1. Flickering tubes: This condition which may be due to defective conditions or by tube which has reached its working life, creates eyestrain.
2. A. Misadjusted Reflector : A source of glare.
B .Installation with line of Vision : In absence of proper control of brightness intensity cause eyestrain and glare. Un shaded light source particularly when within the line of vision creates glare . in many of the industrial plants filament lamps are not equipped with proper reflectors.
3. Lack of uniformity: Variation in intensity of light may result in accident as eye sight is unable to accommodate quickly enough the change.
4. Showdowns or spotty illumination : Such condition is not suitable to production or safety due to relative brightness and surface reflection involved.
5. Inadequate Amount of light : Low level lighting may become source of accident due to eye strain and fatigue.