shortest pos­sible. Value to be specified as characteristic of the measur­ing instru­ment.

подпись: the shortest pos-sible. value to be specified as characteristic of the measuring instrument.

Required:

±(0.1 + 0.05 vj rn/s Desirable:

±(0.05 + 0.05 v(J) m/s These levels shall he guaranteed whatever the direction of flow within.1 solid angle (Ј>” jirsr

F. xcept in the case of a unidirectional air current, rhe air velocity sen­sor shall measure the velocity what­ever the direc­tion of the air.

An indication of the mean value and standard devia­tion For a period of 3 min is also desirable.

Lie shortest pos­sible. Value ro be specified as characteristic of rhe measur­ing instru­ment.

подпись: lie shortest pos-sible. value ro be specified as characteristic of rhe measuring instrument.±0.15 kPa

B,0

KP

подпись: b,0
kp
‘fins level shall be guaranteed evm For air and wall temperatures equal to or greater than 30 °C and for a difference

Of at least 20 °C.

The shortest pos­sible. Value to be specified as characteristic of the. measur­ing instru­ment.

подпись: the shortest pos-sible. value to be specified as characteristic of the. measuring instrument.40 ro Required:

+ 120 < 10° C:

9C

±F I + 0.0.5 I0)TC

-10 to 50 °C: ±1JC

> 50 ЫC: ±|1 *0.U5(/,-5O)rC

— , . required accuracy Desirable: —1 ; L

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